PWM (Pulse Width Modulation) driving circuit

Abstract

The invention provides a PWM (Pulse Width Modulation) driving circuit. According to the PWM driving circuit provided by the invention, through the arrangement of the first sensing circuit and the second sensing circuit, the driving signal output by the control circuit can be sensed through the first sensing circuit, the first sensing signal is generated and sent to the controller, and the third PWM signal output by the driving circuit is sensed through the second sensing circuit; according to the PWM driving circuit with the abnormality detection function, the PWM driving circuit generates a second sensing signal and sends the second sensing signal to the controller, and the controller can determine whether the PWM driving circuit is abnormal or not and determine the position of the abnormality according to the second PWM signal, the first sensing signal, the second sensing signal and the first PWM signal output to the PWM driving circuit by itself, so that the PWM driving circuit with the abnormality detection function can be provided, and the PWM driving circuit can be used for detecting the abnormality of the PWM driving circuit. Whether the PWM signal is abnormal or not can be accurately identified, the abnormal position can be quickly positioned, and the reliability and the safety of the circuit are improved.

Description

Technical Field

[0001] The present application relates to the technical field of electronic appliances, and in particular to a PWM drive circuit. Background Art

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

[0003] 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 power conversion, audio signal synthesis, communication system and robot control.

[0004] At present, there are still some technical defects in PWM drive circuits. 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, the present application provides a PWM drive circuit, which has an abnormality detection function, which can detect whether there is an abnormality in the PWM drive circuit and quickly locate the position where the abnormality occurs when there is an abnormality in the PWM drive circuit.

[0006] Specifically, the present application is implemented through the following technical solutions: The present application provides a PWM driving circuit, which 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 there is an abnormality in the PWM drive 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.

[0007] The PWM drive circuit provided in the present application can form a PWM drive circuit by setting an isolation circuit, a control circuit and a drive circuit, and electrical isolation can be achieved by setting an isolation circuit. Furthermore, by connecting the output end of the isolation circuit to a controller, and further setting a first sensing circuit and a second sensing circuit, the drive signal output by the control circuit can be sensed by the first sensing circuit to generate a first sensing signal and send it 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 send it to the controller. In this way, 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 the controller 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 abnormal location, and improve the reliability and safety of the circuit.

[0008] Furthermore, the PWM drive circuit provided in the present application, by setting up a load current acquisition circuit, can use the load current acquisition circuit to collect the current of the load, and feed back the collected current value to the controller, and the controller can determine whether the load is abnormal based on the detected current value. In this way, the working state of the load can be further detected, which can significantly improve the reliability and safety of the PWM drive circuit, prevent load overload and failure, and realize preventive maintenance and intelligent control.

[0009] Furthermore, the PWM drive circuit provided by the present application, 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, 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 according to the voltage value corresponding to the signal and the preset voltage range corresponding to the signal, determining the health state of the circuit module corresponding to the signal, and then displaying 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, the health state of the corresponding circuit module can be accurately determined based on the voltage value corresponding to each signal, which can not only improve the accuracy of abnormality detection, but also provide the health state of each circuit module to the user, so that the user can intuitively understand the working condition of the circuit, and promote preventive maintenance and optimized management.

[0010] Furthermore, the PWM driving circuit provided in the present application, for any one of the second PWM signal, the first perception signal and the second perception signal, calculates the difference between the voltage value corresponding to the signal and the standard voltage value corresponding to the signal, and determines the health level of the circuit module corresponding to the signal based on the difference value and the correspondence between the preset difference value and the health level, and then displays the health level of each circuit module to the user. In this way, the health level 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 modules can be replaced in time, which can improve the reliability and safety of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 A schematic diagram of a first embodiment of a PWM drive circuit provided in the present application; Figure 2 A schematic diagram of a second embodiment of a PWM drive circuit provided in the present application; Figure 3 A circuit diagram of a PWM drive circuit shown as an exemplary embodiment of the present application; Figure 4 A circuit diagram of a PWM drive circuit is provided for another exemplary embodiment of the present application.

[0012] Description of reference numerals: 1: Isolation circuit; 2: Control circuit; 3: Driving circuit; 4: First perception circuit; 5: Second perception circuit; 6: Controller; 7: Load current acquisition circuit; Q1: transistor; M1: MOS tube; D1: voltage zener diode; R41: the first resistor in the first sensing circuit; R42: the second resistor in the first sensing circuit; R51: the first resistor in the second sensing circuit; R52: the second resistor in the second sensing circuit; R3: The third resistor. DETAILED DESCRIPTION

[0013] Here, exemplary embodiments will be described in detail, and examples thereof are shown in the accompanying 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 implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application.

[0014] The terms used in this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The singular forms of "a", "said" and "the" used in this application are also intended to include plural forms, unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used in this article refers to and includes any or all possible combinations of one or more associated listed items.

[0015] It should be understood that although the terms first, second, third, etc. may be used in the present application to describe various information, these 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 "at the time of" or "when" or "in response to determining".

[0016] Specific embodiments are given below to introduce the technical solution of the present application in detail.

[0017] Figure 1 This is a schematic diagram of the first embodiment of the PWM drive 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; wherein, 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 connected to the input end of the control circuit 2 and the controller 6 respectively; the isolation circuit 1 is used to achieve electrical isolation, convert the first PWM signal into a second PWM signal and output it to the control circuit 2 and the controller 6; 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; 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; The output ends of the first sensing circuit 4 and the second sensing circuit 5 are respectively connected to the controller 6; wherein the first sensing circuit 4 is used to sense the driving signal generated by the control circuit 2, and feed back the sensed first sensing signal 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 back the sensed second sensing signal to the controller 6; The controller 6 is used to determine whether there is an abnormality in the PWM drive 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.

[0018] Specifically, the isolation circuit 1 is a circuit used to prevent current from being directly conducted between two circuits, but allows signals and energy to be transmitted in a certain way. In the present application, the isolation circuit 1 can separate the high-voltage or high-power circuit from the low-voltage or low-power control circuit, protect the control circuit 2 from high-voltage impact or noise interference, and reduce the influence of external electromagnetic interference on the PWM signal during the PWM signal transmission process.

[0019] Furthermore, the isolation circuit 1 may be an isolation circuit formed by an optical coupler, an isolation circuit formed by a magnetic coupler, etc. Optionally, in a possible implementation, the isolation circuit 1 is an isolation circuit formed by a pulse transformer.

[0020] Specifically, when the isolation circuit 1 is an isolation circuit composed of a pulse transformer, it isolates the signal through magnetic induction, converts the input first PWM signal into a magnetic signal and transmits it to the secondary, and converts it back into an electrical signal again at the secondary, thereby achieving electrical isolation between the input first PWM signal and the output second PWM signal, ensuring that there is no direct electrical connection between the two, preventing high voltage or noise from being transmitted from the input side to the load side, thereby protecting the circuit and controller 6.

[0021] For details, please continue to refer to Figure 1 , the power supply end of the control circuit 2 is connected to the DC driving voltage source, and the DC driving voltage source is used to provide the necessary working voltage to the control circuit 2. Further, the control circuit 2 is arranged between the isolation circuit 1 and the driving circuit 3, and the control circuit 2 is used to generate a driving signal according to the second PWM signal, and then transmit the driving signal to the driving circuit 3, so as to drive the above-mentioned driving circuit 3 with the driving signal. In addition, the output end of the control circuit 2 is also connected to the input end 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.

[0022] Optionally, in a possible implementation, the control circuit 2 may be a circuit composed of triodes, which is not limited in this embodiment.

[0023] It should be noted that the specific voltage value of the DC driving voltage source is set according to actual needs and is not limited in this embodiment.

[0024] For details, please continue to refer to Figure 1 The power supply end of the driving circuit 3 is connected to the DC driving voltage source, and the DC driving voltage source provides the necessary working circuit for the driving circuit 3. Further, the input end of the driving circuit 3 is connected to the control circuit 2, and the output end of the driving circuit 3 is connected to the load to be driven. The driving circuit 3 is used to receive the driving signal generated by the control circuit 2 and generate a third PWM signal under the control of the driving signal. The third PWM signal is further transmitted to the load to be driven to drive the load to work.

[0025] It should be noted that the load to be driven is set according to actual needs and is not limited in this embodiment. For example, in a possible implementation, the load to be driven is a motor.

[0026] In addition, the output end of the driving circuit 3 is also connected to the input end of the second sensing circuit 5, so as to send the third PWM signal to the second sensing circuit 5 for monitoring or feedback.

[0027] For details, please continue to refer to Figure 1The input end of the first sensing circuit 4 is connected to the output end of the control circuit 2, and the output end of the first sensing circuit 4 is connected to the controller 6; the first sensing circuit 4 is mainly used to sense the driving signal generated by the control circuit 2, and then feed back the sensed first sensing signal to the controller 6.

[0028] Furthermore, the input end of the second sensing circuit 5 is connected to the output end of the driving circuit 3, and the output end of the second sensing circuit 5 is connected to the controller 6; the second sensing circuit 5 is mainly used to sense the third PWM signal generated by the driving circuit 3, and feed back the sensed second sensing signal to the controller 6.

[0029] Optionally, in a possible implementation, the first sensing circuit 4 and the second sensing circuit 5 may be voltage divider circuits, which are not limited in this embodiment.

[0030] For details, please continue to refer to Figure 1 The controller 6 is respectively connected to 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. 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 based on the second PWM signal, the first sensing signal, and the second sensing signal.

[0031] In specific implementation, for example, the controller 6 can determine whether the isolation circuit 1 is abnormal based on whether the second PWM signal is abnormal. When the second PWM signal is abnormal, the isolation circuit 1 is determined to be abnormal, otherwise the isolation circuit 1 is determined to be normal. Similarly, the controller 6 can determine whether the control circuit 2 is abnormal based on the first sensing signal. When the first sensing signal is abnormal, the control circuit 2 is determined to be abnormal, otherwise the control circuit 2 is determined to be normal. Similarly, the controller 6 can also determine whether the drive circuit 3 is abnormal based on the second sensing signal. When the second sensing signal is abnormal, the drive circuit 3 is determined to be abnormal, otherwise the drive circuit 3 is determined to be normal.

[0032] Specifically, for example, in a possible implementation, after the controller 6 sends out the first PWM signal, the controller 6 cannot detect subsequent signals, thereby determining that the location where the abnormality occurs is the isolation circuit 1 .

[0033] For another example, in another embodiment, after the controller 6 sends out the first PWM signal, the controller 6 only detects the second PWM signal but does not detect the first sensing signal and the second sensing signal, thereby determining that the location where the abnormality occurs is the control circuit 2.

[0034] For another example, after the controller 6 sends out the first PWM signal, the controller 6 detects the second PWM signal and the first sensing signal, but does not detect the second sensing signal, thereby determining that the location where the abnormality occurs is the drive circuit 3.

[0035] Optionally, in a possible implementation, the controller 6 is specifically configured to: 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; Whether there is an abnormality in the PWM drive circuit and the location where the abnormality occurs are determined 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.

[0036] It should be noted that the input and output of the PWM drive circuit are both PWM signals. Under normal conditions, that is, when there is no abnormality in the PWM drive circuit, the number of pulses contained in the first PWM signal issued by the controller 6, the number of pulses contained in the second PWM signal output by the isolation circuit 1, the number of pulses contained in the drive signal generated by the control circuit 2, and the number of pulses contained in the third PWM signal generated by the drive circuit 3 should be equal, and the number of pulses contained in the first sensing signal sensed by the first sensing circuit 4 and the number of second pulses sensed by the second sensing circuit 5 should also be equal to the number of pulses contained in the first PWM signal. Therefore, for any one of the second PWM signal, the first sensing signal, and the second sensing signal, it can be determined whether the signal is abnormal based on the number of pulses contained in the signal and the number of pulses contained in the first PWM signal, and the state information characterizing whether the signal is abnormal is obtained. For example, when the number of pulses contained in the signal is equal to the number of pulses contained in the first PWM signal, the state information of the signal is determined to be normal, and when the number of pulses contained in the signal is not equal to the number of pulses contained in the first PWM signal, the state information of the signal is determined to be abnormal.

[0037] Combined with the above introduction, for example, in a possible implementation, the controller 6 sends out a first PWM signal, the number of pulses contained in the first PWM signal is 100, the isolation circuit 1 receives the first PWM signal and sends out a second PWM signal, the control circuit 2 receives the second PWM signal and sends out a drive signal, the first sensing circuit 4 senses the drive signal and generates a first sense 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 sense signal. At this time, the controller 6 detects that the number of pulses contained in the second PWM signal is 100, the number of pulses contained in the first sense signal is 90, and the number of pulses contained in the second sense signal is 90. At this time, it means that the first sense signal and the second sense signal are abnormal, and the status information of the first sense signal and the second sense signal is abnormal.

[0038] For another example, in another possible implementation, the controller 6 sends out a first PWM signal, the number of pulses contained in the first PWM signal is 100, the isolation circuit 1 receives the first PWM signal and sends out a second PWM signal, the control circuit 2 receives the second PWM signal and sends out a drive signal, the first sensing circuit 4 senses the drive signal and generates a first sense 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 sense signal. At this time, the controller 6 detects that the number of pulses contained in the second PWM signal is 100, the number of pulses contained in the first sense signal is 90, and the number of pulses contained in the second sense signal is 80. At this time, it means that the first sense signal and the second sense signal are abnormal, and the status information of the first sense signal and the second sense signal is abnormal.

[0039] 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.

[0040] Please continue to refer to Figure 1 Optionally, in a possible implementation, 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 includes: (1) When the state information of the second PWM signal is abnormal, it is determined that the PWM drive circuit has an abnormality, and the location where the abnormality occurs is determined to be the isolation circuit.

[0041] Specifically, in combination with the above introduction, when the controller 6 cannot 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 determines that the location where the abnormality occurs is the isolation circuit 1.

[0042] (2) When the state information of the second PWM signal is normal and the state information of the first sensing signal is abnormal, it is determined that the PWM drive circuit has an abnormality, and the location where the abnormality occurs is determined to be the control circuit.

[0043] Specifically, combined with the above introduction, for example, the controller 6 sends a first PWM signal, the number of pulses contained in the first PWM signal is 100, the number of pulses contained in the first perception signal detected by the controller 6 is 90, and the number of pulses contained in the second perception signal is 90. At this time, it is indicated that the first perception signal and the second perception signal are abnormal, and the state information of the first perception signal and the second perception signal is abnormal. Since the number of pulses contained in the second perception signal is equal to the number of pulses contained in the first perception signal, it is determined that the abnormality of the second perception signal is caused by the abnormality of the first perception signal, and then the location where the abnormality occurs is determined to be the control circuit 2.

[0044] (3) 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 the PWM drive circuit has an abnormality, and the location where the abnormality occurs is determined to be the drive circuit 3.

[0045] Specifically, in combination with the above introduction, when the controller 6 cannot detect the second perception signal or the number of pulses contained in the detected second perception signal is not equal to the number of pulses contained in the first perception signal, it determines that the location where the abnormality occurs is the driving circuit 3.

[0046] 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, and electrical isolation can be achieved by setting an isolation circuit. Furthermore, by connecting the output end of the isolation circuit to the controller, and further setting a first sensing circuit and a second sensing circuit, the drive signal output by the control circuit can be sensed by the first sensing circuit to generate a first sensing signal and send it 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 send it to the controller. In this way, 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 the controller 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 abnormal location, and improve the reliability and safety of the circuit.

[0047] Figure 2This is a schematic diagram of the second embodiment of the PWM drive circuit provided by this application. Please refer to Figure 2 Based on the above embodiment, the PWM driving circuit provided in this embodiment further includes a load current acquisition circuit 7; wherein, The load current acquisition circuit 7 is used to acquire the current of the load and feed back the acquired current value to the controller 6 .

[0048] The controller 6 is further configured to determine whether the load is abnormal according to the current value.

[0049] 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.

[0050] It should be noted that the normal operating range of the load current is set according to actual needs and is not limited in this embodiment. For example, in one possible implementation, the normal operating range of the load current is 15-30A. If the controller 6 detects that the load current value is outside 15-30A, it is determined that the load is abnormal.

[0051] The PWM drive circuit provided in this embodiment is provided with a load current acquisition circuit. In this way, the load current acquisition circuit can be used to collect the current of the load, and the collected current value can be fed back to the controller. The controller can then determine whether the load is abnormal based on the detected current value. In this way, the working state of the load can be further detected, which can significantly improve the reliability and safety of the PWM drive circuit, prevent load overload and failure, and realize preventive maintenance and intelligent control.

[0052] Optionally, in a possible implementation, the controller 6 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.

[0053] Specifically, for any one of the second PWM signal, the first sensing signal and the second sensing signal, the controller 6 may perform analog-to-digital conversion on the signal to obtain a voltage value corresponding to the signal.

[0054] Further, 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 is not limited in this embodiment. In addition, the preset voltage ranges corresponding to the signals may be the same or different, and are not limited in this embodiment. For example, in one embodiment, the preset voltage ranges corresponding to the signals are shown in Table 1: Table 1 Signals and their corresponding preset voltage ranges

[0055] In specific implementation, for a certain signal, if the voltage value corresponding to the signal is within the preset voltage range corresponding to the signal, the health state of the circuit module corresponding to the signal is determined to be healthy, otherwise the health state of the circuit module corresponding to the signal is determined to be unhealthy.

[0056] For example, when the voltage value of the second PWM signal is outside the corresponding preset voltage range, the health state of the circuit module corresponding to the signal is determined to be unhealthy, that is, the health state of the isolation circuit 1 is unhealthy; similarly, when the voltage value of the first perception signal is outside the corresponding preset voltage range, the health state of the circuit module corresponding to the signal is determined to be abnormal, that is, the health state of the control circuit 2 is unhealthy; similarly, when the voltage value of the second perception signal is outside the corresponding preset voltage range, the health state of the circuit module corresponding to the signal is determined to be unhealthy, that is, the health state of the drive circuit 3 is unhealthy.

[0057] The PWM driving circuit provided in this embodiment, when it is determined that there is no abnormality in the PWM driving 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, 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 according to the voltage value corresponding to the signal and the preset voltage range corresponding to the signal, determining the health state of the circuit module corresponding to the signal, and then displaying 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, the health state of the corresponding circuit module can be accurately determined based on the voltage value corresponding to each signal, which can not only improve the accuracy of abnormality detection, but also provide the health state of each circuit module to the user, so that the user can intuitively understand the working condition of the circuit, and promote preventive maintenance and optimized management.

[0058] Optionally, in a possible implementation, based on the above embodiment, the controller 6 is further configured to: For any one of the second PWM signal, the first sensing signal and the second sensing signal, a difference value between a voltage value corresponding to the signal and a standard voltage value corresponding to the signal is calculated.

[0059] The health level of the circuit module corresponding to the signal is determined according to the difference value and the corresponding relationship between the preset difference value and the health level.

[0060] Display the health level of each circuit module to the user.

[0061] 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 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 between the voltage value corresponding to the signal and the standard voltage value corresponding to the signal. In this embodiment, it is not limited. The following is an example of using the absolute value of the difference between the actual voltage value and the standard voltage value relative to the standard voltage value as the percentage of the difference between the voltage value corresponding to the signal and the standard voltage value corresponding to the signal.

[0062] For example, in a possible implementation, when calculating the difference between the voltage value corresponding to the signal and the standard voltage value corresponding to the signal, the calculation may be performed according to the following formula: ; in, is the difference between the voltage value corresponding to the signal and the standard voltage value corresponding to the signal; U 1 is the voltage value corresponding to the signal; U 0 is the standard voltage value corresponding to the signal.

[0063] Further, for each signal, the correspondence between the preset difference value and the health level is set according to actual needs, and is not limited in this embodiment. In addition, for different signals, the correspondence between the preset difference value and the health level can be the same or different.

[0064] For example, in a possible implementation, for different signals, the correspondence between the preset difference value and the health level is the same. Table 2 is a correspondence between the preset difference value and the health level corresponding to each signal shown in an exemplary embodiment.

[0065] Table 2 Correspondence between the preset difference value and health level corresponding to each signal

[0066] Please refer to Table 2, combined with the example shown in Table 1, for example, in one possible implementation, after calculation, it is determined that the difference value corresponding to the second PWM signal is 3%. At this time, the health level of the isolation circuit 1 is determined to be excellent; for another example, after calculation, it is determined that the difference value corresponding to the first perception signal is 15%. At this time, the health level of the control circuit 2 is determined to be passing; for another example, it is determined that the difference value corresponding to the second perception signal is 21%. At this time, the health level of the drive circuit 3 is determined to be failing.

[0067] Furthermore, after determining the health level of each circuit module, the health level of each circuit module is displayed to the user, and the user can observe the health level of each circuit module. When the health level of the circuit module is lower than the usable health level set by the user, the user can replace the corresponding circuit module to increase the stability and safety of the circuit operation.

[0068] The PWM driving circuit provided in this embodiment, for any one of the second PWM signal, the first perception signal and the second perception signal, calculates the difference between the voltage value corresponding to the signal and the standard voltage value corresponding to the signal, and determines the health level of the circuit module corresponding to the signal according to the difference value and the correspondence between the preset difference value and the health level, and then displays the health level of each circuit module to the user. In this way, the health level 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 modules can be replaced in time, which can improve the reliability and safety of the system.

[0069] Figure 3 FIG. 1 is a circuit diagram of a PWM drive circuit according to an exemplary embodiment of the present application. Figure 4 This application provides another exemplary embodiment of the PWM drive circuit schematic diagram; please also refer to Figure 3 and Figure 4 On the basis of the above embodiments, the PWM driving circuit provided in this embodiment, the isolation circuit 1 is an isolation circuit 1 composed of a pulse transformer.

[0070] Further, optionally, the control circuit 2 includes a transistor Q1 and a third resistor R3; wherein, The base of the transistor Q1 constitutes the input end of the control circuit 2 and is connected to the output end of the isolation circuit 1; The first end of the third resistor R3 constitutes the power supply end of the control circuit 2 and is connected to the DC driving voltage source; The second end of the third resistor R3 is connected to the collector of the transistor Q1 to form the output end of the control circuit 2; The emitter of the transistor Q1 is grounded.

[0071] Optional, please continue to refer to Figure 3 , the PWM driving circuit provided in this embodiment, the driving circuit 3 includes a MOS tube M1 and a voltage regulator diode D1; wherein, The gate of the MOS tube M1 constitutes the input end of the driving circuit 3 and is connected to the output end of the control circuit 2; The source of the MOS tube M1 constitutes the power supply end of the driving circuit 3 and is connected to the DC driving voltage source; The drain of the MOS tube M1 is connected to the anode of the voltage stabilizing diode D1 , and the cathode of the voltage stabilizing diode D1 is grounded.

[0072] Please continue to refer to Figure 3 and Figure 4 , the following briefly introduces the working principle of the PWM drive circuit: Specifically, the isolation circuit 1 receives the first PWM signal and outputs the second PWM signal. The collector of the transistor Q1 in the control circuit 2 is connected to the gate of the MOS tube M1 in the drive circuit 3, and the emitter of the transistor Q1 is grounded. When the second PWM signal is a high-level signal, the transistor Q1 is turned on, and the level at the gate of the MOS tube M1 is pulled down to a low level, and then the MOS tube M1 is turned 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 transistor Q1 is turned off, the level at the gate of the MOS tube M1 is a high level, and the MOS tube M1 is turned on. At this time, the third PWM signal output by the drive circuit 3 is a low-level signal.

[0073] For further information, please refer to Figure 3 , any one of the first sensing circuit 4 and the second sensing circuit 5 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.

[0074] For example, the first sensing circuit 4 includes a first resistor R41 and a second resistor R42; wherein, The first end of the first resistor R41 constitutes 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 constitute the output end of the first sensing circuit 4; A second end of the second resistor R42 is grounded.

[0075] For another example, the second sensing circuit 5 includes a first resistor R51 and a second resistor R52; wherein, The first end of the first resistor R51 constitutes 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; A second end of the second resistor R52 is grounded.

[0076] In the present application, for the first sensing circuit 4, it senses the driving signal output by the control circuit 2 through the voltage dividing effect 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 dividing effect of the first resistor R51 and the second resistor R52.

[0077] Please also refer to Figure 3 and Figure 4 ,exist Figure 3 In the embodiment, 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 state information of each signal according to the number of pulses. Figure 4 In the figure, 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 a 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.

[0078] For the specific method of determining status information, health status and health level, please refer to the previous introduction and will not be repeated here.

[0079] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection 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 there is an abnormality in the PWM drive 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.

2. The PWM driving circuit according to claim 1, characterized in that: 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; Whether there is an abnormality in the PWM drive circuit and the location where the abnormality occurs are determined 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.

3. The PWM driving circuit according to claim 2, characterized in that: 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.

4. 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.

5. The PWM driving circuit according to claim 3, 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.

6. The PWM driving circuit according to claim 5, 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.

7. 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.

8. 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.

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

10. 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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