Driving protection circuit and electronic equipment

Abstract

The invention relates to a driving protection circuit. According to the driving protection circuit, the abnormal state of the direct-current voltage provided by the rectifier bridge circuit is detected through the driving circuit, the abnormal state of the driving current of the driving circuit can also be detected through the abnormal protection circuit, and abnormal protection signals and corresponding abnormal alarm signals are output through the abnormal protection circuit according to the two abnormal states. The driving circuit is turned off through the abnormal protection signal, the driving circuit is forbidden to continuously output the driving signal to the power module so as to realize dual protection on the power module, the protection actions are triggered by the circuit action consisting of the components, and the protection period only comprises the transmission process of the voltage signal and the logic judgment process of the components. The action cycle of the component is smaller than the self-calculation logic cycle of software, so that the power module can be protected in time, and the problem that an existing driving circuit is not protected in time is solved.

Description

Technical Field

[0001] The present application relates to the field of electronic information technology, and in particular to a driving protection circuit and an electronic device. Background Art

[0002] In the drive circuit, the power module (IPM) is a key component. Damage to the IPM requires replacing the mainboard, which increases manpower and material resources. With the advancement of technology and keeping pace with the times, a variety of protections have been implemented for the drive circuit. However, the existing protection judgment time includes the software's self-calculation logic cycle. This long self-calculation logic cycle prevents timely protection, resulting in damage to the power module. Summary of the Invention

[0003] The present application provides a driving protection circuit and an electronic device to solve the problem of untimely protection of existing driving circuits.

[0004] In a first aspect, the present application provides a driving protection circuit, the driving protection circuit comprising:

[0005] A rectifier bridge circuit is used to convert the input three-phase AC power into a DC voltage;

[0006] a drive circuit, wherein an input end of the drive circuit is connected to an output end of the rectifier bridge circuit, the drive circuit outputs a first abnormality detection signal according to an abnormal state of the DC voltage, and provides a drive signal to a power module when the first abnormality detection signal indicates a normal state, the power module being configured to drive a load according to the drive signal;

[0007] An abnormality protection circuit is connected to the drive circuit, and when receiving the first abnormality detection signal indicating an abnormal state, the abnormality protection circuit outputs an abnormality protection signal and a first abnormality alarm signal according to the first abnormality detection signal; it is also used to detect the drive current output by the drive circuit, and output an abnormality protection signal and a second abnormality alarm signal when determining an abnormal state based on the drive current, the first abnormality alarm signal and the second abnormality alarm signal indicating different abnormal types, and the abnormality protection signal is used to prohibit the drive circuit from outputting a drive signal.

[0008] Optionally, the abnormality protection circuit includes:

[0009] a first protection subcircuit, the first protection subcircuit being connected to the drive circuit and configured to detect a drive current of the drive circuit, output a second abnormality detection signal according to an abnormal state of the drive current, and output a second abnormality alarm signal when an abnormal state is determined according to the drive current;

[0010] The second protection subcircuit is connected to the driving circuit and the first protection subcircuit respectively, and is used to output the abnormal protection signal when at least one of the first abnormality detection signal and the second abnormality detection signal indicates an abnormal state.

[0011] Optionally, the first protection sub-circuit includes:

[0012] an acquisition circuit, connected to the drive circuit, and configured to convert the drive current of the drive circuit into a drive voltage;

[0013] a voltage comparison circuit, wherein an input end of the voltage comparison circuit is connected to an output end of the acquisition circuit, and is configured to output a low-level voltage detection signal when the driving voltage is less than or equal to a voltage threshold, or output a high-level voltage detection signal when the driving voltage is greater than the voltage threshold;

[0014] a first protection branch, wherein an input end of the first protection branch is connected to an output end of the voltage comparison circuit, and is configured to output a corresponding second abnormality detection signal according to a level state of the voltage detection signal;

[0015] The second protection branch has an input end connected to the output end of the voltage comparison circuit, and is used to output the second abnormal alarm signal when the level state of the voltage detection signal is high.

[0016] Optionally, the acquisition circuit includes a first resistor and a second resistor connected in parallel, the first end of the first resistor and the first end of the second resistor are respectively connected to the driving circuit and the voltage comparison circuit, and the second end of the first resistor and the second end of the second resistor are commonly grounded.

[0017] Optionally, the voltage comparison circuit includes a voltage comparator, a third resistor, a fourth resistor, a rollover timer, and a first capacitor, wherein the negative input terminal of the voltage comparator is respectively connected to the first end of the first resistor and the driving circuit, the positive input terminal of the voltage comparator is respectively connected to the second end of the third resistor and the first end of the fourth resistor, the first capacitor is connected between the first end of the third resistor and the second end of the fourth resistor, and the output terminal of the voltage comparator is connected to the rollover timer;

[0018] The voltage comparator is used to output a corresponding voltage comparison signal based on the comparison result of the driving current and the voltage threshold, and the flip timer is used to flip the level state of the voltage comparison signal and output it as a voltage detection signal after receiving the preset duration of the voltage comparison signal, wherein the third resistor and the fourth resistor are used to set the voltage threshold.

[0019] Optionally, the first protection branch includes a first current limiting resistor, a first pull-down resistor, a first pull-up resistor, a second pull-up resistor, a second capacitor, a first transistor and a second transistor, the first end of the first current limiting resistor is respectively connected to the output end of the flip timer and the second protection branch, the second end of the first current limiting resistor is respectively connected to the first end of the first pull-down resistor and the base of the second transistor, the collector of the second transistor is respectively connected to the base of the first transistor and the first end of the first pull-up resistor, the emitter of the second transistor and the second end of the second capacitor and the emitter of the first transistor are commonly grounded, the second end of the first pull-up resistor is connected to the first end of the second capacitor and the first end of the second pull-up resistor, and the node where the collector of the first transistor is connected to the second end of the second pull-up resistor is used to output the second abnormality detection signal.

[0020] Optionally, the second protection branch includes a third pull-up resistor, a fourth pull-up resistor, a second pull-down resistor, a second current limiting resistor, a third capacitor and a third transistor, the first end of the third pull-up resistor is respectively connected to the output end of the flip timer and the first end of the first current limiting resistor, the second end of the third pull-up resistor is respectively connected to the base of the third transistor and the first end of the second pull-down resistor, the collector of the third transistor is respectively connected to the first end of the fourth pull-up resistor and the first end of the second current limiting resistor, the emitter of the third transistor is commonly grounded with the second end of the second pull-down resistor and the second end of the third capacitor, and the node where the second end of the second current limiting resistor is connected to the first end of the third capacitor is used to output the second abnormal alarm signal when an abnormal state is determined based on the driving current.

[0021] Optionally, the second protection subcircuit includes a fourth transistor, an inverter, a third pull-down resistor and an OR gate, the base of the fourth transistor is respectively connected to the input end of the inverter and the drive circuit, the collector of the fourth transistor is grounded via the third pull-down resistor, and the collector of the fourth transistor is also used to output a first alarm signal corresponding to the first abnormal protection signal when the fourth transistor is turned on, the output end of the inverter is connected to the first input end of the OR gate, the second input end of the OR gate is connected to the collector of the first transistor, and the output end of the OR gate is used to output the abnormal protection signal.

[0022] Optionally, the drive circuit includes a three-phase inverter bridge circuit, each phase inverter bridge circuit includes two drive sub-circuits, each of the drive sub-circuits includes a drive chip and a drive pull-up resistor, a first drive pull-down resistor, a second drive pull-down resistor, a third current limiting resistor, a fourth current limiting resistor, a first filter capacitor, a second filter capacitor, a third filter capacitor, a drive transistor and a drive diode, the first power pin of the drive chip is connected to an external power supply, the second power pin of the drive chip is respectively connected to the first end of the drive pull-up resistor and the first end of the first filter capacitor, the second end of the drive pull-up resistor is connected to the fault pin of the drive chip, and the drive The positive input end of the chip is connected to the third current limiting resistor and the second filter capacitor, the negative input end of the driver chip is respectively connected to the fourth current limiting resistor and the third filter capacitor, the enable pin of the driver chip is connected to the base of the driver transistor, the voltage output pin of the driver chip is respectively connected to the emitter of the driver transistor and the positive electrode of the driver diode, the negative electrode of the driver diode is connected to the collector of the driver transistor, the fault pin of the driver chip is used to output a first abnormality detection signal according to the abnormal state of the DC voltage, and the driver chip stops outputting the drive signal when receiving the abnormal protection signal at the negative input end.

[0023] In a second aspect, the present application provides an electronic device, comprising an electrically connected power module and a driving protection circuit as described in any one of the above items.

[0024] The above-mentioned technical solution provided by the embodiment of the present application has the following advantages over the prior art: the drive protection circuit provided by the embodiment of the present application includes a rectifier bridge circuit, which is used to convert the connected three-phase AC power supply into a DC voltage; a drive circuit, the input end of the drive circuit is connected to the output end of the rectifier bridge circuit, the drive circuit outputs a first abnormality detection signal according to the abnormal state of the DC voltage, and provides a drive signal to the power module when the first abnormality detection signal indicates a normal state, and the power module is used to drive the load according to the drive signal; an abnormality protection circuit, the abnormality protection circuit is connected to the drive circuit, and when receiving the first abnormality detection signal indicating an abnormal state, outputs an abnormality protection signal and a first abnormality alarm signal according to the first abnormality detection signal; it is also used to detect the drive current output by the drive circuit, and output an abnormality protection signal and a second abnormality alarm signal when determining an abnormal state based on the drive current, the first abnormality alarm signal and the second abnormality alarm signal indicate different abnormality types, and the abnormality protection signal is used to prohibit the drive circuit from outputting the drive signal.

[0025] Based on the above-mentioned drive protection circuit, not only can the abnormal state of the DC voltage provided by the rectifier bridge circuit be detected by the drive circuit, but the abnormal state of the driving current of the drive circuit can also be detected by the abnormal protection circuit, and the abnormal protection circuit outputs an abnormal protection signal and a corresponding abnormal alarm signal for the above two abnormal states. The drive circuit is shut down by the abnormal protection signal, and the drive circuit is prohibited from continuing to output the drive signal to the power module, so as to achieve double protection for the power module. Moreover, the above-mentioned protection actions are all triggered by the circuit actions composed of components. The protection cycle only includes the transmission process of the voltage signal and the logical judgment process of the components. The action cycle of the components is shorter than the self-calculated logic cycle of the software. Therefore, timely protection can be achieved for the power module, solving the problem of untimely protection of the existing drive circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0028] One or more embodiments are exemplarily illustrated by pictures in the corresponding drawings. These exemplifications do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings are represented as similar elements. Unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0029] Figure 1 A schematic diagram of the structure of a drive protection circuit provided in an embodiment of the present application;

[0030] Figure 2 A schematic diagram of the structure of a drive protection circuit provided in an embodiment of the present application;

[0031] Figure 3 A schematic diagram of the structure of a drive protection circuit provided in an embodiment of the present application;

[0032] Figure 4 A schematic diagram of the structure of a drive protection circuit provided in an embodiment of the present application;

[0033] Figure 5 A schematic diagram of the structure of a driving sub-circuit provided in an embodiment of the present application. DETAILED DESCRIPTION

[0034] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0035] The disclosure below provides many different embodiments or examples for implementing different configurations of the present invention. To simplify the disclosure of the present invention, the components and configurations of specific examples are described below. Of course, these are merely examples and are not intended to limit the present invention. In addition, the present invention may repeat reference numerals and / or letters in different examples. Such repetition is for the purpose of simplicity and clarity and does not in itself indicate the relationship between the various embodiments and / or configurations discussed.

[0036] Figure 1 FIG. 1 is a schematic diagram of a driving protection circuit in an embodiment. Figure 1 , the drive protection circuit includes:

[0037] The rectifier bridge circuit 110 is used to convert the input three-phase AC power into a DC voltage;

[0038] a drive circuit 120, wherein an input end of the drive circuit 120 is connected to an output end of the rectifier bridge circuit 110, the drive circuit 120 outputs a first abnormality detection signal according to an abnormal state of the DC voltage, and provides a drive signal to the power module 200 when the first abnormality detection signal indicates a normal state, and the power module 200 is configured to drive a load according to the drive signal;

[0039] The abnormality protection circuit 130 is connected to the drive circuit 120. When receiving the first abnormality detection signal indicating an abnormal state, the abnormality protection circuit 130 outputs an abnormality protection signal and a first abnormality alarm signal according to the first abnormality detection signal; it is also used to detect the driving current output by the drive circuit 120, and output an abnormality protection signal and a second abnormality alarm signal when determining an abnormal state based on the driving current. The first abnormality alarm signal and the second abnormality alarm signal indicate different abnormality types, and the abnormality protection signal is used to prohibit the drive circuit 120 from outputting a driving signal.

[0040] Specifically, the rectifier bridge circuit 110 includes a three-phase rectifier bridge, which is composed of six diodes and two rectifier capacitors. Each rectifier bridge includes two diodes connected in series, and each rectifier bridge is connected in parallel with the other two rectifier bridges. One rectifier bridge is connected to one phase of the three-phase AC power supply. Two rectifier capacitors are connected in series and then connected in parallel with each rectifier bridge. The rectifier bridge circuit 110 is used to convert the three-phase AC power supply into a DC voltage and provide it to the drive circuit 120.

[0041] The driving circuit 120 is used to detect the abnormal state of the DC voltage to detect whether there is an overvoltage abnormality or an overcurrent abnormality in the driving circuit 120, and output a first abnormality detection signal to the abnormality protection circuit 130 based on the detection result. The first abnormality detection signal is the signal detected by the driving circuit 120 itself. When the first abnormality detection signal indicates a normal state, the driving circuit 120 normally provides a driving signal to the subsequent power module 200, and the power module 200 normally drives the load based on the driving signal.

[0042] The abnormal protection circuit 130 will receive the first abnormal detection signal provided by the driving circuit 120. The first abnormal detection signal is recorded as the FLT signal. If the first abnormal detection signal indicates an abnormal state, the abnormal protection circuit 130 will output an abnormal protection signal and a first abnormal alarm signal. The first abnormal alarm signal is used to remind the user that there is an overcurrent or overvoltage abnormality in the driving circuit 120, and the abnormal protection signal is used to control the driving circuit 120 to stop sending the driving signal to avoid the overvoltage and overcurrent conditions from causing burning effects on the subsequent power module 200. The first abnormal alarm signal is recorded as FLT_DSP.

[0043] The abnormal protection circuit 130 can also detect the abnormal state of the driving current output by the driving circuit 120 to detect whether there is an overcurrent abnormality in the driving current output by the driving circuit 120, and output an abnormal protection signal and a second abnormal alarm signal when the abnormal state is determined based on the driving current. The second abnormal alarm signal is recorded as FO_DSP. The second abnormal alarm signal is used to remind the user that there is an overcurrent abnormality in the driving current output by the driving circuit 120, which will cause overcurrent impact on the subsequent power module 200. The driving circuit 120 is shut down by the abnormal protection signal to prohibit the driving circuit 120 from continuing to send a driving signal to the subsequent power module 200 to achieve overcurrent protection for the power module 200.

[0044] That is, the drive protection circuit can not only detect the abnormal state of the DC voltage provided by the rectifier bridge circuit 110 through the drive circuit 120, but also detect the abnormal state of the driving current of the drive circuit 120 through the abnormal protection circuit 130, and output the abnormal protection signal and the corresponding abnormal alarm signal for the above two abnormal states through the abnormal protection circuit 130, and shut down the drive circuit 120 through the abnormal protection signal, prohibiting the drive circuit 120 from continuing to output the drive signal to the power module 200, so as to achieve double protection for the power module 200, and the above protection actions are all triggered by the circuit action composed of components, and the protection cycle only includes the transmission process of the voltage signal and the logical judgment process of the components. The action cycle of the components is less than the self-calculated logic cycle of the software, so that the power module 200 can achieve timely protection effect, solving the problem of untimely protection of the existing drive circuit 120.

[0045] In one embodiment, referring to Figure 2 , the abnormal protection circuit 130 includes:

[0046] a first protection subcircuit 131, connected to the drive circuit 120, configured to detect a drive current of the drive circuit 120, output a second abnormality detection signal based on an abnormal state of the drive current, and output a second abnormality alarm signal when an abnormal state is determined based on the drive current;

[0047] The second protection sub-circuit 132 is connected to the driving circuit 120 and the first protection sub-circuit 131 respectively, and is used to output the abnormal protection signal when at least one of the first abnormality detection signal and the second abnormality detection signal indicates an abnormal state.

[0048] Specifically, the first protection subcircuit 131 is configured to detect the drive current output by the drive circuit 120 and output a second abnormality detection signal based on the abnormal state of the drive current. Specifically, the level of the second abnormality detection signal is related to the abnormal state of the drive current. When the drive current is abnormal, the second abnormality detection signal is high, and when the drive current is normal, the second abnormality detection signal is low. The second abnormality detection signal is denoted as a TCBH signal. Similarly, the level of the first abnormality detection signal is related to the abnormal state of the DC voltage. When the DC voltage is abnormal, the first abnormality detection signal is low, and when the DC voltage is normal, the first abnormality detection signal is high.

[0049] The second protection subcircuit 132 outputs a protection signal based on the first abnormality detection signal and the second abnormality detection signal, specifically including: outputting a normal protection signal when both the first abnormality detection signal and the second abnormality detection signal indicate a normal state, and the normal protection signal is a low level; outputting an abnormal protection signal when at least one of the first abnormality detection signal and the second abnormality detection signal indicates an abnormal state, and the abnormal protection signal is a high level, and the protection signal is recorded as an IN- signal.

[0050] In one embodiment, referring to Figure 3 , the first protection sub-circuit 131 includes:

[0051] An acquisition circuit 1311, connected to the drive circuit 120, for converting the drive current of the drive circuit 120 into a drive voltage;

[0052] a voltage comparison circuit 1312, wherein an input end of the voltage comparison circuit 1312 is connected to an output end of the acquisition circuit 1311, and is configured to output a low-level voltage detection signal when the driving voltage is less than or equal to a voltage threshold, or output a high-level voltage detection signal when the driving voltage is greater than the voltage threshold;

[0053] a first protection branch 1313, wherein an input end of the first protection branch 1313 is connected to an output end of the voltage comparison circuit 1312, and is configured to output a corresponding second abnormality detection signal according to a level state of the voltage detection signal;

[0054] The second protection branch 1314 has an input end connected to the output end of the voltage comparison circuit 1312 and is configured to output the second abnormal alarm signal when the voltage detection signal is at a high level.

[0055] Specifically, the acquisition circuit 1311 is used to convert the driving current output by the driving circuit 120 into a driving voltage and then provide it to the voltage comparison circuit 1312. The voltage comparison circuit 1312 compares the driving voltage with the voltage threshold to determine whether the driving voltage is greater than the voltage threshold. If the driving voltage is greater than the voltage threshold, it indicates that the driving current has an overcurrent phenomenon, and a high-level voltage detection signal is output; if the driving voltage is less than the voltage threshold, it indicates that the driving current has not an overcurrent phenomenon, and a low-level voltage detection signal is output. By comparing the driving voltage and the voltage threshold, the abnormal state of the driving current is determined, and the corresponding voltage detection signal is output.

[0056] The first protection branch 1313 outputs a corresponding second abnormal detection signal according to the voltage detection signal. Specifically, when the voltage detection signal is at a high level, the high-level second abnormal detection signal is output to indicate an abnormal state; when the voltage detection signal is at a low level, the low-level second abnormal detection signal is output to indicate a normal state.

[0057] The second protection branch 1314 determines whether to output a second abnormal alarm signal based on the level state of the voltage detection signal. Specifically, the second abnormal alarm signal is output when the voltage detection signal is a high level indicating an overcurrent abnormality to remind the user that the driving current output by the driving circuit 120 is overcurrent.

[0058] In one embodiment, the acquisition circuit 1311 includes a first resistor R19 and a second resistor R20 connected in parallel, wherein a first end of the first resistor R19 and a first end of the second resistor R20 are connected to the driving circuit 120 and the voltage comparison circuit 1312, respectively, and a second end of the first resistor R19 and a second end of the second resistor R20 are commonly grounded.

[0059] Specifically, the acquisition circuit 1311 includes two parallel resistors, and the driving current output by the driving circuit 120 is converted into a driving voltage through the parallel resistors, which can reduce the acquisition cost of the driving voltage.

[0060] In one embodiment, the voltage comparison circuit 1312 includes a voltage comparator U7, a third resistor R21, a fourth resistor R22, a rollover timer, and a first capacitor C20. The negative input terminal of the voltage comparator U7 is respectively connected to the first end of the first resistor R19 and the drive circuit 120, the positive input terminal of the voltage comparator U7 is respectively connected to the second end of the third resistor R21 and the first end of the fourth resistor R22, the first capacitor C20 is connected between the first end of the third resistor R21 and the second end of the fourth resistor R22, and the output terminal of the voltage comparator U7 is connected to the rollover timer.

[0061] The voltage comparator U7 is used to output a corresponding voltage comparison signal based on the comparison result of the driving current and the voltage threshold. The flip timer is used to flip the level state of the voltage comparison signal and output it as a voltage detection signal after receiving the preset duration of the voltage comparison signal. The third resistor R21 and the fourth resistor R22 are used to set the voltage threshold.

[0062] Specifically, the voltage threshold of the reference terminal of the voltage comparator U7 is set by the third resistor R21 and the fourth resistor R22. The voltage comparator U7 compares the driving voltage with the voltage threshold and outputs a low-level voltage comparison signal when the driving voltage is greater than the voltage threshold, and outputs a high-level voltage comparison signal when the driving voltage is less than or equal to the voltage threshold. The rollover timer flips the voltage comparison signal and outputs it after receiving the voltage comparison signal for a preset duration. The preset duration can be customized according to actual needs. In this embodiment, the preset duration is 2 seconds. The rollover timer outputs a high-level voltage detection signal 2 seconds after receiving the low-level voltage comparison signal; and outputs a low-level voltage detection signal 2 seconds after receiving the high-level voltage comparison signal, thereby achieving signal delay processing.

[0063] In one embodiment, the first protection branch 1313 includes a first current-limiting resistor R23, a first pull-down resistor R24, a first pull-up resistor R25, a second pull-up resistor R26, a second capacitor C21, a first transistor Q1, and a second transistor Q3. The first end of the first current-limiting resistor R23 is respectively connected to the output end of the rollover timer and the second protection branch 1314. The second end of the first current-limiting resistor R23 is respectively connected to the first end of the first pull-down resistor R24 and the base of the second transistor Q3. The collector of the second transistor Q3 is respectively connected to the base of the first transistor Q1 and the first end of the first pull-up resistor R25. The emitter of the second transistor Q3 is commonly grounded with the second end of the second capacitor C21 and the emitter of the first transistor Q1. The second end of the first pull-up resistor R25 is connected to the first end of the second capacitor C21 and the first end of the second pull-up resistor R26. The node where the collector of the first transistor Q1 is connected to the second end of the second pull-up resistor R26 is used to output the second abnormality detection signal.

[0064] Specifically, when the voltage detection signal is at a low level, the second transistor Q3 in the first protection branch 1313 is cut off and the first transistor Q1 is turned on. At this time, the first protection branch 1313 outputs a low-level second abnormal detection signal, indicating that the driving current output by the driving circuit 120 is normal and there is no overcurrent phenomenon; when the voltage detection signal is at a high level, the second transistor Q3 is turned on and the first transistor Q1 is cut off. At this time, the first protection branch 1313 outputs a high-level second abnormal detection signal, indicating that the driving current output by the driving circuit 120 has an abnormal overcurrent phenomenon, and it is necessary to start the abnormal protection action to shut down the driving circuit 120 to avoid the overcurrent phenomenon from causing damage to the subsequent power module 200.

[0065] In one embodiment, the second protection branch 1314 includes a third pull-up resistor R28, a fourth pull-up resistor R29, a second pull-down resistor R31, a second current-limiting resistor R30, a third capacitor, and a third transistor Q4. The first end of the third pull-up resistor R28 is respectively connected to the output end of the rollover timer and the first end of the first current-limiting resistor R23, the second end of the third pull-up resistor R28 is respectively connected to the base of the third transistor Q4 and the first end of the second pull-down resistor R31, the collector of the third transistor Q4 is respectively connected to the first end of the fourth pull-up resistor R29 and the first end of the second current-limiting resistor R30, the emitter of the third transistor Q4, the second end of the second pull-down resistor R31, and the second end of the third capacitor are commonly grounded, and the node where the second end of the second current-limiting resistor R30 is connected to the first end of the third capacitor is used to output the second abnormal alarm signal when an abnormal state is determined based on the driving current.

[0066] Specifically, when the voltage detection signal is at a low level, the third transistor Q4 in the second protection branch 1314 is cut off. At this time, the second protection branch 1314 outputs a second normal alarm signal of a high level, indicating that the driving current output by the driving circuit 120 is normal and there is no overcurrent phenomenon; when the voltage detection signal is at a high level, the third transistor Q4 is turned on. At this time, the second protection branch 1314 outputs a second abnormal alarm signal of a low level, indicating that the driving current output by the driving circuit 120 has an abnormal overcurrent phenomenon, which is used to inform the user of the type of abnormality existing in the driving protection circuit.

[0067] In one embodiment, the second protection sub-circuit 132 includes a fourth transistor Q2, an inverter, a third pull-down resistor R27 and an OR gate OR. The base of the fourth transistor Q2 is respectively connected to the input end of the inverter and the drive circuit 120. The collector of the fourth transistor Q2 is grounded via the third pull-down resistor R27. The collector of the fourth transistor Q2 is also used to output a first alarm signal corresponding to the first abnormal protection signal when the fourth transistor Q2 is turned on. The output end of the inverter is connected to the first input end of the OR gate OR, the second input end of the OR gate OR is connected to the collector of the first transistor Q1, and the output end of the OR gate OR is used to output the abnormal protection signal.

[0068] Specifically, if the first abnormality detection signal is low (i.e., FLT is low), the fourth transistor Q2 is turned on. At this time, a low-level first abnormality alarm signal is output through the collector of the fourth transistor Q2. The low-level first abnormality detection signal is converted by the inverter into a high-level first input signal. If the second abnormality detection signal is low at this time, indicating that there is no overcurrent in the drive current, the low-level second abnormality detection signal serves as the second input signal, or the AND gate OR outputs a high-level abnormality protection signal based on the high-level first input signal and the low-level second input signal. This scenario indicates that only an overcurrent or overvoltage condition exists in the drive circuit 120, i.e., the DESAT protection is triggered.

[0069] If the first abnormality detection signal is low, the fourth transistor Q2 is turned on. At this time, a low-level first abnormality alarm signal is output through the collector of the fourth transistor Q2. The low-level first abnormality detection signal is converted into a high-level first input signal through the inverter. The second abnormality detection signal is high, indicating that the drive current is overcurrent. The high-level second abnormality detection signal serves as the second input signal, or the AND gate OR outputs a high-level abnormality protection signal based on the high-level first input signal and the high-level second input signal. This scenario indicates that not only is there an overcurrent or overvoltage in the drive circuit 120, but there is also an overcurrent in the drive current output by the drive circuit 120, triggering both DESAT protection and overcurrent protection.

[0070] If the first abnormality detection signal is high, the fourth transistor Q2 is cut off, and the collector of the fourth transistor Q2 outputs a high-level first normal alarm signal. The high-level first abnormality detection signal is converted by the inverter into a low-level first input signal. If the second abnormality detection signal is high at this time, it indicates that the drive current is overcurrent. The high-level second abnormality detection signal serves as the second input signal, or the AND gate OR outputs a high-level abnormality protection signal based on the low-level first input signal and the high-level second input signal. This scenario indicates that only the drive current output by the drive circuit 120 is overcurrent, and only the overcurrent protection is triggered.

[0071] If the first abnormality detection signal is high, the fourth transistor Q2 is cut off, and the collector of the fourth transistor Q2 outputs a high-level first normal alarm signal. The high-level first abnormality detection signal is converted by the inverter into a low-level first input signal. If the second abnormality detection signal is low at this time, it indicates that the drive current is not overcurrent. The low-level second abnormality detection signal serves as the second input signal, or the AND gate OR outputs a low-level normal protection signal based on the low-level first input signal and the low-level second input signal. This scenario indicates that neither overcurrent nor overvoltage exists in the drive circuit 120, and the drive current output by the drive circuit 120 does not have an overcurrent. Neither the DESAT protection nor the overcurrent protection is triggered.

[0072] The first abnormal alarm signal and the second abnormal alarm signal are used to make the alarm light present different display states. For example, when the DESAT protection is triggered, the yellow light flashes; when the overcurrent protection is triggered, the red light flashes; when the DESAT protection and overcurrent protection are triggered at the same time, the red and yellow light flashes.

[0073] In one embodiment, the driving circuit 120 includes a three-phase inverter bridge circuit, and each phase inverter bridge circuit includes two driving sub-circuits. Figure 5 Each of the driving sub-circuits includes a driving chip and a driving pull-up resistor, a first driving pull-down resistor, a second driving pull-down resistor, a third current limiting resistor, a fourth current limiting resistor, a first filter capacitor, a second filter capacitor, a third filter capacitor, a driving transistor, and a driving diode. The first power pin of the driving chip is connected to an external power supply, the second power pin of the driving chip is respectively connected to the first end of the driving pull-up resistor and the first end of the first filter capacitor, the second end of the driving pull-up resistor is connected to a fault pin of the driving chip, the positive input terminal of the driving chip is connected to the third current limiting resistor and the second filter capacitor, the negative input terminal of the driving chip is respectively connected to the fourth current limiting resistor and the third filter capacitor, the enable pin of the driving chip is connected to the base of the driving transistor, the voltage output pin of the driving chip is respectively connected to the emitter of the driving transistor and the positive electrode of the driving diode, the negative electrode of the driving diode is connected to the collector of the driving transistor, the fault pin of the driving chip is used to output a first abnormality detection signal according to the abnormal state of the DC voltage, and the driving chip stops outputting the driving signal when the negative input terminal receives an abnormal protection signal.

[0074] Specifically, refer to Figure 4In the driving circuit 120, U1, U2, U3, U4, U5, and U6 are different driving chips, R1, R4, R7, R10, R13, and R16 are pull-up resistors around the driving chip, R2, R3, R5, R6, R8, R9, R11, R12, R14, R15, R17, and R18 are current-limiting resistors around the driving chip, and C1, C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, and C18 are filter capacitors around the driving chip. The driver chip UP / U-UOUT is the U-phase upper bridge, and UN / N is the U-phase lower bridge; VP / V-VOUT is the U-phase upper bridge, and VN / N is the V-phase lower bridge; WP / W_OUT is the W-phase upper bridge, and WN / N is the W-phase lower bridge, which are respectively connected to the base and emitter of the corresponding upper and lower bridge arm IGBTs to provide driving capability (i.e. driving signal) for their IGBTs.

[0075] Each driver chip provides a first abnormality detection signal to the second protection sub-circuit 132. That is, the FLT pin of each driver signal is connected to the collector of the fourth transistor Q2 in the second protection sub-circuit 132. If at least one of the first abnormality detection signals is at a low level, the DESAT protection will be triggered. In addition, the output end of the OR gate in the second protection sub-circuit 132 is connected to the IN- pin of each driver chip. In this way, when the second protection sub-circuit 132 outputs the abnormality protection signal, the gate drive circuit 120 output is simultaneously shut down inside all driver chips, causing all driver chips to be interlocked and stop sending drive signals to protect the subsequent power module 200 from abnormal influences.

[0076] In a specific embodiment, referring to Figure 4 , the working conditions of the driving protection circuit are as follows:

[0077] 1. When the DESAT protection is triggered, the FLT pin outputs a low level, Q2 turns on, and FLT_DSP turns low. The low level output of the FLT pin is converted to a high level by the inverter. At this time, the overcurrent protection is not triggered. The drive current flowing through the driver circuit 120 (IGBT) is detected by the sampling resistors (R19, R20) and converted into a drive voltage. This voltage is connected to the negative terminal of the comparator U7 and compared with the voltage threshold L. If it is less than the voltage threshold L, the output is high. The 555 timer NOT gate (flip timer) outputs a low level, Q3 turns off, Q1 turns on, Q4 turns off, TCBH outputs a low level, and FO_DSP turns high. The low level output of the FLT pin is converted to a high level by the A NOT gate (inverter) and the TCBH output is low. The OR gate outputs a high level. At this time, the driver chip voltage level is: FLT pin is low, IN+ is high, IN- is high, FLT_DSP is low, and FO_DSP is high. The first abnormal alarm signal corresponding to the DESAT protection is output.

[0078] 2. At this point, the DESAT protection is not triggered, the FLT pin outputs a high level, Q2 is off, and FLT_DSP is high. The high level output from the FLT pin is converted to a low level by the A-inverter gate. When the overcurrent protection is triggered, the current flowing through the IGBT is detected by the sampling resistor and connected to the negative terminal of comparator U7 for comparison with the voltage threshold L. If it exceeds the voltage threshold L, the output is low. The 555 timer's NOT gate output is high, Q3 turns on, Q1 turns off, Q4 turns on, TCBH output is high, and FO_DSP is low. The high level output from the FLT pin is converted to a low level by the A-inverter gate and combined with the high level output from TCBH, the output is high by the OR gate. At this time, the driver chip voltage level is FLT pin high, IN+ high, and IN- high. FLT_DSP is high, FO_DSP is low, and the second abnormal alarm signal corresponding to the IPM overcurrent protection is output.

[0079] 3. At this point, the DESAT protection is not triggered. The FLT pin outputs a high level, Q2 is off, and FLT_DSP is high. The high level output of the FLT pin is converted to a low level by the A-inverter gate. At this point, the overcurrent protection is not triggered. The current flowing through the IGBT is detected by the sampling resistor and connected to the negative terminal of comparator U7 for comparison with the positive terminal of voltage threshold L. If it is less than voltage threshold L, the output is high. The 555 timer's NOT gate output is low, Q3 is off, Q1 is on, Q4 is off, TCBH output is low, and FO_DSP is high. The high level output of the FLT pin is converted to a low level by the A-inverter gate and combined with the TCBH output low. The output is low by the OR gate. At this point, the driver chip voltage level is FLT pin high, IN+ is high, and IN- is low. If FLT_DSP and FO_DSP are high, no abnormal protection signal is reported.

[0080] 4. When DESAT protection is triggered, the FLT pin outputs a low level, Q2 turns on, and FLT_DSP is low. The low level output of the FLT pin is converted to a high level by the A-inverter gate. When overcurrent protection is triggered, the current flowing through the IGBT is detected by the sampling resistor and connected to the negative terminal of comparator U7 for comparison with the positive terminal of voltage threshold L. If it exceeds voltage threshold L, the output is low. The 555 timer's A-inverter gate output is high, Q3 turns on, Q1 turns off, Q4 turns on, TCBH output is high, and FO_DSP is low. The low level output of the FLT pin is converted to a high level by the A-inverter gate and combined with the high level of TCBH output, the output is high by the OR gate. At this time, the driver chip voltage level is high, FLT pin high, IN+ high, and IN- high. FLT_DSP low and FO_DSP low, outputting the second abnormal alarm signal corresponding to the IPM overcurrent protection and the first abnormal alarm signal corresponding to the DESAT protection.

[0081] In one embodiment, an electronic device is provided. The electronic device includes an electrically connected power module 200 and the driving protection circuit as described in any one of the above embodiments.

[0082] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the modules may be selected based on actual needs to achieve the objectives of this embodiment.

[0083] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a general hardware platform, or of course by hardware. Based on this understanding, the above technical solution, in essence, or the part that contributes to the relevant technology, can be embodied in the form of a software product. The computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions for enabling an electronic device (which can be a personal computer, a server, or a network device, etc.) to execute the driving protection circuit described in each embodiment or certain parts of the embodiment.

[0084] It should be understood that the terms used herein are for the purpose of describing specific example embodiments only and are not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms "one", "an", and "said" as used herein may also be meant to include plural forms. The terms "comprise", "include", "contain", and "have" are inclusive and therefore specify the presence of the stated features, steps, operations, elements, and / or parts, but do not exclude the presence or addition of one or more other features, steps, operations, elements, parts, and / or combinations thereof. The drive protection circuit steps, processes, and operations described herein are not to be construed as necessarily requiring them to be performed in the specific order described or illustrated, unless the order of execution is clearly indicated. It should also be understood that additional or alternative methods may be used.

[0085] The foregoing description is intended only to provide specific embodiments of the present invention, which will enable those skilled in the art to understand and implement the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not intended to be limited to the embodiments shown herein, but is intended to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A driving protection circuit, characterized in that: The driving protection circuit includes: A rectifier bridge circuit is used to convert the input three-phase AC power into a DC voltage; a drive circuit, wherein an input end of the drive circuit is connected to an output end of the rectifier bridge circuit, the drive circuit outputs a first abnormality detection signal according to an abnormal state of the DC voltage, and provides a drive signal to a power module when the first abnormality detection signal indicates a normal state, the power module being configured to drive a load according to the drive signal; An abnormality protection circuit is connected to the drive circuit, and when receiving the first abnormality detection signal indicating an abnormal state, the abnormality protection circuit outputs an abnormality protection signal and a first abnormality alarm signal according to the first abnormality detection signal; it is also used to detect the drive current output by the drive circuit, and output an abnormality protection signal and a second abnormality alarm signal when determining an abnormal state based on the drive current, the first abnormality alarm signal and the second abnormality alarm signal indicating different abnormal types, and the abnormality protection signal is used to prohibit the drive circuit from outputting a drive signal.

2. The driving protection circuit according to claim 1, characterized in that: The abnormal protection circuit includes: a first protection subcircuit, the first protection subcircuit being connected to the drive circuit and configured to detect a drive current of the drive circuit, output a second abnormality detection signal according to an abnormal state of the drive current, and output a second abnormality alarm signal when an abnormal state is determined according to the drive current; The second protection subcircuit is connected to the driving circuit and the first protection subcircuit respectively, and is used to output the abnormal protection signal when at least one of the first abnormality detection signal and the second abnormality detection signal indicates an abnormal state.

3. The driving protection circuit according to claim 2, characterized in that: The first protection sub-circuit includes: an acquisition circuit, connected to the drive circuit, and configured to convert the drive current of the drive circuit into a drive voltage; a voltage comparison circuit, wherein an input end of the voltage comparison circuit is connected to an output end of the acquisition circuit, and is configured to output a low-level voltage detection signal when the driving voltage is less than or equal to a voltage threshold, or output a high-level voltage detection signal when the driving voltage is greater than the voltage threshold; a first protection branch, wherein an input end of the first protection branch is connected to an output end of the voltage comparison circuit, and is configured to output a corresponding second abnormality detection signal according to a level state of the voltage detection signal; The second protection branch has an input end connected to the output end of the voltage comparison circuit, and is used to output the second abnormal alarm signal when the level state of the voltage detection signal is high.

4. The driving protection circuit according to claim 3, characterized in that: The acquisition circuit includes a first resistor and a second resistor connected in parallel, wherein a first end of the first resistor and a first end of the second resistor are respectively connected to the drive circuit and the voltage comparison circuit, and a second end of the first resistor and a second end of the second resistor are commonly grounded.

5. The driving protection circuit according to claim 4, characterized in that: The voltage comparison circuit includes a voltage comparator, a third resistor, a fourth resistor, a rollover timer, and a first capacitor, wherein the negative input terminal of the voltage comparator is connected to the first end of the first resistor and the driving circuit respectively, the positive input terminal of the voltage comparator is connected to the second end of the third resistor and the first end of the fourth resistor respectively, the first capacitor is connected between the first end of the third resistor and the second end of the fourth resistor, and the output terminal of the voltage comparator is connected to the rollover timer; The voltage comparator is used to output a corresponding voltage comparison signal based on the comparison result of the driving current and the voltage threshold, and the flip timer is used to flip the level state of the voltage comparison signal and output it as a voltage detection signal after receiving the preset duration of the voltage comparison signal, wherein the third resistor and the fourth resistor are used to set the voltage threshold.

6. The driving protection circuit according to claim 5, characterized in that: The first protection branch includes a first current limiting resistor, a first pull-down resistor, a first pull-up resistor, a second pull-up resistor, a second capacitor, a first transistor, and a second transistor. The first end of the first current limiting resistor is respectively connected to the output end of the rollover timer and the second protection branch, the second end of the first current limiting resistor is respectively connected to the first end of the first pull-down resistor and the base of the second transistor, the collector of the second transistor is respectively connected to the base of the first transistor and the first end of the first pull-up resistor, the emitter of the second transistor, the second end of the second capacitor, and the emitter of the first transistor are commonly grounded, the second end of the first pull-up resistor is connected to the first end of the second capacitor and the first end of the second pull-up resistor, and the node where the collector of the first transistor is connected to the second end of the second pull-up resistor is used to output the second abnormality detection signal.

7. The driving protection circuit according to claim 6, characterized in that: The second protection branch includes a third pull-up resistor, a fourth pull-up resistor, a second pull-down resistor, a second current-limiting resistor, a third capacitor and a third transistor. The first end of the third pull-up resistor is respectively connected to the output end of the rollover timer and the first end of the first current-limiting resistor, the second end of the third pull-up resistor is respectively connected to the base of the third transistor and the first end of the second pull-down resistor, the collector of the third transistor is respectively connected to the first end of the fourth pull-up resistor and the first end of the second current-limiting resistor, the emitter of the third transistor is commonly grounded with the second end of the second pull-down resistor and the second end of the third capacitor, and the node where the second end of the second current-limiting resistor is connected to the first end of the third capacitor is used to output the second abnormal alarm signal when an abnormal state is determined based on the driving current.

8. The driving protection circuit according to claim 7, characterized in that: The second protection subcircuit includes a fourth transistor, an inverter, a third pull-down resistor and an OR-AND gate. The base of the fourth transistor is respectively connected to the input end of the inverter and the drive circuit. The collector of the fourth transistor is grounded via the third pull-down resistor. The collector of the fourth transistor is also used to output a first alarm signal corresponding to the first abnormal protection signal when the fourth transistor is turned on. The output end of the inverter is connected to the first input end of the OR-AND gate, the second input end of the OR-AND gate is connected to the collector of the first transistor, and the output end of the OR-AND gate is used to output the abnormal protection signal.

9. The driving protection circuit according to claim 8, characterized in that: The drive circuit includes a three-phase inverter bridge circuit, each phase inverter bridge circuit includes two drive sub-circuits, each of the drive sub-circuits includes a drive chip and a drive pull-up resistor, a first drive pull-down resistor, a second drive pull-down resistor, a third current limiting resistor, a fourth current limiting resistor, a first filter capacitor, a second filter capacitor, a third filter capacitor, a drive transistor and a drive diode, the first power pin of the drive chip is connected to an external power supply, the second power pin of the drive chip is respectively connected to the first end of the drive pull-up resistor and the first end of the first filter capacitor, the second end of the drive pull-up resistor is connected to the fault pin of the drive chip, and the drive chip The positive input terminal of the driver chip is connected to the third current limiting resistor and the second filter capacitor, the negative input terminal of the driver chip is respectively connected to the fourth current limiting resistor and the third filter capacitor, the enable pin of the driver chip is connected to the base of the driver transistor, the voltage output pin of the driver chip is respectively connected to the emitter of the driver transistor and the positive electrode of the driver diode, the negative electrode of the driver diode is connected to the collector of the driver transistor, the fault pin of the driver chip is used to output a first abnormality detection signal according to the abnormal state of the DC voltage, and the driver chip stops outputting the drive signal when receiving the abnormal protection signal at the negative input terminal.

10. An electronic device, characterized in that: The electronic device includes an electrically connected power module and a driving protection circuit according to any one of claims 1 to 9.

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