CN118337192B - Control circuit, method, equipment and medium based on pulse width modulation signal - Google Patents
Control circuit, method, equipment and medium based on pulse width modulation signal Download PDFInfo
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- CN118337192B CN118337192B CN202410779079.6A CN202410779079A CN118337192B CN 118337192 B CN118337192 B CN 118337192B CN 202410779079 A CN202410779079 A CN 202410779079A CN 118337192 B CN118337192 B CN 118337192B
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K7/00—Modulating pulses with a continuously-variable modulating signal
- H03K7/08—Duration or width modulation ; Duty cycle modulation
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K3/00—Circuits for generating electric pulses; Monostable, bistable or multistable circuits
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- H03K3/017—Adjustment of width or dutycycle of pulses
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Abstract
The invention provides a control circuit based on a pulse width modulation signal, which comprises: the pulse width modulation power circuit comprises a first diode, a filter circuit, a first transistor, a second diode, a sampling resistor and a second transistor which are sequentially connected; the first port and the second port of the differential amplifying circuit are respectively connected to two ends of the sampling resistor; and the third port of the pulse width signal modulation circuit is connected with the gate of the first transistor, the fourth port of the pulse width signal modulation circuit is connected with the sixth port of the differential amplifying circuit, and the fifth port of the pulse width signal modulation circuit is connected with the gate of the second transistor. The current at two ends of the controlled element coil is collected through the sampling resistor and is output to the pulse width signal modulation circuit through the differential amplifying circuit, and then the pulse width signal modulation circuit adjusts the duty ratio of the pulse width modulation signal according to the current, so that unexpected disconnection of the relay caused by current fluctuation is prevented.
Description
Technical Field
The invention relates to the field of electric energy control, in particular to a control circuit, a control method, a control device and a control medium based on pulse width modulation signals.
Background
With the rapid development of new energy industry and energy storage industry, electric vehicles and hybrid electric vehicles are vigorously developed, so that relays are widely applied to high-voltage electric energy control devices of intelligent electric vehicles and energy storage systems. In order to meet the requirements of energy conservation and emission reduction, the conventional direct voltage driven relay in the prior art has the problem of higher energy consumption. In contrast, relays based on pulse width modulation signal (PWM) control consume less power, about 25% of direct voltage drive, and PWM control relays are becoming more and more accepted.
In the related art, a common PWM driving method at present is that a microcontroller of an ECU outputs a PWM signal with a fixed frequency and a duty ratio, and the magnitude of a driving current is controlled by adjusting the duty ratio. However, this method lacks monitoring of the current and voltage across the relay coil, which may lead to a reduction of the current and an unintended opening of the relay in case of complex electromagnetic environments or voltage fluctuations.
Disclosure of Invention
The present application aims to solve at least one of the technical problems existing in the prior art. Therefore, the application provides a control circuit, a control method, a control device and a control medium based on a pulse width modulation signal, which can prevent current fluctuation caused under the condition of complex electromagnetic environment or voltage fluctuation so as to lead a relay to be disconnected unexpectedly.
In a first aspect, an embodiment of the present application provides a control circuit based on a pulse width modulation signal, including:
The pulse width modulation power circuit comprises a first diode, a filter circuit, a first transistor, a second diode, a sampling resistor and a second transistor which are sequentially connected; the anode of the first diode is connected with the positive electrode of the power supply, and the source electrode of the second transistor is grounded;
the first port and the second port of the differential amplifying circuit are respectively connected to two ends of the sampling resistor;
And the third port of the pulse width signal modulation circuit is connected with the gate of the first transistor, the fourth port of the pulse width signal modulation circuit is connected with the sixth port of the differential amplification circuit, and the fifth port of the pulse width signal modulation circuit is connected with the gate of the second transistor.
In some embodiments, the pulse width signal modulation circuit comprises a micro control chip, a latch circuit, a timing circuit, a pulse width modulation control circuit, and a pulse width modulation synchronization circuit;
The latch circuit is connected with a seventh port of the micro control chip;
the timing circuit is connected with an eighth port of the micro control chip, and the timing circuit is connected with the latch circuit;
The pulse width modulation synchronous circuit is connected with a ninth port of the micro control chip;
the pulse width modulation control circuit is connected with the pulse width modulation synchronous circuit, the timing circuit is connected with the pulse width modulation control circuit, the pulse width modulation control circuit is connected with the grid electrode of the second transistor, and the latch circuit is connected with the grid electrode of the first transistor.
In some embodiments, the pulse width signal modulation circuit further comprises a switching edge adjustment circuit connected to a tenth port of the micro control chip and between the pulse width modulation control circuit and the gate of the second transistor.
In some embodiments, two ends of the second diode are connected to two ends of the controlled electronic component through a twisted pair shielding harness.
In a second aspect, an embodiment of the present application provides a control method based on a pulse width modulation signal, including:
Controlling a pulse width signal modulation circuit to send a closing signal to a first transistor so as to enable the first transistor to be closed;
Controlling the pulse width signal modulation circuit to continuously output a pulse width signal with a preset duty ratio for a first preset time so as to enable the second transistor to be closed, and after the first transistor and the second transistor are closed, electrifying the relay coil to be closed;
Acquiring a coil current value flowing through a sampling resistor, and adjusting the duty ratio of the pulse width signal until the coil current value meets a preset coil current value range;
And controlling the pulse width signal modulation circuit to send an off signal to the first transistor and the second transistor so as to turn off the first transistor and the second transistor.
In some embodiments, the range of coil current values includes a first coil current value and a second coil current value, wherein the first coil current value is greater than the second coil current value, and the adjusting the duty cycle of the pulse width signal according to the coil current value until the coil current value meets a preset range of coil current values includes:
When the coil current value is larger than the preset first coil current value, the duty ratio of the pulse width signal is reduced so that the coil current value is smaller than the first coil current value;
And when the coil current value is smaller than the preset second coil current value, increasing the duty ratio of the pulse width signal so that the coil current value is larger than the second coil current value.
In some embodiments, after said adjusting the duty cycle of the pulse width signal until the coil current value meets a preset coil current range value, further comprising:
The same synchronous pulse width signal is output according to the pulse width signal, and the synchronous pulse width signal is transmitted to a pulse width modulation synchronous circuit of the control circuit;
The pulse width modulation synchronization circuit sends the synchronous pulse width signal to a pulse width modulation control circuit of the control circuit so that the pulse width modulation control circuit keeps outputting the pulse width signal.
In some embodiments, the controlling the pulse width signal modulation circuit to send an off signal to the first transistor and the second transistor to turn off the first transistor and the second transistor includes:
The control micro-control chip sends a reset signal to a timing circuit of the control circuit, and when the timing circuit detects the disconnection signal, timing is started to obtain timing data;
Outputting the disconnection signal to a latch circuit of the control circuit and the pulse width modulation control circuit when the timing data exceeds a first preset time;
the latch circuit receives the disconnection signal and then turns off the output, the first transistor is disconnected, the pulse width modulation control circuit receives the disconnection signal and then turns off the output of the pulse width signal, and the second transistor is disconnected.
In a third aspect, an embodiment of the present application provides an electronic device, including: a memory, a processor, the memory storing a computer program, the processor implementing the pulse width modulation signal based control method according to any one of the embodiments of the second aspect of the present application when executing the computer program.
In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium storing a program that is executed by a processor to implement a control method based on a pulse width modulation signal according to any one of the embodiments of the second aspect of the present application.
The control circuit based on the pulse width modulation signal has at least the following beneficial effects:
According to an embodiment of the application, a control circuit based on a pulse width modulation signal comprises: the pulse width modulation power circuit comprises a first diode, a filter circuit, a first transistor, a second diode, a sampling resistor and a second transistor which are sequentially connected; the anode of the first diode is connected with the positive electrode of the power supply, and the source electrode of the second transistor is grounded; the first port and the second port of the differential amplifying circuit are respectively connected to two ends of the sampling resistor; and the third port of the pulse width signal modulation circuit is connected with the gate of the first transistor, the fourth port of the pulse width signal modulation circuit is connected with the sixth port of the differential amplifying circuit, and the fifth port of the pulse width signal modulation circuit is connected with the gate of the second transistor. The application collects the current at two ends of the controlled element coil through the sampling resistor, and outputs the current to the pulse width signal modulation circuit through the differential amplifying circuit, and then the pulse width signal modulation circuit adjusts the duty ratio of the pulse width modulation signal according to the current, thereby preventing the relay from being disconnected unexpectedly due to current fluctuation caused under the complex electromagnetic environment or voltage fluctuation.
Additional aspects and advantages of the application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the application.
Drawings
The foregoing and/or additional aspects and advantages of the application will become apparent and may be better understood from the following description of embodiments taken in conjunction with the accompanying drawings in which:
fig. 1 is a schematic diagram of a control circuit based on a pwm signal according to an embodiment of the present application;
FIG. 2 is a schematic diagram of another PWM signal-based control circuit according to an embodiment of the present application;
FIG. 3 is a flowchart of an alternative control method based on PWM signals according to an embodiment of the present application;
FIG. 4 is a flowchart of another alternative control method based on PWM signals according to an embodiment of the present application;
FIG. 5 is a flowchart of another alternative control method based on PWM signals according to an embodiment of the present application;
FIG. 6 is a flowchart of another alternative control method based on PWM signals according to an embodiment of the present application;
FIG. 7 is a flowchart of an alternative embodiment of a relay control based on PWM signals according to an embodiment of the present application;
Fig. 8 is a schematic diagram of a hardware structure of an electronic device according to an embodiment of the present application.
Detailed Description
Embodiments of the present application are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative only and are not to be construed as limiting the application.
In the description of the present application, a number means one or more, a number means two or more, and greater than, less than, exceeding, etc. are understood to not include the present number, and above, below, within, etc. are understood to include the present number. If a description is given of a first, the second is only used for distinguishing technical features, and is not to be construed as indicating or implying relative importance or implying the number of technical features indicated or the precedence of the technical features indicated.
In the description of the present application, it should be understood that the direction or positional relationship indicated with respect to the description of the orientation, such as up, down, left, right, front, rear, etc., is based on the direction or positional relationship shown in the drawings, is merely for convenience of describing the present application and simplifying the description, and does not indicate or imply that the apparatus or element to be referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present application.
In the description of the present specification, reference to the terms "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the application. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
In the description of the present application, unless explicitly defined otherwise, terms such as arrangement, installation, connection, etc. should be construed broadly and the specific meaning of the terms in the present application can be determined reasonably by a person skilled in the art in combination with the specific content of the technical solution. In addition, the following description of specific steps does not represent limitations on the order of steps or logic performed, and the order of steps and logic performed between steps should be understood and appreciated with reference to what is described in the embodiments.
With increasing importance of new energy technology and sustainable development strategy in the global scope, the new energy industry and the energy storage industry have come to have an unprecedented rapid development period, especially in the fields of Electric Vehicles (EV) and Hybrid Electric Vehicles (HEV), and at the same time, higher requirements are put forward on the control of high-voltage electric energy, and the relay is used as a key electrical switch component, so that the high-voltage circuit can be rapidly turned on and off under the instruction of an Electronic Control Unit (ECU), and the relay is an important foundation for realizing efficient and safe control of electric energy.
In the face of global energy conservation and emission reduction pressure, the traditional direct voltage driven relay gradually exposes the defect of inadaptation to the modern energy requirement due to the inherent high energy consumption characteristic. In this context, relay technology based on pulse width modulation signal (PWM) control has been developed and rapidly developed. This technology has gained wide acceptance and favor in the industry with its significant low power consumption advantage (power consumption is only about 25% of that of the traditional direct voltage drive approach). The PWM technology realizes accurate control of the driving current of the relay through effective modulation of the voltage signal, so that the energy efficiency is improved, and the performance of the device is optimized.
Among the many PWM control techniques, one of the most common is to generate a PWM signal of a fixed frequency and duty cycle using a microcontroller in an Electronic Control Unit (ECU). The current passing through the relay coil can be finely controlled by finely adjusting the duty ratio of the PWM signal, so that the accurate control of the relay action is realized. The method has the advantages of simplicity and high efficiency, and can meet the requirements of most application scenes. However, this approach also has certain limitations in practical applications. Particularly, under the condition of complex electromagnetic environment or large voltage fluctuation, due to lack of real-time monitoring and adjustment of current and voltage of a relay coil, unexpected current fluctuation can be caused, and then the relay is disconnected at unexpected time, so that the stability and reliability of the whole system are affected.
Based on the control circuit, the control circuit based on the pulse width modulation signal is constructed, the current at two ends of the coil of the controlled element is collected through the sampling resistor and is output to the pulse width signal modulation circuit through the differential amplifying circuit, and then the pulse width signal modulation circuit adjusts the duty ratio of the pulse width modulation signal according to the current, so that the relay is prevented from being disconnected unexpectedly due to current fluctuation caused under the condition of complex electromagnetic environment or voltage fluctuation.
Referring to fig. 1, fig. 1 is a schematic diagram of a control circuit based on a pwm signal according to an embodiment of the present application, and as shown in the drawing, a control circuit 1000 includes:
the pulse width modulation power circuit 1100, the pulse width modulation power circuit 1100 includes a first diode 1110, a filter circuit 1120, a first transistor 1130, a second diode 1140, a sampling resistor 1150, and a second transistor 1160 connected in sequence; wherein, the anode of the first diode 1110 is connected to the positive electrode of the power supply, and the source of the second transistor 1160 is grounded;
the differential amplifying circuit 1200, wherein a first port and a second port of the differential amplifying circuit 1200 are respectively connected to two ends of the sampling resistor 1150;
The third port of the pulse width signal modulation circuit 1300 is connected to the gate of the first transistor 1130, the fourth port of the pulse width signal modulation circuit 1300 is connected to the sixth port of the differential amplifier circuit 1200, and the fifth port of the pulse width signal modulation circuit 1300 is connected to the gate of the second transistor 1160.
The cathode of the first diode 1110 is connected to the input end of the filter circuit 1120, the output end of the filter circuit 1120 is connected to the drain electrode of the first transistor 1130, the source electrode of the first transistor 1130 is connected to the cathode of the second diode 1140, the anode of the second diode 1140 is connected to one end of the sampling resistor 1150, the other end of the sampling resistor 1150 is connected to the drain electrode of the second transistor 1160, and the source electrode of the second transistor 1160 is grounded.
The first diode 1110, which is used as a reverse protection diode, can prevent the unexpected reverse connection of the external power source from causing the unexpected closing operation of the controlled electronic component 2000 (such as a relay). When the polarity of the external power supply is wrong, the first diode 1110 can prevent the current from passing through the circuit, so as to effectively prevent the sensitive components such as the controlled electronic component 2000 from being damaged or abnormally operated. By ensuring that current can only flow in a specific direction, the first diode 1110 ensures the safety of the entire circuit system, avoiding possible circuit failure or damage due to reverse connection of the power supply.
The filter circuit 1120 can filter high-frequency noise and abrupt change in a power supply, keep stability of power supply voltage, prevent sudden power supply voltage fluctuation from affecting the circuit, ensure that the power supply in a signal driving process is stable and pass through a filtering function, the filter circuit 1120 can effectively reduce electromagnetic interference which is conducted out along a power line by pulse width signals (PWM signals), can improve electromagnetic compatibility (EMC) performance of products, reduce interference caused by the circuit to external equipment and systems, and ensure stability and reliability of the system.
The second diode 1140 acts as a freewheeling diode and the second diode 1140 may provide the freewheeling current required by the coils of the controlled electronic element 2000 during the low-level of the pulse width signal. In a relay coil, when the control signal is at a low level, a continuous current may be required within the coil to keep the relay in an operational state or to ensure proper operation. By the freewheel current provided by the second diode 1140, it is ensured that the current in the coil of the controlled electronic element 2000 is not interrupted when the control signal is switched, so that the normal operation of the controlled electronic element 2000 is ensured, and the failure or unstable operation of the controlled electronic element 2000 caused by the current interruption is avoided.
The first transistor 1130 is to cope with the short-circuit failure of the second transistor 1160, and once the second transistor 1160 is shorted, the coil of the controlled electronic element 2000 may be continuously electrified or abnormally operated, and the first transistor 1130 may be interposed and controlled in this case. By controlling the first transistor 1130, the current supply to the controlled electronic component 2000 may be turned off, thereby avoiding unintended operation or continued energization of the controlled electronic component 2000. This helps to protect the controlled electronic component 2000 from short circuit failure.
The sampling resistor 1150 is used for collecting the current at two ends of the coil of the controlled electronic element 2000, the current signal collected by the sampling resistor 1150 is amplified and processed by the differential amplifying circuit 1200, and the signal output by the differential amplifying circuit 1200 enters the pulse width signal modulating circuit 1300, so that an analog-to-digital conversion port (ADC) in the pulse width signal modulating circuit 1300 adjusts the duty ratio of the pulse width signal according to the collected current of the coil of the controlled electronic element 2000. The pulse width signal modulation circuit 1300 adjusts the pulse width signal in real time according to the current condition to ensure the normal operation and stability of the controlled electronic element 2000 and outputs the pulse width signal to the gate of the second transistor 1160, thereby controlling the working state of the second transistor 1160 and further controlling the working state of the coil of the controlled electronic element 2000, and realizing the accurate control of the controlled electronic element 2000. In general, the sampling resistor 1150 helps the system acquire the current information of the coil of the controlled electronic element 2000 in real time, and the differential amplifying circuit 1200 and the pulse width signal modulating circuit 1300 realize the adjustment of the pulse width signal, so as to finally influence the working state of the second transistor 1160 and realize the accurate control of the controlled electronic element 2000.
In some embodiments, the pulse width signal modulation circuit 1300 includes a micro-control chip 1310, a latch circuit 1320, a timing circuit 1330, a pulse width modulation control circuit 1340, and a pulse width modulation synchronization circuit 1350;
wherein the latch circuit 1320 is connected to a seventh port of the micro control chip 1310;
The timing circuit 1330 is connected to the eighth port of the micro control chip 1310, and the timing circuit 1330 is connected to the latch circuit 1320;
the pwm synchronization circuit 1350 is connected to the ninth port of the micro control chip 1310;
the pwm control circuit 1340 is connected to the pwm synchronization circuit 1350, and the timing circuit 1330 is connected to the pwm control circuit 1340, the pwm control circuit 1340 is connected to the gate of the second transistor 1160, and the latch circuit 1320 is connected to the gate of the first transistor 1130.
The seventh port of the micro control chip 1310 is an I/O port, and is connected to the input end of the latch circuit 1320, the eighth port is a reset trigger signal port, and is connected to the input end of the timing circuit 1330, and the input end of the timing circuit 1330 is connected to the input end of the latch circuit 1320, the timing circuit 1330 starts timing after receiving the reset signal of the micro control chip 1310, and after the timer times out, the timing circuit 1330 sends a signal, which disconnects the input signal of the latch circuit 1320, so that the output state of the latch circuit 1320 is changed. The change in the output state of latch circuit 1320 affects the operation of first transistor 1130 and second transistor 1160, ultimately resulting in the controlled electronic device 2000 being turned off, and the latch circuit 1320 is designed to maintain its original state after receiving the signal from timing circuit 1330 until the next valid signal occurs. By such design, the system can effectively avoid unexpected operation of the relay when the micro control chip 1310 is reset, and ensure the stable state of the controlled electronic element 2000. The cooperation of the timing protection mechanism and the latch circuit 1320 can ensure a controllable turn-off operation of the controlled electronic component 2000 when a reset occurs, thereby enhancing the reliability and safety of the circuit.
The pwm synchronization circuit 1350 is configured to transmit the same pwm signal to the pwm control circuit 1340 in real time according to the pwm signal output from the micro control chip 1310 to the second transistor 1160, so as to ensure that the pwm control circuit 1340 tracks the variation of the output from the micro control chip 1310. The pwm control circuit 1340 maintains a pulse width signal output by receiving a pulse width signal, and is responsible for maintaining a specific pulse width signal output state in the circuit. Through the cooperation of the pwm synchronization circuit 1350 and the pwm control circuit 1340, the continuity and stability of the pwm signal in the circuit can be ensured, the accuracy of the pwm signal output can be maintained, and the variation of the micro control chip 1310 can be tracked in real time, so as to meet the requirement of precise control of the pwm signal.
Referring to fig. 2, in some embodiments, the pwm circuit 1300 further includes a switch edge adjustment circuit 1360, the switch edge adjustment circuit 1360 is connected to the tenth port of the micro-control chip 1310 and is connected between the pwm control circuit 1340 and the gate of the second transistor 1160.
The switch edge adjusting circuit 1360 is used to adjust the time of the rising edge and the falling edge of the pulse width signal. By adjusting the edges of the pulse width signals, electromagnetic interference can be reduced, electromagnetic compatibility (EMC performance) can be improved, and stability and anti-interference capability of the system in an electromagnetic environment can be improved.
In some embodiments, two ends of the second diode 1140 are connected to two ends of the controlled electronic component 2000 through a twisted pair shielding harness 1400. The use of twisted pair shielding harness 1400 connection can effectively reduce the reduction in EMC performance of the product caused by the spatial radiation generated by the pulse width signal through the harness.
In some embodiments, the controlled electronic component 2000 may be a relay, and the twisted pair shielding harness 1400 is responsible for transmitting control signals to the relay, so as to control the operation of the relay, and since electromagnetic noise and interference may be generated when the relay is operated, the influence of the interference on the surrounding environment and the system can be reduced by adopting the twisted pair shielding harness.
Referring to fig. 3, a control method based on a pwm signal according to an embodiment of the present invention is applied to the control circuit based on a pwm signal, and may include, but is not limited to, steps 310 to 340 as follows:
step 310, controlling the pulse width signal modulation circuit to send a closing signal to the first transistor so as to close the first transistor;
step 320, controlling the pulse width signal modulation circuit to continuously output a pulse width signal with a preset duty ratio for a first preset time so as to enable the second transistor to be closed, and after the first transistor and the second transistor are closed, powering on and closing the relay coil;
step 330, obtaining the coil current value flowing through the sampling resistor, and adjusting the duty ratio of the pulse width signal until the coil current value meets the preset coil current value range;
Step 340, controlling the pulse width signal modulation circuit to send an off signal to the first transistor and the second transistor to turn off the first transistor and the second transistor.
In step 310 of some embodiments, the pulse width signal modulation circuit sends a close signal to the first transistor to control the state of the first transistor. When the first transistor is closed, the first transistor is turned on, and current is allowed to pass; conversely, when it is off, the current will be blocked. By controlling the opening and closing states of the first transistor, the functions or performances of the whole circuit can be influenced, and the control and adjustment of the circuit are realized.
In step 320 of some embodiments, the pulse width signal modulation circuit will continuously output a pulse width signal for a preset time and ensure that the signal has a preset duty cycle. This signal will be used to control the state of the second transistor to be closed. When the first transistor and the second transistor are simultaneously closed, the relay coil in the circuit will energize and close. Such a sequence of operations may be for example to implement particular control logic or actions, such as establishing particular connections or paths in a circuit for subsequent execution of more complex functions or operations. By this step it is ensured that the second transistor is closed in accordance with predetermined signal parameters, eventually leading to the energizing and closing of the relay coil, completing the required control action.
In some embodiments, the closing action of the second transistor may be controlled by outputting a pulse width signal with a 100% duty cycle for 100 milliseconds. When the second transistor receives such a pulse width signal of 100% duty cycle, the closing operation is completed. The duration of the pulse width signal can be adjusted according to the actual requirements and the system design and the specification and performance requirements of the relay so as to ensure the normal operation of the system and meet the required function and performance indexes, and the embodiment is not limited.
In step 330 of some embodiments, the current condition of the coil can be known in real time by detecting the coil current value of the sampling resistor, and the duty ratio of the pulse width signal can be adjusted according to the detected current value, so as to control the current of the coil to reach the preset coil current value range. The control system can ensure that the coil current is kept within a set range, thereby realizing the purpose of accurately adjusting and controlling the coil current. By continuously detecting the current value and adjusting the control signal, it is possible to keep the coil current stably operating within a desired range.
In step 340 of some embodiments, the pulse width signal modulation circuit sends a disconnect signal to the first transistor and the second transistor, causing them to disconnect. By this operation, the first transistor and the second transistor will stop on-current, completing the turn-off process of the circuit portion controlled by them.
Referring to fig. 4, according to some embodiments of the present invention, the coil current value range includes a first coil current value and a second coil current value, wherein the first coil current value is greater than the second coil current value, and step 330 adjusts the duty cycle of the pulse width signal until the coil current value meets the preset coil current value range may include, but is not limited to, the following steps:
Step 410, when the coil current value is greater than the preset first coil current value, decreasing the duty cycle of the pulse width signal to make the coil current value smaller than the first coil current value;
In step 420, when the coil current value is smaller than the preset second coil current value, the duty cycle of the pulse width signal is increased to make the coil current value larger than the second coil current value.
In step 410 of some embodiments, when the coil current value exceeds a preset first coil current value, the pulse width signal modulation circuit may reduce the current value by reducing the duty cycle of the pulse width signal to ensure that the coil current remains below the first coil current value. This process is to avoid excessive current flow that may cause system damage or performance degradation. By dynamically adjusting the duty cycle of the pulse width signal, the system can effectively control the coil current to remain within a safe range.
In step 420 of some embodiments, when the coil current value is lower than the preset second coil current value, the pulse width signal modulation circuit may increase the duty cycle of the pulse width signal to increase the coil current, ensuring that the current value reaches or exceeds the second coil current value. This step is intended to maintain the coil current within a set range to ensure that the system is operating properly and meeting performance requirements. By dynamically adjusting the duty cycle of the pulse width signal, the system can precisely control the coil current to maintain it at a set desired level, thereby preventing the controlled relay from turning off unexpectedly due to too little current.
Referring to fig. 5, after adjusting the duty cycle of the pulse width signal until the coil current value meets the preset coil current range value in step 330 according to some embodiments of the present invention, the method may further include, but is not limited to, the following steps:
step 510, outputting the same synchronous pulse width signal according to the pulse width signal, and transmitting the synchronous pulse width signal to a pulse width modulation synchronous circuit of the control circuit;
in step 520, the pwm synchronization circuit sends a synchronous pwm signal to the pwm control circuit of the control circuit, so that the pwm control circuit maintains the output of the pwm signal.
In steps 510-520 of some embodiments, after the frequency and duty cycle of the pulse width signals are determined, the micro-control chip may generate the same synchronous pulse width signals according to the frequency and duty cycle and transmit the same to the pulse width modulation synchronization circuit, and the circuit receives the synchronous pulse width signals output by the micro-control chip, dynamically tracks the changes of the signals, and generates pulse width signals with the same frequency and duty cycle and transmits the same pulse width signals to the pulse width modulation control circuit so as to maintain continuous output of the pulse width signals.
The pulse width modulation synchronous circuit monitors and dynamically tracks the synchronous pulse width signals output from the micro control chip in real time so as to ensure that the output pulse width signals are always synchronous with the synchronous pulse width signals of the micro control chip, and transmits the information to the pulse width modulation control circuit so as to keep the continuity and stability of the pulse width signals.
Referring to fig. 6, step 340 of controlling the pulse width signal modulation circuit to send an off signal to the first transistor and the second transistor to turn off the first transistor and the second transistor according to some embodiments of the present invention may include, but is not limited to, the following steps:
step 610, controlling the micro control chip to send a reset signal to a timing circuit of the control circuit, and starting timing after the timing circuit detects a disconnection signal to obtain timing data;
Step 620, outputting a disconnection signal to the latch circuit and the pulse width modulation control circuit of the control circuit when the timing data exceeds the first preset time;
In step 630, the latch circuit receives the off signal and turns off the output, the first transistor is turned off, the pulse width modulation control circuit receives the off signal and turns off the output of the pulse width signal, and the second transistor is turned off.
In steps 610-630 of some embodiments, during the closing process of the first transistor and the second transistor, the timing circuit starts timing after detecting the reset signal sent by the micro-control chip, and outputs an off signal to the latch circuit and the pulse width modulation control circuit after the timing circuit times out, and after the latch circuit and the pulse width modulation control circuit close the output, the first transistor and the second transistor are turned off, so that the controlled electronic component is turned off. The system can reliably disconnect the electronic components according to a specific flow when required by triggering a reset signal, ensure that the operation of the system is performed in a controlled state and provide necessary safety and stability.
Referring to FIG. 7, in some embodiments, a micro control chip (MCU) begins to operate after power-up, and a timing circuit begins to operate after MCU operation; the MCU receives an instruction of closing the relay, the output signal is transmitted to the latch circuit, the latch circuit outputs a keep-close signal and transmits the keep-close signal to the first transistor, and the first transistor receives the keep-close signal and keeps closed. The MCU outputs a 100% duty cycle signal for 100mS, the switch edge circuit receives the 100% duty cycle signal and outputs the 100% duty cycle signal to the second transistor, and the second transistor is closed after receiving the signal. At the moment, the relay coil is electrified to be closed, the MCU outputs a pulse width signal after 100ms, and the second transistor keeps outputting the pulse width signal after receiving the pulse width signal through the edge adjusting circuit. The coil is in an energized state and the relay continues to close. At this time, the MCU measures the current flowing through the sampling resistor (average current on the coil) by measuring the voltage value of the differential operational amplifier, and when the MCU detects that the current flowing through the sampling resistor exceeds the coil current allowed by the relay, the duty ratio of the pulse width signal is gradually reduced until the MCU detects that the coil current of the relay is in a reasonable range. And similarly, when the MCU detects that the current flowing through the sampling resistor is smaller than the current for keeping the relay closed, the duty ratio of the pulse width signal is gradually increased until the MCU detects that the current of the relay coil is in a reasonable range. When the frequency and the duty ratio of the pulse width signals output by the MCU are determined, the MCU outputs the pulse width signals with the same frequency and duty ratio to the pulse width modulation synchronous circuit, the pulse width modulation synchronous circuit outputs the same pulse width signals to the pulse width modulation control circuit, and the pulse width modulation synchronous circuit dynamically tracks the pulse width signals of the MCU in real time and transmits the pulse width signals to the pulse width modulation control circuit. The pulse width modulation control circuit maintains a pulse width signal output.
Referring to fig. 8, fig. 8 illustrates a hardware structure of an electronic device of another embodiment, the electronic device including:
the processor 801 may be implemented by a general-purpose CPU (central processing unit), a microprocessor, an application-specific integrated circuit (ApplicationSpecificIntegratedCircuit, ASIC), or one or more integrated circuits, etc. for executing related programs to implement the technical solution provided by the embodiments of the present application;
Memory 802 may be implemented in the form of read-only memory (ReadOnlyMemory, ROM), static storage, dynamic storage, or random access memory (RandomAccessMemory, RAM), among others. The memory 802 may store an operating system and other application programs, and when the technical solutions provided in the embodiments of the present disclosure are implemented by software or firmware, relevant program codes are stored in the memory 802, and the processor 801 invokes a control method based on pulse width modulation signals to execute the embodiments of the present disclosure;
An input/output interface 803 for implementing information input and output;
the communication interface 804 is configured to implement communication interaction between the device and other devices, and may implement communication in a wired manner (e.g., USB, network cable, etc.), or may implement communication in a wireless manner (e.g., mobile network, WIFI, bluetooth, etc.);
a bus 805 that transfers information between the various components of the device (e.g., the processor 801, the memory 802, the input/output interface 803, and the communication interface 804);
Wherein the processor 801, the memory 802, the input/output interface 803, and the communication interface 804 implement communication connection between each other inside the device through a bus 805.
Embodiments of the present application also provide a computer program product comprising a computer program. The processor of the computer device reads the computer program and executes it, causing the computer device to execute the control method based on the pulse width modulation signal as described above.
The terms "first," "second," "third," "fourth," and the like in the description of the present disclosure and in the above-described figures, if any, are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that the embodiments of the disclosure described herein may be capable of operation in sequences other than those illustrated or described herein, for example. Furthermore, the terms "comprises," "comprising," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed or inherent to such process, method, article, or apparatus.
It should be understood that in this disclosure, "at least one" means one or more, and "a plurality" means two or more. "and/or" for describing the association relationship of the association object, the representation may have three relationships, for example, "a and/or B" may represent: only a, only B and both a and B are present, wherein a, B may be singular or plural. The character "/" generally indicates that the context-dependent object is an "or" relationship. "at least one of" or the like means any combination of these items, including any combination of single item(s) or plural items(s). For example, at least one (one) of a, b or c may represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", wherein a, b, c may be single or plural.
It should be understood that in the description of the embodiments of the present application, plural (or multiple) means two or more, and that greater than, less than, exceeding, etc. are understood to not include the present number, and that greater than, less than, within, etc. are understood to include the present number.
In the several embodiments provided in the present disclosure, it should be understood that the disclosed systems, devices, and methods may be implemented in other manners. For example, the apparatus embodiments described above are merely illustrative, e.g., the division of elements is merely a logical functional division, and there may be additional divisions of actual implementation, e.g., multiple elements or components may be combined or integrated into another system, or some features may be omitted, or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, which may be in electrical, mechanical or other form.
The units described as separate units may or may not be physically separate, and units shown as units may or may not be physical units, may be located in one place, or may be distributed over a plurality of network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.
In addition, each functional unit in each embodiment of the present disclosure may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit. The integrated units may be implemented in hardware or in software functional units.
The integrated units, if implemented in the form of software functional units and sold or used as stand-alone products, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present disclosure may be embodied in essence or a part contributing to the prior art or all or part of the technical solution in the form of a software product stored in a storage medium, including several instructions to cause a computer device (which may be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods of the various embodiments of the present disclosure. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a random access Memory (Random Access Memory RAM), a magnetic disk, or an optical disk, etc., which can store program codes.
It should also be appreciated that the various embodiments provided by the embodiments of the present application may be arbitrarily combined to achieve different technical effects.
The above is a specific description of the embodiments of the present disclosure, but the present disclosure is not limited to the above embodiments, and various equivalent modifications and substitutions can be made by those skilled in the art without departing from the spirit of the present disclosure, and are included in the scope of the present disclosure as defined in the claims.
Claims (9)
1. The control circuit based on the pulse width modulation signal is characterized by being applied to an automatic test stage of the battery module and comprising the following components:
The pulse width modulation power circuit comprises a first diode, a filter circuit, a first transistor, a second diode, a sampling resistor and a second transistor which are sequentially connected; the anode of the first diode is connected with the positive electrode of the power supply, the cathode of the first diode is connected with the input end of the filter circuit, the output end of the filter circuit is connected with the drain electrode of the first transistor, the source electrode of the first transistor is connected with the cathode of the second diode, the anode of the second diode is connected with one end of the sampling resistor, the other end of the sampling resistor is connected with the drain electrode of the second transistor, and the source electrode of the second transistor is grounded;
The two input ports of the differential amplifying circuit are respectively connected with two ends of the sampling resistor;
The third port of the pulse width signal modulation circuit is connected with the grid electrode of the first transistor, the fourth port of the pulse width signal modulation circuit is connected with the output port of the differential amplifying circuit, and the fifth port of the pulse width signal modulation circuit is connected with the grid electrode of the second transistor; the pulse width signal modulation circuit sends a signal for controlling the first transistor to be closed to the gate of the first transistor through the third port, receives the signal amplified by the differential amplification circuit through the fourth port, and outputs a pulse width signal to the gate of the second transistor through the fifth port;
The pulse width signal modulation circuit also comprises a micro control chip, a latch circuit, a timing circuit, a pulse width modulation control circuit and a pulse width modulation synchronization circuit;
The latch circuit is connected with a seventh port of the micro control chip; the seventh port is an I/O port, and the micro control chip outputs a signal for controlling the first transistor to be closed to the latch circuit through the seventh port;
The timing circuit is connected with an eighth port of the micro control chip, and the timing circuit is connected with the latch circuit; the micro control chip sends a reset signal to the timing circuit through the eighth port so as to enable the timing circuit to time;
The pulse width modulation synchronous circuit is connected with a ninth port of the micro control chip; the micro control chip transmits the same pulse width signal to the pulse width modulation synchronous circuit through the ninth port according to the pulse width signal output to the second transistor;
the pulse width modulation control circuit is connected with the pulse width modulation synchronous circuit, the timing circuit is connected with the pulse width modulation control circuit, the pulse width modulation control circuit is connected with the grid electrode of the second transistor, and the latch circuit is connected with the grid electrode of the first transistor.
2. The control circuit of claim 1, wherein the pulse width signal modulation circuit further comprises a switching edge adjustment circuit connected to a tenth port of the micro-control chip and between the pulse width modulation control circuit and a gate of the second transistor.
3. The control circuit of claim 1, wherein two ends of the second diode are connected to two ends of the controlled electronic component by a twisted pair shielding harness.
4. A control method based on a pulse width modulation signal, applied to the control circuit based on a pulse width modulation signal as claimed in any one of claims 1 to 3, comprising:
Controlling a pulse width signal modulation circuit to send a closing signal to a first transistor so as to enable the first transistor to be closed;
Controlling the pulse width signal modulation circuit to continuously output a pulse width signal with a preset duty ratio for a first preset time so as to enable the second transistor to be closed, and after the first transistor and the second transistor are closed, electrifying the relay coil to be closed;
Acquiring a coil current value flowing through a sampling resistor, and adjusting the duty ratio of the pulse width signal until the coil current value meets a preset coil current value range;
And controlling the pulse width signal modulation circuit to send an off signal to the first transistor and the second transistor so as to turn off the first transistor and the second transistor.
5. The control method of claim 4, wherein the range of coil current values includes a first coil current value and a second coil current value, wherein the first coil current value is greater than the second coil current value, and wherein adjusting the duty cycle of the pulse width signal until the coil current value meets a preset range of coil current values comprises:
When the coil current value is larger than the preset first coil current value, the duty ratio of the pulse width signal is reduced so that the coil current value is smaller than the first coil current value;
And when the coil current value is smaller than the preset second coil current value, increasing the duty ratio of the pulse width signal so that the coil current value is larger than the second coil current value.
6. The control method according to claim 4, characterized by further comprising, after said adjusting the duty ratio of the pulse width signal until the coil current value satisfies a preset coil current range value:
The same synchronous pulse width signal is output according to the pulse width signal, and the synchronous pulse width signal is transmitted to a pulse width modulation synchronous circuit of the control circuit;
The pulse width modulation synchronization circuit sends the synchronous pulse width signal to a pulse width modulation control circuit of the control circuit so that the pulse width modulation control circuit keeps outputting the pulse width signal.
7. The control method according to claim 4, wherein the controlling the pulse width signal modulation circuit to send an off signal to the first transistor and the second transistor to turn off the first transistor and the second transistor includes:
The control micro-control chip sends a reset signal to a timing circuit of the control circuit, and when the timing circuit detects the disconnection signal, timing is started to obtain timing data;
Outputting the disconnection signal to a latch circuit of the control circuit and the pulse width modulation control circuit when the timing data exceeds a first preset time;
the latch circuit receives the disconnection signal and then turns off the output, the first transistor is disconnected, the pulse width modulation control circuit receives the disconnection signal and then turns off the output of the pulse width signal, and the second transistor is disconnected.
8. An electronic device, comprising: a memory, a processor storing a computer program, the processor implementing the pulse width modulation signal based control method according to any one of claims 4 to 7 when executing the computer program.
9. A computer-readable storage medium, characterized in that the storage medium stores a program that is executed by a processor to realize the pulse width modulation signal-based control method according to any one of claims 4 to 7.
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| US7804200B2 (en) * | 2008-04-21 | 2010-09-28 | Tyco Electronics Corporation | Photosensor circuits including a switch mode power converter |
| US20100177542A1 (en) * | 2009-01-09 | 2010-07-15 | Richtek Technology Corp. | Power transistor chip with built-in start-up transistor and application circuiyt thereof |
| CN103683204A (en) * | 2012-09-26 | 2014-03-26 | 深圳市海洋王照明工程有限公司 | Switching power supply over-current protection circuit |
| CN103151824B (en) * | 2013-03-29 | 2015-08-05 | 哈尔滨工业大学 | Lithium cell charging control circuit |
| CN116846189A (en) * | 2023-06-30 | 2023-10-03 | 骏盈半导体(上海)有限公司 | ACOT control circuit and chip applied to voltage converter |
| CN118009865B (en) * | 2024-04-09 | 2024-06-21 | 浙江大学 | Programmable displacement signal conditioning method and system for electrohydraulic control valve |
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