A PWM drive circuit

Abstract

The present application provides a PWM driving circuit. The PWM driving circuit provided by the present application can sense the driving signal output by the control circuit through the first sensing circuit to generate a first sensing signal and send it to the controller, and can sense the third PWM signal output by the driving circuit through the second sensing circuit to generate a second sensing signal and send it to the controller. The controller can determine whether there is an abnormality in the PWM driving circuit and the location where the abnormality occurs based on the second PWM signal, the first sensing signal, the second sensing signal, and the first PWM signal output by itself to the PWM driving circuit. In this way, a PWM driving circuit with an abnormality detection function can be provided, which can accurately identify whether there is an abnormality in the PWM signal, quickly locate the abnormality position, and improve the reliability and safety of the circuit.

Description

Technical Field

[0001] This application relates to the technical field of electronic appliances, and particularly to a PWM drive circuit. Background Art

[0002] The PWM (Pulse Width Modulation) drive circuit is a technology that uses the digital output of a microprocessor to control analog circuits, and is widely used in many fields such as measurement, communication, power control and conversion.

[0003] The PWM drive circuit can adjust the output power by controlling the width of the pulse signal, so as to efficiently and accurately adjust the motor speed, LED brightness, heater power, etc. It is widely used in fields such as power conversion, audio signal synthesis, communication systems and robot control.

[0004] Currently, the PWM drive circuit still has some technical defects. For example, when the circuit is abnormal, it is impossible to quickly find the specific location where the abnormality occurs. Summary of the Invention

[0005] In view of this, this application provides a PWM drive circuit, which has an abnormality detection function and can detect whether there is an abnormality in the PWM drive circuit, and quickly locate the position where the abnormality occurs when the PWM drive circuit is abnormal.

[0006] Specifically, this application is implemented through the following technical solutions:

[0007] This application provides a PWM drive circuit, which includes an isolation circuit, a control circuit, a drive circuit, a first sensing circuit, a second sensing circuit and a controller; wherein,

[0008] The input end of the isolation circuit is used to receive the first PWM signal from the controller; the output end of the isolation circuit is respectively connected to the input end of the control circuit and the controller; the isolation circuit is used to achieve electrical isolation and convert the first PWM signal into a second PWM signal and output it to the control circuit and the controller;

[0009] The power supply end of the control circuit is connected to a DC drive voltage source; the output end of the control circuit is connected to the input end of the drive circuit and the input end of the first sensing circuit; the control circuit is used to generate a drive signal for driving the drive circuit according to the second PWM signal;

[0010] The power supply terminal of the driving circuit is connected to the DC driving voltage source, and the output terminal of the driving circuit is respectively connected to the load to be driven and the input terminal of the second sensing circuit; the driving circuit is configured to generate a third PWM signal for driving the load under the control of the driving signal;

[0011] The output terminals of the first sensing circuit and the second sensing circuit are respectively connected to the controller; wherein, the first sensing circuit is configured to sense the driving signal generated by the control circuit and feed the sensed first sensing signal back to the controller; the second sensing circuit is configured to sense the third PWM signal generated by the driving circuit and feed the sensed second sensing signal back to the controller;

[0012] The controller is configured to determine whether there is an abnormality in the PWM driving circuit and the location where the abnormality occurs according to the first PWM signal, the second PWM signal, the first sensing signal and the second sensing signal.

[0013] The PWM driving circuit provided by the present application can form a PWM driving circuit by setting an isolation circuit, a control circuit and a driving circuit, and electrical isolation can be achieved by setting the isolation circuit. Further, by connecting the output terminal of the isolation circuit to the controller and further setting the first sensing circuit and the second sensing circuit, in this way, the driving signal output by the control circuit can be sensed by the first sensing circuit to generate a first sensing signal and sent to the controller, and the third PWM signal output by the driving circuit can be sensed by the second sensing circuit to generate a second sensing signal and sent to the controller. In this way, the controller can determine whether there is an abnormality in the PWM driving circuit and the location where the abnormality occurs according to the second PWM signal output by the isolation circuit, the first sensing signal sensed by the first sensing circuit, the second sensing signal sensed by the second sensing circuit, and the first PWM signal output by itself to the PWM driving circuit. In this way, a PWM driving circuit with an abnormality detection function can be provided, which can accurately identify whether there is an abnormality in the PWM signal, quickly locate the abnormality location, and improve the reliability and safety of the circuit.

[0014] Further, the PWM driving circuit provided by the present application can collect the current of the load by setting a load current acquisition circuit, and feed the collected current value back to the controller. The controller can judge whether the load is abnormal according to the detected current value. In this way, the working state of the load can be further detected, the reliability and safety of the PWM driving circuit can be significantly improved, overload and faults of the load can be prevented, and preventive maintenance and intelligent control can be realized.

[0015] Further, when the PWM drive circuit provided in this application determines that there is no abnormality based on the status information of the second PWM signal, the status information of the first sensing signal, and the status information of the second sensing signal, further, for any one of the second PWM signal, the first sensing signal, and the second sensing signal, by obtaining the voltage value corresponding to the signal, and based on the voltage value corresponding to the signal and the preset voltage range corresponding to the signal, determine the health status of the circuit module corresponding to the signal, and then display the health status of each circuit module to the user, so that the user can understand the health status of each circuit module. In this way, based on the voltage values corresponding to each signal, the health status of the corresponding circuit module can be accurately determined, which can not only improve the accuracy of abnormality detection, but also present the health status of each circuit module to the user, enabling the user to intuitively understand the working condition of the circuit, promoting preventive maintenance and optimized management.

[0016] Further, for the PWM drive circuit provided in this application, for any one of the second PWM signal, the first sensing signal, and the second sensing signal, by calculating the difference value between the voltage value corresponding to the signal and the standard voltage value corresponding to the signal, and based on the difference value and the preset correspondence between the difference value and the health level, determine the health level of the circuit module corresponding to the signal, and then display the health level of each circuit module to the user. In this way, the health levels of each circuit module can be monitored and evaluated in real time, the operating status of each circuit module can be predicted in advance, and the circuit module can be replaced in a timely manner, which can improve the reliability and safety of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematic diagram of the first embodiment of the PWM drive circuit provided in this application;

[0018] Figure 2 Schematic diagram of the second embodiment of the PWM drive circuit provided in this application;

[0019] Figure 3 Circuit schematic diagram of the PWM drive circuit shown in an exemplary embodiment of this application;

[0020] Figure 4 Circuit schematic diagram of the PWM drive circuit shown in another exemplary embodiment of this application.

[0021] Description of the reference numerals:

[0022] 1: Isolation circuit;

[0023] 2: Control circuit;

[0024] 3: Drive circuit;

[0025] 4: First sensing circuit;

[0026] 5: Second sensing circuit;

[0027] 6: Controller;

[0028] 7: Load current acquisition circuit;

[0029] Q1: Triode;

[0030] M1: MOS transistor;

[0031] D1: Zener diode;

[0032] R41: The first resistor in the first sensing circuit;

[0033] R42: The second resistor in the first sensing circuit;

[0034] R51: The first resistor in the second sensing circuit;

[0035] R52: The second resistor in the second sensing circuit;

[0036] R3: The third resistor. Detailed implementation mode

[0037] Here, the exemplary embodiments will be described in detail, and the examples are shown in the drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application.

[0038] The terms used in the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. The singular forms "a", "the" and "said" used in the present application are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0039] It should be understood that although the terms first, second, third, etc. may be used in the present application to describe various information, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "when" or "while" or "in response to a determination".

[0040] Specific embodiments are given below to introduce the technical solutions of the present application in detail.

[0041] Figure 1Schematic diagram of the first embodiment of the PWM driving circuit provided by this application. Please refer to Figure 1 , the PWM driving circuit provided in this embodiment includes an isolation circuit 1, a control circuit 2, a driving circuit 3, a first sensing circuit 4, a second sensing circuit 5, and a controller 6; among them,

[0042] The input end of the isolation circuit 1 is used to receive the first PWM signal from the controller 6; the output end of the isolation circuit 1 is respectively connected to the input end of the control circuit 2 and the controller 6; the isolation circuit 1 is used to achieve electrical isolation and convert the first PWM signal into a second PWM signal and output it to the control circuit 2 and the controller 6;

[0043] The power supply end of the control circuit 2 is connected to a DC driving voltage source; the output end of the control circuit 2 is connected to the input end of the driving circuit 3 and the input end of the first sensing circuit 4; the control circuit 2 is used to generate a driving signal for driving the driving circuit 3 according to the second PWM signal;

[0044] The power supply end of the driving circuit 3 is connected to the DC driving voltage source, and the output end of the driving circuit 3 is respectively connected to the load to be driven and the input end of the second sensing circuit 5; the driving circuit 3 is used to generate a third PWM signal for driving the load under the control of the driving signal;

[0045] The output ends of the first sensing circuit 4 and the second sensing circuit 5 are respectively connected to the controller 6; among them, the first sensing circuit 4 is used to sense the driving signal generated by the control circuit 2 and feed the sensed first sensing signal back to the controller 6; the second sensing circuit 5 is used to sense the third PWM signal generated by the driving circuit 3 and feed the sensed second sensing signal back to the controller 6;

[0046] The controller 6 is used to determine whether there is an abnormality in the PWM driving circuit and the location where the abnormality occurs according to the first PWM signal, the second PWM signal, the first sensing signal, and the second sensing signal.

[0047] Specifically, the isolation circuit 1 is a circuit used to prevent current from directly conducting between two circuits, but allows signals and energy to be transmitted in a certain way. In this application, the isolation circuit 1 can separate high-voltage or high-power circuits from low-voltage or low-power control circuits, protect the control circuit 2 from high-voltage impacts or noise interference, and reduce the influence of external electromagnetic interference on the PWM signal during the PWM signal transmission process.

[0048] Further, the isolation circuit 1 can be an isolation circuit composed of an optocoupler, an isolation circuit composed of a magnetic coupler, etc. Optionally, in a possible implementation, the isolation circuit 1 is an isolation circuit composed of a pulse transformer.

[0049] Specifically, when the isolation circuit 1 is an isolation circuit composed of a pulse transformer, it isolates signals through magnetic induction, converts the input first PWM signal into a magnetic signal and transmits it to the secondary side, and then converts it back into an electrical signal at the secondary side, so as to achieve electrical isolation between the input first PWM signal and the output second PWM signal, ensure that there is no direct electrical connection between the two, prevent high voltage or noise from being transmitted from the input side to the load side, and thus protect the circuit and the controller 6.

[0050] Specifically, please continue to refer to Figure 1 , the power supply terminal of the control circuit 2 is connected to the DC drive voltage source, and the DC drive voltage source is used to provide the necessary operating voltage for the control circuit 2. Further, the control circuit 2 is arranged between the isolation circuit 1 and the drive circuit 3. The control circuit 2 is used to generate a drive signal according to the second PWM signal, and then transmit the drive signal to the drive circuit 3 to drive the above drive circuit 3 with the drive signal. In addition, the output terminal of the control circuit 2 is also connected to the input terminal of the first sensing circuit 4, and is used to send the second PWM signal to the first sensing circuit 4 for monitoring or feedback.

[0051] Optionally, in a possible implementation, the control circuit 2 can be a circuit composed of a triode, and in this embodiment, it is not limited.

[0052] It should be noted that the specific voltage value of the DC drive voltage source is set according to actual needs, and it is not limited in this embodiment.

[0053] Specifically, please continue to refer to Figure 1 , the power supply terminal of the drive circuit 3 is connected to the DC drive voltage source, and the DC drive voltage source provides the necessary operating circuit for the drive circuit 3. Further, the input terminal of the drive circuit 3 is connected to the control circuit 2, and the output terminal of the drive circuit 3 is connected to the load to be driven. The drive circuit 3 is used to receive the drive signal generated by the control circuit 2 and generate a third PWM signal under the control of the drive signal, and the third PWM signal is further transmitted to the load to be driven to drive the load to work.

[0054] It should be noted that the load to be driven is set according to actual needs, and it is not limited in this embodiment. For example, in a possible implementation, the load to be driven is a motor.

[0055] In addition, the output terminal of the drive circuit 3 is also connected to the input terminal of the second sensing circuit 5, for sending the third PWM signal to the second sensing circuit 5 for monitoring or feedback.

[0056] Specifically, please continue to refer to Figure 1 , the input terminal of the first sensing circuit 4 is connected to the output terminal of the control circuit 2, and the output terminal of the first sensing circuit 4 is connected to the controller 6; the first sensing circuit 4 is mainly used for sensing the drive signal generated by the control circuit 2, and then feeding the sensed first sensing signal back to the controller 6.

[0057] Furthermore, the input terminal of the second sensing circuit 5 is connected to the output terminal of the drive circuit 3, and the output terminal of the second sensing circuit 5 is connected to the controller 6; the second sensing circuit 5 is mainly used for sensing the third PWM signal generated by the drive circuit 3, and feeding the sensed second sensing signal back to the controller 6.

[0058] Optionally, in a possible implementation manner, the first sensing circuit 4 and the second sensing circuit 5 may be voltage dividing circuits, which are not limited in this embodiment.

[0059] Specifically, please continue to refer to Figure 1 , the controller 6 is respectively connected to the output terminal of the isolation circuit 1, the output terminal of the first sensing circuit 4, and the output terminal of the second sensing circuit 5. It receives the second PWM signal from the isolation circuit 1, the first sensing signal from the first sensing circuit 4, and the second sensing signal from the second sensing circuit 5. It can determine whether there is an abnormality in the PWM drive circuit and the location where the abnormality occurs according to the second PWM signal, the first sensing signal, and the second sensing signal.

[0060] In specific implementation, for example, the controller 6 can judge whether there is an abnormality in the isolation circuit 1 according to whether the second PWM signal is abnormal. When the second PWM signal is abnormal, it is determined that the isolation circuit 1 is abnormal, otherwise it is determined that the isolation circuit 1 is normal. Similarly, the controller 6 can determine whether there is an abnormality in the control circuit 2 according to the first sensing signal. When the first sensing signal is abnormal, it is determined that the control circuit 2 is abnormal, otherwise it is determined that the control circuit 2 is normal. Similarly, the controller 6 can also judge whether the drive circuit 3 is abnormal according to the second sensing signal. When the second sensing signal is abnormal, it is determined that the drive circuit 3 is abnormal, otherwise it is determined that the drive circuit 3 is normal.

[0061] Specifically, for example, in a possible implementation manner, after the controller 6 issues the first PWM signal, the controller 6 cannot detect the subsequent signal, and thus it can be determined that the location where the abnormality occurs is the isolation circuit 1.

[0062] For another example, in another embodiment, after the controller 6 issues the first PWM signal, the controller 6 only detects the second PWM signal and does not detect the first sensing signal and the second sensing signal. Thus, it can be determined that the location where the abnormality occurs is the control circuit 2.

[0063] For another example, after the controller 6 issues the first PWM signal, the controller 6 detects the second PWM signal and the first sensing signal and does not detect the second sensing signal. Thus, it can be determined that the location where the abnormality occurs is the drive circuit 3.

[0064] Optionally, in a possible implementation manner, the controller 6 is specifically configured to:

[0065] For any one of the second PWM signal, the first sensing signal, and the second sensing signal, determine whether the signal is abnormal according to the number of pulses included in the signal and the number of pulses included in the first PWM signal, and obtain status information indicating whether the signal is abnormal;

[0066] According to the status information of the second PWM signal, the status information of the first sensing signal, and the status information of the second sensing signal, determine whether there is an abnormality in the PWM drive circuit and the location where the abnormality occurs.

[0067] It should be noted that both the input and output of the PWM drive circuit are PWM signals. In a normal state, that is, when there is no abnormality in the PWM drive circuit, the number of pulses included in the first PWM signal issued by the controller 6, the number of pulses included in the second PWM signal output by the isolation circuit 1, the number of pulses included in the drive signal generated by the control circuit 2, and the number of pulses included in the third PWM signal generated by the drive circuit 3 should be equal. The number of pulses included in the first sensing signal sensed by the first sensing circuit 4 and the number of pulses included in the second pulse sensed by the second sensing circuit 5 should also be equal to the number of pulses included in the first PWM signal. Therefore, for any one of the second PWM signal, the first sensing signal, and the second sensing signal, it is possible to determine whether the signal is abnormal according to the number of pulses included in the signal and the number of pulses included in the first PWM signal, and obtain status information indicating whether the signal is abnormal. For example, when the number of pulses included in the signal is equal to the number of pulses included in the first PWM signal, the status information of the signal is determined to be normal, and when the number of pulses included in the signal is not equal to the number of pulses included in the first PWM signal, the status information of the signal is determined to be abnormal.

[0068] Combined with the above introduction, for example, in a possible implementation, the controller 6 issues a first PWM signal. The number of pulses included in the first PWM signal is 100. The isolation circuit 1 receives the first PWM signal and issues a second PWM signal. The control circuit 2 receives the second PWM signal and issues a drive signal. The first sensing circuit 4 senses the drive signal and generates a first sensing signal. Further, the drive circuit 3 receives the drive signal and generates a third PWM signal. The second sensing circuit 5 senses the third PWM signal and generates a second sensing signal. At this time, the controller 6 detects that the number of pulses included in the second PWM signal is 100, the number of pulses included in the first sensing signal is 90, and the number of pulses included in the second sensing signal is 90. At this time, it indicates that the first sensing signal and the second sensing signal are abnormal, and the status information of the first sensing signal and the second sensing signal is abnormal.

[0069] For another example, in another possible implementation, the controller 6 issues a first PWM signal. The number of pulses included in the first PWM signal is 100. The isolation circuit 1 receives the first PWM signal and issues a second PWM signal. The control circuit 2 receives the second PWM signal and issues a drive signal. The first sensing circuit 4 senses the drive signal and generates a first sensing signal. Further, the drive circuit 3 receives the drive signal and generates a third PWM signal. The second sensing circuit 5 senses the third PWM signal and generates a second sensing signal. At this time, the controller 6 detects that the number of pulses included in the second PWM signal is 100, the number of pulses included in the first sensing signal is 90, and the number of pulses included in the second sensing signal is 80. At this time, it indicates that the first sensing signal and the second sensing signal are abnormal, and the status information of the first sensing signal and the second sensing signal is abnormal.

[0070] It should be noted that the number of pulses included in the first PWM signal is determined by actual needs and is not limited in this embodiment.

[0071] Please continue to refer to Figure 1 , optionally, in a possible implementation, according to the status information of the second PWM signal, the status information of the first sensing signal, and the status information of the second sensing signal, determining whether there is an abnormality in the PWM drive circuit and the location where the abnormality occurs includes:

[0072] (1) When the status information of the second PWM signal is abnormal, it is determined that there is an abnormality in the PWM drive circuit, and the location where the abnormality occurs is determined to be the isolation circuit.

[0073] Specifically, in combination with the above introduction, when the controller 6 fails to detect the second PWM signal or the number of pulses contained in the detected second PWM signal is not equal to the number of pulses contained in the first PWM signal, it is determined that the location where the abnormality occurs is the isolation circuit 1.

[0074] (2) When the status information of the second PWM signal is normal and the status information of the first sensing signal is abnormal, it is determined that there is an abnormality in the PWM driving circuit, and the location where the abnormality occurs is determined to be the control circuit.

[0075] Specifically, in combination with the above introduction, for example, the controller 6 issues a first PWM signal, the number of pulses contained in the first PWM signal is 100, the number of pulses contained in the first sensing signal detected by the controller 6 is 90, and the number of pulses contained in the second sensing signal is 90. At this time, it indicates that the first sensing signal and the second sensing signal are abnormal, and the status information of the first sensing signal and the second sensing signal is abnormal. Since the number of pulses contained in the second sensing signal is equal to the number of pulses contained in the first sensing signal, it is determined that the abnormality of the second sensing signal is caused by the abnormality of the first sensing signal, and then the location where the abnormality occurs is determined to be the control circuit 2.

[0076] (3) When the status information of the second PWM signal is normal, the status information of the first sensing signal is normal, and the status information of the second sensing signal is abnormal, it is determined that there is an abnormality in the PWM driving circuit, and the location where the abnormality occurs is determined to be the driving circuit 3.

[0077] Specifically, in combination with the above introduction, when the controller 6 fails to detect the second sensing signal or the number of pulses contained in the detected second sensing signal is not equal to the number of pulses contained in the first sensing signal, it is determined that the location where the abnormality occurs is the driving circuit 3.

[0078] The PWM drive circuit provided in this embodiment can form a PWM drive circuit by setting an isolation circuit, a control circuit, and a drive circuit. Moreover, by setting the isolation circuit, electrical isolation can be achieved. Further, by connecting the output end of the isolation circuit to the controller and further setting a first sensing circuit and a second sensing circuit, in this way, the drive signal output by the control circuit can be sensed by the first sensing circuit to generate a first sensing signal and sent to the controller, and the third PWM signal output by the drive circuit can be sensed by the second sensing circuit to generate a second sensing signal and sent to the controller. Thus, the controller can determine whether there is an abnormality in the PWM drive circuit and the location where the abnormality occurs based on the second PWM signal output by the isolation circuit, the first sensing signal sensed by the first sensing circuit, the second sensing signal sensed by the second sensing circuit, and the first PWM signal output by itself to the PWM drive circuit. In this way, a PWM drive circuit with an abnormality detection function can be provided, which can accurately identify whether there is an abnormality in the PWM signal, quickly locate the abnormality position, and improve the reliability and safety of the circuit.

[0079] Figure 2 It is a schematic diagram of Embodiment 2 of the PWM drive circuit provided in this application. Please refer to Figure 2 , on the basis of the above embodiment, the PWM drive circuit provided in this embodiment further includes a load current acquisition circuit 7; wherein,

[0080] The load current acquisition circuit 7 is used to acquire the current of the load and feedback the acquired current value to the controller 6.

[0081] The controller 6 is further used to judge whether the load is abnormal according to the current value.

[0082] Specifically, when the controller 6 detects that the current value of the load exceeds the normal working range, it determines that the load is abnormal.

[0083] It should be noted that the normal working range of the load current is set according to actual needs and is not limited in this embodiment. For example, in a possible implementation, the normal working range of the load current is 15 - 30A. If the controller 6 detects that the current value of the load is outside 15 - 30A, it determines that the load is abnormal.

[0084] The PWM drive circuit provided in this embodiment can, by setting a load current acquisition circuit, acquire the current of the load by using the load current acquisition circuit and feedback the acquired current value to the controller. The controller can then judge whether the load is abnormal according to the detected current value. In this way, the working state of the load can be further detected, the reliability and safety of the PWM drive circuit can be significantly improved, overload and faults of the load can be prevented, and preventive maintenance and intelligent control can be realized.

[0085] Optionally, in a possible implementation manner, the controller 6 is further configured to:

[0086] When it is determined that the PWM driving circuit is normal according to the state information of the second PWM signal, the state information of the first sensing signal, and the state information of the second sensing signal, for any one of the second PWM signal, the first sensing signal, and the second sensing signal, obtain the voltage value corresponding to this signal;

[0087] According to the voltage value corresponding to this signal and the preset voltage range corresponding to this signal, determine the health state of the circuit module corresponding to this signal; wherein, the health state is used to indicate whether there is an abnormality in the circuit module;

[0088] Display the health states of each circuit module to the user, so that the user can understand the health states of each circuit module.

[0089] Specifically, for any one of the second PWM signal, the first sensing signal, and the second sensing signal, the controller 6 can perform analog-to-digital conversion on this signal to obtain the voltage value corresponding to this signal.

[0090] Furthermore, the preset voltage range corresponding to any one of the second PWM signal, the first sensing signal, and the second sensing signal is set according to actual needs, and in this embodiment, it is not limited. In addition, the preset voltage ranges corresponding to each signal may be the same or different, and in this embodiment, it is not limited. For example, in one embodiment, the preset voltage ranges corresponding to each signal are shown in Table 1:

[0091] Table 1 Each signal and its corresponding preset voltage range

[0092]

[0093] In specific implementation, for a certain signal, if the voltage value corresponding to this signal is within the preset voltage range corresponding to this signal, determine that the health state of the circuit module corresponding to this signal is healthy, otherwise determine that the health state of the circuit module corresponding to this signal is unhealthy.

[0094] For example, when the voltage value of the second PWM signal is outside its corresponding preset voltage range, it is determined that the health state of the circuit module corresponding to this signal is unhealthy, that is, the health state of the isolation circuit 1 is unhealthy; similarly, when the voltage value of the first sensing signal is outside its corresponding preset voltage range, it is determined that the health state of the circuit module corresponding to this signal is abnormal, that is, the health state of the control circuit 2 is unhealthy; similarly, when the voltage value of the second sensing signal is outside its corresponding preset voltage range, it is determined that the health state of the circuit module corresponding to this signal is unhealthy, that is, the health state of the drive circuit 3 is unhealthy.

[0095] When the PWM drive circuit provided in this embodiment determines that there is no abnormality in the PWM drive circuit according to the status information of the second PWM signal, the status information of the first sensing signal, and the status information of the second sensing signal, further, for any one of the second PWM signal, the first sensing signal, and the second sensing signal, by obtaining the voltage value corresponding to this signal, and according to the voltage value corresponding to this signal and the preset voltage range corresponding to this signal, determine the health state of the circuit module corresponding to this signal, and then display the health state of each circuit module to the user, so that the user can understand the health state of each circuit module. In this way, based on the voltage values corresponding to each signal, the health state of the corresponding circuit module can be accurately determined, which can not only improve the accuracy of anomaly detection, but also give the health state of each circuit module to the user, enabling the user to intuitively understand the working condition of the circuit, promoting preventive maintenance and optimized management.

[0096] Optionally, in a possible implementation manner, on the basis of the above embodiment, the controller 6 is further configured to:

[0097] For any one of the second PWM signal, the first sensing signal, and the second sensing signal, calculate the difference value between the voltage value corresponding to this signal and the standard voltage value corresponding to this signal.

[0098] According to the difference value and the corresponding relationship between the preset difference value and the health level, determine the health level of the circuit module corresponding to this signal.

[0099] Display the health levels of each circuit module to the user.

[0100] Specifically, the standard voltage value corresponding to each signal is set according to actual needs and is not limited in this embodiment. Further, the absolute value of the difference between the actual voltage value of the signal and the standard voltage value, or the percentage of the absolute value of the difference between the actual voltage value and the standard voltage value relative to the standard voltage value can be determined as the difference value between the voltage value corresponding to the signal and the standard voltage value corresponding to the signal, which is not limited in this embodiment. Hereinafter, an example will be given by taking the percentage of the absolute value of the difference between the actual voltage value and the standard voltage value relative to the standard voltage value as the difference value between the voltage value corresponding to the signal and the standard voltage value corresponding to the signal.

[0101] For example, in a possible implementation manner, when calculating the difference value between the voltage value corresponding to the signal and the standard voltage value corresponding to the signal, the following formula can be used for calculation:

[0102] ;

[0103] Wherein, is the difference value between the voltage value corresponding to the signal and the standard voltage value corresponding to the signal;

[0104] U 1 is the voltage value corresponding to the signal;

[0105] U 0 is the standard voltage value corresponding to the signal.

[0106] Further, for each signal, the corresponding relationship between the preset difference value and the health level is set according to actual requirements and is not limited in this embodiment. In addition, for different signals, the corresponding relationship between the preset difference value and the health level can be the same or different.

[0107] For example, in a possible implementation manner, for different signals, the corresponding relationship between the preset difference value and the health level is the same. Table 2 shows the corresponding relationship between the preset difference value and the health level corresponding to each signal shown in an exemplary embodiment.

[0108] Table 2 Corresponding relationship between preset difference value and health level corresponding to each signal

[0109]

[0110] Please refer to Table 2 and combine with the examples shown in Table 1. For example, in a possible implementation, after calculation, it is determined that the difference value corresponding to the second PWM signal is 3%. At this time, it is determined that the health level of isolation circuit 1 is excellent; for another example, after calculation, it is determined that the difference value corresponding to the first sensing signal is 15%. At this time, it is determined that the health level of control circuit 2 is passing; for yet another example, it is determined that the difference value corresponding to the second sensing signal is 21%. At this time, it is determined that the health level of drive circuit 3 is failing.

[0111] Further, after determining the health levels of each circuit module, display the health levels of each circuit module to the user. The user can observe the health levels of each circuit module. When the health level of a circuit module is less than the available health level set by the user, the user can replace the corresponding circuit module, thereby increasing the stability and safety of the circuit operation.

[0112] For the PWM drive circuit provided in this embodiment, for any one of the second PWM signal, the first sensing signal, and the second sensing signal, calculate the difference value between the voltage value corresponding to this signal and the standard voltage value corresponding to this signal, and according to the difference value and the preset correspondence between the difference value and the health level, determine the health level of the circuit module corresponding to this signal. Furthermore, display the health levels of each circuit module to the user. In this way, the health levels of each circuit module can be monitored and evaluated in real time, the operating states of each circuit module can be predicted in advance, and the circuit modules can be replaced in a timely manner, which can improve the reliability and safety of the system.

[0113] Figure 3 It is a circuit schematic diagram of the PWM drive circuit shown in an exemplary embodiment of the present application. Figure 4 It is a circuit schematic diagram of the PWM drive circuit shown in another exemplary embodiment of the present application; please also refer to Figure 3 and Figure 4 , on the basis of the above embodiments, for the PWM drive circuit provided in this embodiment, the isolation circuit 1 is an isolation circuit 1 composed of a pulse transformer.

[0114] Further, optionally, the control circuit 2 includes a triode Q1 and a third resistor R3; wherein,

[0115] The base of the triode Q1 constitutes the input end of the control circuit 2 and is connected to the output end of the isolation circuit 1;

[0116] The first end of the third resistor R3 constitutes the power supply end of the control circuit 2 and is connected to the DC drive voltage source;

[0117] The second end of the third resistor R3 and the collector of the triode Q1 are connected to form the output end of the control circuit 2;

[0118] The emitter of the triode Q1 is grounded.

[0119] Optionally, please continue to refer to Figure 3 , for the PWM drive circuit provided in this embodiment, the drive circuit 3 includes a MOS transistor M1 and a zener diode D1; wherein,

[0120] The gate of the MOS transistor M1 constitutes the input end of the drive circuit 3 and is connected to the output end of the control circuit 2;

[0121] The source of the MOS transistor M1 constitutes the power supply end of the drive circuit 3 and is connected to the DC drive voltage source;

[0122] The drain of the MOS transistor M1 is connected to the positive electrode of the zener diode D1, and the negative electrode of the zener diode D1 is grounded.

[0123] Please continue to refer to Figure 3 and Figure 4 , the working principle of this PWM drive circuit is briefly introduced as follows:

[0124] Specifically, the isolation circuit 1 receives the first PWM signal and outputs the second PWM signal. The collector of the triode Q1 in the control circuit 2 is connected to the gate of the MOS transistor M1 in the drive circuit 3, and the emitter of the triode Q1 is grounded. When the second PWM signal is a high-level signal, the triode Q1 conducts, pulling the level at the gate of the MOS transistor M1 down to a low level, and then the MOS transistor M1 turns off. Therefore, at this time, the third PWM signal output by the drive circuit 3 is a low-level signal; similarly, when the second PWM signal is a low-level signal, the triode Q1 turns off, the gate level of the MOS transistor M1 is a high level, the MOS transistor M1 conducts, and at this time, the third PWM signal output by the drive circuit 3 is a high-level signal.

[0125] Further, please continue to refer to Figure 3 , any one of the first sensing circuit 4 and the second sensing circuit 5 includes a first resistor and a second resistor; wherein,

[0126] The first end of the first resistor constitutes the input end of the sensing circuit, and the second end of the first resistor and the first end of the second resistor are connected together to form the output end of the sensing circuit;

[0127] The second end of the second resistor is grounded.

[0128] For example, for the first sensing circuit 4, it includes a first resistor R41 and a second resistor R42; wherein,

[0129] The first end of the first resistor R41 forms the input end of the first sensing circuit 4, and the second end of the first resistor R41 and the first end of the second resistor R42 are connected to form the output end of the first sensing circuit 4;

[0130] The second end of the second resistor R42 is grounded.

[0131] For another example, for the second sensing circuit 5, it includes a first resistor R51 and a second resistor R52; wherein,

[0132] The first end of the first resistor R51 forms the input end of the second sensing circuit 5, and the second end of the first resistor R51 and the first end of the second resistor R52 are connected to form the output end of the second sensing circuit 5;

[0133] The second end of the second resistor R52 is grounded.

[0134] In this application, for the first sensing circuit 4, it senses the driving signal output by the control circuit 2 through the voltage division of the first resistor R41 and the second resistor R42; for the second sensing circuit 5, it senses the driving signal output by the control circuit 2 through the voltage division of the first resistor R51 and the second resistor R52.

[0135] It should be noted that, please refer to Figure 3 and Figure 4 simultaneously. In Figure 3 , the output end of the isolation circuit 1, the output end of the first sensing circuit 4, and the output end of the second sensing circuit 5 are connected to the counter interface end of the controller 6. The controller 6 can determine the number of pulses contained in each signal, and then judge the status information of each signal according to the number of pulses. Further, in Figure 4 , the output end of the isolation circuit 1, the output end of the first sensing circuit 4, and the output end of the second sensing circuit 5 are also connected to the analog-to-digital conversion interface in the controller 6. The controller 6 can perform analog-to-digital conversion on each signal to obtain the voltage value corresponding to each signal, and then use the voltage value corresponding to each signal to determine the health status and health level of the circuit module corresponding to the signal.

[0136] For the specific determination methods of the status information, health status and health level, please refer to the previous introduction, which will not be elaborated here.

[0137] The above are only the preferred embodiments of the present application, and are not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A PWM drive circuit, characterized in that: The PWM driving circuit includes an isolation circuit, a control circuit, a driving circuit, a first sensing circuit, a second sensing circuit and a controller; wherein, The input end of the isolation circuit is used to receive the first PWM signal from the controller; the output end of the isolation circuit is connected to the input end of the control circuit and the controller respectively; the isolation circuit is used to achieve electrical isolation, convert the first PWM signal into a second PWM signal and output it to the control circuit and the controller; The power supply end of the control circuit is connected to a DC driving voltage source; the output end of the control circuit is connected to the input end of the driving circuit and the input end of the first sensing circuit; the control circuit is used to generate a driving signal for driving the driving circuit according to the second PWM signal; The power supply end of the driving circuit is connected to the DC driving voltage source, and the output end of the driving circuit is respectively connected to the load to be driven and the input end of the second sensing circuit; the driving circuit is used to generate a third PWM signal for driving the load under the control of the driving signal; The output ends of the first sensing circuit and the second sensing circuit are respectively connected to the controller; wherein the first sensing circuit is used to sense the driving signal generated by the control circuit, and feed back the sensed first sensing signal to the controller; the second sensing circuit is used to sense the third PWM signal generated by the driving circuit, and feed back the sensed second sensing signal to the controller; The controller is used to determine whether the PWM drive circuit has an abnormality and a location where the abnormality occurs according to the first PWM signal, the second PWM signal, the first sensing signal and the second sensing signal; The controller is specifically used for: For any one of the second PWM signal, the first sensing signal and the second sensing signal, judging whether the signal is abnormal according to the number of pulses included in the signal and the number of pulses included in the first PWM signal, and obtaining status information indicating whether the signal is abnormal; determining whether the PWM drive circuit has an abnormality and a location where the abnormality occurs according to the state information of the second PWM signal, the state information of the first sensing signal, and the state information of the second sensing signal; The controller is specifically used for: When the state information of the second PWM signal is abnormal, determining that the PWM drive circuit has an abnormality, and determining that the location where the abnormality occurs is the isolation circuit; When the state information of the second PWM signal is normal and the state information of the first sensing signal is abnormal, determining that the PWM drive circuit has an abnormality, and determining that the location where the abnormality occurs is the control circuit; When the state information of the second PWM signal is normal, the state information of the first sensing signal is normal, and the state information of the second sensing signal is abnormal, it is determined that an abnormality exists in the PWM drive circuit, and the location where the abnormality occurs is determined to be the drive circuit.

2. The PWM driving circuit according to claim 1, characterized in that: The circuit also includes a load current acquisition circuit; wherein, The load current acquisition circuit is used to acquire the current of the load and feed back the acquired current value to the controller; The controller is further used to determine whether the load is abnormal according to the current value.

3. The PWM driving circuit according to claim 1, characterized in that: The controller is further configured to: When it is determined that there is no abnormality in the PWM drive circuit according to the state information of the second PWM signal, the state information of the first sensing signal, and the state information of the second sensing signal, for any one of the second PWM signal, the first sensing signal, and the second sensing signal, obtaining a voltage value corresponding to the signal; Determine the health status of the circuit module corresponding to the signal according to the voltage value corresponding to the signal and the preset voltage range corresponding to the signal; wherein the health status is used to indicate whether the circuit module is abnormal; The health status of each circuit module is displayed to the user so that the user can understand the health status of each circuit module.

4. The PWM driving circuit according to claim 3, characterized in that: The controller is further specifically used for: For any one of the second PWM signal, the first sensing signal and the second sensing signal, calculating a difference between a voltage value corresponding to the signal and a standard voltage value corresponding to the signal; Determine the health level of the circuit module corresponding to the signal according to the difference value and the corresponding relationship between the preset difference value and the health level; Display the health level of each circuit module to the user.

5. The driving circuit according to claim 1, characterized in that: The driving circuit includes a MOS tube and a voltage regulator diode; wherein, The gate of the MOS tube constitutes the input end of the driving circuit and is connected to the output end of the control circuit; The source electrode of the MOS tube constitutes the power supply terminal of the driving circuit and is connected to the DC driving voltage source; The drain of the MOS tube is connected to the anode of the voltage stabilizing diode, and the cathode of the voltage stabilizing diode is grounded.

6. The driving circuit according to claim 1, characterized in that: Any one of the first sensing circuit and the second sensing circuit comprises a first resistor and a second resistor; wherein, The first end of the first resistor constitutes an input end of the sensing circuit, and the second end of the first resistor and the first end of the second resistor are connected to constitute an output end of the sensing circuit; A second terminal of the second resistor is grounded.

7. The PWM driving circuit according to claim 1, characterized in that: The isolation circuit is an isolation circuit formed by a pulse transformer.

8. The PWM driving circuit according to claim 1, characterized in that: The control circuit includes a transistor and a third resistor; wherein, The base of the transistor constitutes the input end of the control circuit and is connected to the output end of the isolation circuit; The first end of the third resistor constitutes the power supply end of the control circuit and is connected to the DC driving voltage source; The second end of the third resistor is connected to the collector of the transistor to form the output end of the control circuit; The emitter of the transistor is grounded.

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