Load power supply circuit, motor controller and power supply control module

Abstract

The utility model discloses a load power supply circuit, a motor controller and a power supply control module, and relates to the technical field of power supply, and the circuit comprises a switching device, a voltage sampling circuit and a judgment circuit. A voltage sampling circuit is arranged between a switching device connected with the negative electrode of a load power supply and a first load interface used for being connected with an external load so as to collect the interface voltage at the first load interface and generate a corresponding voltage sampling signal. And outputting the voltage sampling signal and a control signal of the switching device to a judgment circuit. According to the voltage value corresponding to the voltage sampling signal and the voltage value of the control signal, the judgment circuit confirms whether the interface voltage and the voltage value of the control signal are matched with the corresponding condition when the switching device is switched on or switched off, so that whether the switching device breaks down or not can be effectively judged under the condition that a load is not connected. And a fault source can be quickly checked when the circuit has a fault, so that the fault processing efficiency is improved.

Description

Technical Field

[0001] This application relates to the field of power supply technology, and in particular to a load power supply circuit, a motor controller, and a power control module. Background Technology

[0002] In existing technologies, for some high-power electromechanical devices or electric vehicles, internal electrical accessory switches are essential to ensure internal electrical safety. Correspondingly, the status detection of these electrical accessory switches is also crucial, and current-based methods are commonly used. However, the current-based method requires sampling the current of a shunt for judgment, and this method can only determine whether a fault has occurred in the entire circuit consisting of the electrical accessory switch and the external load, but cannot determine whether the fault lies with the internal switching device or the external load. Voltage-based methods require significant additional hardware, resulting in high costs. Utility Model Content

[0003] The main purpose of this application is to provide a load power supply circuit, a motor controller, and a power control module, which aims to solve the technical problem of how to determine whether a switching device has failed when no external load is connected.

[0004] To achieve the above objectives, this application provides a load power supply circuit, which includes: a voltage sampling circuit, a switching device, and a judgment circuit;

[0005] The input terminal of the voltage sampling circuit is connected to the first load interface and the first terminal of the switching device, and the output terminal of the voltage sampling circuit is connected to the first input terminal of the judgment circuit; the voltage sampling circuit is used to collect the interface voltage at the first load interface and output the corresponding voltage sampling signal to the judgment circuit.

[0006] The second terminal of the switching device is connected to the negative terminal of the load power supply, and the second load interface is connected to the positive terminal of the load power supply; the first load interface and the second load interface are used to connect to an external load.

[0007] The judgment circuit is used to determine whether the switching device is faulty based on the control signal of the switching device and the voltage sampling signal.

[0008] In one embodiment, the voltage sampling circuit includes: an optocoupler and a first resistor;

[0009] The primary anode of the optocoupler is connected to a first power supply, the primary cathode of the optocoupler is connected to the first load interface, the secondary first terminal of the optocoupler is connected to the second terminal of the first resistor and the external load of the first input terminal of the judgment circuit, and the secondary second terminal of the optocoupler is grounded; the first terminal of the first resistor is connected to a second power supply.

[0010] In one embodiment, the load power supply circuit further includes: a unidirectional conduction circuit;

[0011] The input terminal of the unidirectional conduction circuit is connected to the first power supply, and the output terminal of the unidirectional conduction circuit is connected to the primary anode of the optocoupler.

[0012] The unidirectional conduction circuit is used to prevent the interface voltage from flowing back to the first power supply.

[0013] In one embodiment, the unidirectional conduction circuit includes: a first diode;

[0014] The anode of the first diode is connected to the first power supply, and the cathode of the first diode is connected to the primary anode of the optocoupler.

[0015] In one embodiment, the load power supply circuit further includes: a first current limiting circuit;

[0016] The first end of the first current limiting circuit is connected to the first power supply, and the second end of the first current limiting circuit is connected to the primary anode of the optocoupler.

[0017] The first current limiting circuit is used to limit the current output to the voltage sampling circuit to not exceed a first current threshold.

[0018] In one embodiment, the first current limiting circuit includes: a second resistor;

[0019] The first end of the second resistor is connected to the first power supply, and the second end of the second resistor is connected to the primary anode of the optocoupler.

[0020] In one embodiment, the load power supply circuit further includes: a second diode;

[0021] The positive terminal of the second diode is connected to the first load interface, and the positive terminal of the second diode is connected to the second load interface.

[0022] In one embodiment, the load power supply circuit further includes: a third resistor;

[0023] The first end of the third resistor is connected to the negative terminal of the load power supply, and the second end of the third resistor is connected to the second terminal of the switching device.

[0024] In one embodiment, the load power supply circuit further includes: a current sampling circuit;

[0025] The first input terminal of the current sampling circuit is connected to the first terminal of the third resistor, the second input terminal of the current sampling circuit is connected to the second terminal of the third resistor, and the output terminal of the current sampling circuit is connected to the second input terminal of the judgment circuit.

[0026] The current sampling circuit is used to collect the current flowing through the third resistor and output the corresponding current sampling signal to the judgment circuit.

[0027] The judgment circuit is also used to determine whether the external load is faulty based on the current sampling signal.

[0028] In addition, to achieve the above objectives, this application also provides a motor controller, including the load power supply circuit as described above.

[0029] In addition, to achieve the above objectives, this application also provides a power control module, including the load power supply circuit as described above.

[0030] This application provides a load power supply circuit, a motor controller, and a power control module. The load power supply circuit includes a voltage sampling circuit, a switching device, and a judgment circuit. The input terminal of the voltage sampling circuit is connected to a first load interface and a first terminal of the switching device, and the output terminal of the voltage sampling circuit is connected to the first input terminal of the judgment circuit. The voltage sampling circuit is used to collect the interface voltage at the first load interface and output a corresponding voltage sampling signal to the judgment circuit. The second terminal of the switching device is connected to the negative terminal of the load power supply, and the second load interface is connected to the positive terminal of the load power supply. The first load interface and the second load interface are used to connect an external load. The judgment circuit is used to determine whether the switching device is faulty based on the control signal of the switching device and the voltage sampling signal.

[0031] A voltage sampling circuit is installed between a switching device connected to the negative terminal of the power supply and a first load interface for connecting an external load. This circuit collects the interface voltage at the first load interface and generates a corresponding voltage sampling signal. The voltage sampling signal and the control signal from the switching device are output to a judgment circuit. The judgment circuit determines whether the interface voltage matches the control signal's voltage value, based on the voltage value of the sampling signal and the control signal. This allows for effective judgment of whether the switching device is faulty even without a load connected, facilitating rapid fault identification and improving fault handling efficiency. Attached Figure Description

[0032] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0033] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1 This is a structural connection diagram provided for Embodiment 1 of the load power supply circuit of this application;

[0035] Figure 2 The circuit connection diagram provided for Embodiment 2 of the load power supply circuit of this application.

[0036] The purpose, features, and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0037] It should be understood that the specific embodiments described herein are merely illustrative of the technical solutions of this application and are not intended to limit this application.

[0038] To better understand the technical solution of this application, a detailed description will be provided below in conjunction with the accompanying drawings and specific implementation methods.

[0039] This application presents a load power supply circuit according to a first embodiment. Please refer to [link / reference]. Figure 1 The load power supply circuit includes: a voltage sampling circuit 10, a switching device 30, and a judgment circuit 20;

[0040] The input terminal of the voltage sampling circuit 10 is connected to the first load interface and the first terminal of the switching device 30, and the output terminal of the voltage sampling circuit 10 is connected to the first input terminal of the judgment circuit 20; the voltage sampling circuit 10 is used to collect the interface voltage at the first load interface and output the corresponding voltage sampling signal to the judgment circuit 20.

[0041] The second terminal of the switching device 30 is connected to the negative terminal of the load power supply, and the second load interface is connected to the positive terminal of the load power supply; the first load interface and the second load interface are used to connect an external load 40.

[0042] The judgment circuit 20 is used to determine whether the switching device 30 is faulty based on the control signal of the switching device 30 and the voltage sampling signal.

[0043] It should be understood that the switching device 30 can be understood as a switching transistor or other type of electronically controlled switching device, whose control terminal is used to receive externally transmitted control signals (not shown in the figure), and can control the on / off state of the connection circuit at both ends of the switching device 30 according to the control signals. In this embodiment, the switching device 30 can control the on / off state of the connection circuit between the negative terminal of the load power supply and the second load interface.

[0044] It should be noted that the load power supply refers to the power supply used to provide power to the external load 40 (not shown in the figure). In this embodiment, when the switching device 30 is in the on state and the first load interface and the second load interface are connected to the external load 40, the positive terminal of the load power supply, the second load interface, the external load 40, the first load interface, the switching device 30, and the negative terminal of the load power supply form a connection loop, and the load power supply can supply power to the external load 40 so that the external load 40 can work. When the switching device 30 is in the off state or one of the first load interface and the second load interface is not connected to the external load 40, the positive terminal of the load power supply, the second load interface, the external load 40, the first load interface, the switching device 30, and the negative terminal of the load power supply cannot form a connection loop, and the load power supply cannot supply power to the external load 40.

[0045] As is readily understood, in this embodiment, the voltage sampling circuit 10 is connected to the first load interface, which can collect the interface voltage at the first load interface and generate a voltage sampling signal with a corresponding voltage value. The voltage sampling signal is then transmitted to the judgment circuit 20. The judgment circuit 20 can determine whether the switching device 30 has malfunctioned based on the voltage of the acquired voltage sampling signal and the voltage of the control signal of the switching device 30.

[0046] It is worth noting that in this embodiment, the judgment circuit 20 can obtain the control signal received by the switching device 30 by connecting to the control terminal of the switching device 30, or it can directly generate the corresponding control signal internally or obtain the corresponding control signal directly from the external controller in other ways. The specific method by which the judgment circuit 20 obtains the control signal is not limited.

[0047] In a more specific scenario, the switching device 30 can be an IGBT transistor, whose gate is used to receive control signals. If the switching device 30 receives a high-level control signal, it can enter the on state, allowing the negative terminal of the load power supply to be connected to the first load interface through the switching device 30. If the switching device 30 receives a low-level control signal, it can enter the off state, preventing the negative terminal of the load power supply from being connected to the first load interface through the switching device 30. Based on these two scenarios, regardless of whether the first load interface or the second load interface is connected to an external load 40, when the interface voltage is higher than a preset voltage threshold, the voltage sampling circuit 10 can output a high-level voltage sampling signal. When the first load interface is open-circuited, the voltage sampling circuit 10 defaults to outputting a high-level voltage sampling signal. When the interface voltage is lower than the preset voltage threshold, the voltage sampling circuit 10 outputs a low-level voltage sampling signal.

[0048] In practical implementation, when the first load interface and the second load interface are not connected to the external load 40, if the switching device 30 receives a high-level control signal, theoretically, the switching device 30 should be in the on state. The first load interface is equivalent to the negative terminal of the load power supply directly connected, and the corresponding interface voltage should be the voltage provided by the negative terminal of the load power supply, which is less than the preset voltage threshold. The corresponding voltage sampling circuit 10 should output a low-level voltage sampling signal. If the switching device 30 receives a low-level control signal, theoretically, the switching device 30 should be in the off state, and the interface voltage at the first load interface should be equivalent to an open circuit. The corresponding voltage sampling circuit 10 should output a high-level voltage sampling signal. When external load 40 is connected to the first and second load interfaces, if the switching device 30 receives a high-level control signal, theoretically, the switching device 30 should be in the ON state. The first load interface is still equivalent to being directly connected to the negative terminal of the load power supply, and the corresponding interface voltage should be the voltage provided by the negative terminal of the load power supply. The corresponding voltage sampling circuit 10 should output a low-level voltage sampling signal. If the switching device 30 receives a low-level control signal, then theoretically, the switching device 30 should be in the OFF state. The interface voltage at the first load interface should be equal to the high level provided by the positive terminal of the load power supply, and the corresponding voltage sampling circuit 10 should output a high-level voltage sampling signal. In an abnormal situation, if the judgment circuit 20 receives both a high-level control signal and a high-level voltage sampling signal, it can be considered that the switching device 30 should be in the ON state but is actually in the OFF state, and thus a circuit breaker fault is determined to have occurred in the current switching device 30. In another abnormal situation, when the switching device 30 receives a low-level control signal and a low-level voltage sampling signal, it can be assumed that the switching device 30 should be in the off state but is actually in the on state, and a short circuit fault is determined to have occurred in the current switching device 30.

[0049] Based on the above theoretical relationships, regardless of whether an external load 40 is connected or not, when the switching device 30 is not faulty, the control signal and voltage sampling signal levels will always be one high and one low; when the switching device 30 experiences an open-circuit fault, the control signal and voltage sampling signal levels will both be high; and when the switching device 30 experiences a short-circuit fault, the control signal and voltage sampling signal levels will both be low. Therefore, regardless of whether an external load 40 is currently connected, the judgment circuit 20 can directly determine whether the switching device 30 has faulted based on the voltage of the acquired control signal and the voltage of the voltage sampling signal, and can also determine its specific fault type. The specific judgment logic can be found in the truth table for switching device fault determination provided in Table 1.

[0050] Connection status of external load voltage of control signal Voltage of voltage sampling signal Fault diagnosis connect 0 1 No fault connect 0 0 Short circuit fault connect 1 0 No fault connect 1 1 Open circuit fault Not connected 0 1 No fault Not connected 0 0 Short circuit fault Not connected 1 0 No fault Not connected 1 1 Open circuit fault

[0051] Table 1: Truth Table for Fault Judgment of Switching Devices

[0052] In the truth table, "0" represents a low level and "1" represents a high level.

[0053] This application provides a load power supply circuit, which includes a voltage sampling circuit, a switching device, and a judgment circuit. A voltage sampling circuit is set between the switching device connected to the negative terminal of the load power supply and a first load interface for connecting an external load to collect the interface voltage at the first load interface and generate a corresponding voltage sampling signal. The voltage sampling signal and the control signal of the switching device are output to the judgment circuit. The judgment circuit determines whether the interface voltage and the control signal match the switching device's on or off state based on the voltage value corresponding to the voltage sampling signal and the voltage value of the control signal. This allows for effective judgment of whether the switching device is faulty even without a load connected, facilitating rapid troubleshooting and improving fault handling efficiency when a circuit fault occurs.

[0054] Based on the first embodiment of this application, in the second embodiment of this application, the content that is the same as or similar to that in Embodiment 1 above can be referred to the above description, and will not be repeated hereafter. Based on this, please refer to... Figure 2 The voltage sampling circuit 10 includes: an optocoupler U0 and a first resistor R1;

[0055] The primary anode of the optocoupler U0 is connected to the first power supply, the primary cathode of the optocoupler U0 is connected to the first load interface, the secondary first terminal of the optocoupler U0 is connected to the second terminal of the first resistor R1 and the first input terminal of the judgment circuit 20, the external load 40, and the secondary second terminal of the optocoupler U0 is grounded; the first terminal of the first resistor R1 is connected to the second power supply.

[0056] It should be noted that in this embodiment, the first power supply VCC1 is used to provide a reference first voltage for the primary anode of the optocoupler U0, and the second power supply VCC2 can provide a second voltage. The reference voltage for both the first and second voltages is the voltage provided by the negative terminal of the load power supply. Furthermore, the first power supply VCC1 is much lower than the voltage provided by the positive terminal of the load power supply. The first and second voltages may not be the same. The value range of the second voltage needs to be set within the voltage range that the judgment circuit 20 can recognize, while the first voltage has no such limitation.

[0057] In a specific implementation, as one scenario, when no external load 40 is connected, if the switching device 30 receives a high-level control signal and enters the conducting state, the first load interface is equivalent to being connected to the negative terminal of the load power supply, and the corresponding interface voltage is the voltage provided by the negative terminal of the load power supply. The first voltage at the anode of the primary side of the optocoupler U0 is greater than the interface voltage at the first load interface, so the optocoupler U0 is turned on, and the second end of the first resistor R1 is equivalent to being grounded, that is, the first input terminal of the judgment circuit 20 is equivalent to being grounded, and the judgment circuit 20 can receive a low-level voltage sampling signal. When the switching device 30 receives a low-level control signal and enters the off state, the first load interface is disconnected, the optocoupler U0 does not work, the first resistor R1 connects the second power supply VCC2 and the first input terminal of the judgment circuit 20, and the judgment circuit 20 can receive the second voltage provided by the second power supply VCC2, that is, receive a high-level voltage sampling signal.

[0058] In another scenario, when an external load 40 is connected, if the switching device 30 receives a high-level control signal and enters the on state, the first load interface remains equivalent to the negative terminal of the load power supply, and the corresponding interface voltage is the voltage provided by the negative terminal of the load power supply. The first voltage at the anode of the primary side of the optocoupler U0 is greater than the interface voltage at the first load interface, so the optocoupler U0 is on. The second terminal of the first resistor R1 is equivalent to ground, meaning the first input terminal of the judgment circuit 20 is also grounded, and the judgment circuit 20 can receive a low-level voltage sampling signal. Conversely, when the switching device 30 receives a low-level control signal and enters the off state, the first load interface is connected to the positive terminal of the load power supply through the external load 40 and the second load interface. The first voltage at the anode of the primary side of the optocoupler U0 is less than the interface voltage at the first load interface, so the optocoupler U0 is off. The first resistor R1 connects the second power supply VCC2 and the first input terminal of the judgment circuit 20, and the judgment circuit 20 can receive the second voltage provided by the second power supply VCC2, i.e., it receives a high-level voltage sampling signal.

[0059] Based on the ideal scenarios described above, regardless of whether an external load 40 is connected, as long as the control signal and voltage sampling signal received by the judgment circuit 20 maintain a high and low level respectively, it can be determined that the current switching device 30 has not malfunctioned.

[0060] Furthermore, in this embodiment, the load power supply circuit further includes: a unidirectional conduction circuit 50;

[0061] The input terminal of the unidirectional conduction circuit 50 is connected to the first power supply, and the output terminal of the unidirectional conduction circuit 50 is connected to the primary anode of the optocoupler U0.

[0062] The unidirectional conduction circuit 50 is used to prevent the interface voltage from flowing back to the first power supply VCC1.

[0063] It should be noted that in this embodiment, when the external load 40 is connected and the switching device 30 is in the off state, the positive terminal of the load power supply, the second load interface, the external load 40, the first load interface, the optocoupler U0, and the first power supply VCC1 form a connection loop. At this time, the voltage provided by the positive terminal of the load power supply is much higher than the voltage provided by the first power supply VCC1, which can cause voltage reverse flow at the first power supply VCC1 and damage the first power supply VCC1.

[0064] It is easy to understand that a one-way conduction circuit 50 can be set between the optocoupler U0 and the first power supply VCC1. The one-way conduction circuit 50 only allows voltage to be supplied from the first power supply VCC1 to the first load interface, while preventing the interface voltage supplied by the first load interface from flowing back to the first power supply VCC1 through the optocoupler U0. In specific implementation, when the interface voltage is higher than the first voltage output by the first power supply VCC1, the one-way conduction circuit 50 is in the off state, automatically cutting off the connection loop between the optocoupler U0 and the first power supply VCC1, making the optocoupler U0 and the first power supply VCC1 in an open circuit state. This can prevent excessively high interface voltage from flowing back to the primary cathode of the optocoupler U0 or the first power supply VCC1 for a long time, causing damage to both. When the voltage output by the first power supply VCC1 is higher than the interface voltage, the one-way conduction circuit 50 is in the conducting state, which can normally conduct the connection loop between the optocoupler U0 and the first power supply VCC1, allowing the first power supply VCC1 and the optocoupler U0 to work normally.

[0065] Furthermore, in this embodiment, the unidirectional conduction circuit 50 includes: a first diode D1;

[0066] The anode of the first diode D1 is connected to the first power supply, and the cathode of the first diode D1 is connected to the primary anode of the optocoupler U0.

[0067] In this embodiment, the first diode D1 can be positioned between the primary anode of the optocoupler U0 and the first power supply VCC1, with the anode of the first diode D1 connected to the first power supply VCC1. Because the diode has unidirectional conduction characteristics, when the interface voltage is much higher than the first voltage, the first diode D1 enters the cutoff state, effectively creating an open circuit between the first diode D1 and the first load interface. Excessively high interface voltage will not break down the optocoupler U0, nor will it backflow into the first power supply VCC1, causing damage to VCC1. When the interface voltage is lower than the first voltage, the first diode D1 enters the conduction state, allowing the first voltage provided by the first power supply VCC1 to be normally applied to both the primary anode and primary cathode of the optocoupler U0, enabling the optocoupler U0 to normally enter the conduction state.

[0068] Furthermore, in this embodiment, the load power supply circuit further includes: a first current limiting circuit 60;

[0069] The first end of the first current limiting circuit 60 is connected to the first power supply, and the second end of the first current limiting circuit 60 is connected to the primary anode of the optocoupler U0.

[0070] The first current limiting circuit 60 is used to limit the current output to the voltage sampling circuit 10 to not exceed a first current threshold.

[0071] It should be noted that the first current threshold refers to the maximum safe current value that each electronic device in the circuit can withstand. In this embodiment, a first current limiting circuit 60 can also be provided between the first power supply VCC1 and the optocoupler U0. The first current limiting circuit 60 can also coexist with the unidirectional conduction circuit 50 in series. The specific relative positional relationship between the two is not specifically limited (the figure only shows the case where the first current limiting circuit 60 is set between the first power supply VCC1 and the unidirectional conduction circuit 50). In specific implementation, the first current limiting circuit 60 can at least limit the current flowing through the voltage sampling circuit 10 (optocoupler U0) and the first power supply VCC1 to prevent damage to the electronic devices due to the current value in the circuit exceeding the maximum safe current (first current threshold) that each electronic device in the circuit can withstand.

[0072] Furthermore, in this embodiment, the first current limiting circuit 60 includes: a second resistor R2;

[0073] The first end of the second resistor R2 is connected to the first power supply, and the second end of the second resistor R2 is connected to the primary anode of the optocoupler U0.

[0074] It is easy to understand that in this embodiment, the second resistor R2 can be used as a current-limiting resistor to limit the current flowing through the circuit from exceeding the first current threshold.

[0075] Furthermore, in this embodiment, the load power supply circuit further includes: a second diode D2;

[0076] The positive terminal of the second diode D2 is connected to the first load interface, and the positive terminal of the second diode D2 is connected to the second load interface.

[0077] It is easy to understand that in this embodiment, the external load 40 can be an inductive load, and the second diode D2 can be used as a freewheeling diode. When the switching device 30 suddenly switches from the on state to the off state, the external load 40 and the second diode D2 can form a freewheeling circuit, releasing the electrical energy stored in the inductance inside the external load 40 through the second diode D2, thereby protecting the entire circuit from damage caused by transient current surges.

[0078] Furthermore, in this embodiment, the load power supply circuit further includes: a third resistor R3;

[0079] The first end of the third resistor R3 is connected to the negative terminal of the load power supply, and the second end of the third resistor R3 is connected to the second terminal of the switching device 30.

[0080] It should be noted that in this embodiment, the third resistor R3 is used as a current-limiting resistor to limit the current flowing through the switching device 30, so as to prevent the switching device 30 from being damaged due to excessive current flowing through it when the switching device 30 is in the on state.

[0081] Furthermore, in this embodiment, the load power supply circuit further includes: a current sampling circuit 70;

[0082] The first input terminal of the current sampling circuit 70 is connected to the first terminal of the third resistor R3, the second input terminal of the current sampling circuit 70 is connected to the second terminal of the third resistor R3, and the output terminal of the current sampling circuit 70 is connected to the second input terminal of the judgment circuit 20.

[0083] The current sampling circuit 70 is used to collect the current flowing through the third resistor R3 and output the corresponding current sampling signal to the judgment circuit 20.

[0084] The judgment circuit 20 is also used to determine whether the external load 40 is faulty based on the current sampling signal.

[0085] It should be noted that the current sampling signal refers to the electrical signal generated after the current sampling circuit 70 collects the current flowing through the third resistor R3, which can represent the magnitude of the current flowing through the third resistor R3. In this embodiment, a current sampling circuit 70 can also be connected in parallel across the third resistor R3. The current sampling circuit 70 collects the voltage across the third resistor R3 and obtains the current flowing through the third resistor R3 according to the preset impedance value of the third resistor R3. Since the third resistor R3 is connected in series with the negative terminal of the load power supply, theoretically, if an external load 40 is connected, the current flowing through the third resistor R3 should be equal to the current flowing through the external load 40. Therefore, the magnitude of the current flowing through the external load 40 can be determined by the voltage value of the current sampling signal.

[0086] It is easy to understand that, in practical situations, it is difficult to determine whether the external load 40 has failed based solely on the above-described judgment logic. In this embodiment, to further improve the power supply safety of the external load 40, when the circuit is connected to the external load 40, if the switching device 30 is determined not to have failed based on the above mechanism, the judgment circuit 20 can further determine whether the external load 40 has failed based on the current sampling signal transmitted by the current sampling circuit 70.

[0087] In practical implementation, assuming that the switching device 30 is not faulty, if the external load 40 is connected to the circuit, a high-level control signal can be provided to turn on the switching device 30. Theoretically, the magnitude of the current sample value (the current flowing through the external load 40) should be within a set normal threshold range. If the current sample value exceeds the normal threshold range, it indicates that the impedance in the circuit is too low, meaning the external load 40 is not in a connected circuit, and a short-circuit fault can be determined. If the current sample value is within the normal threshold range, the external load 40 can be determined to be working normally. If the current sample value is 0, meaning the entire circuit is not actually connected, an open-circuit fault can be determined.

[0088] In addition, to achieve the above objectives, this application also proposes a motor controller, which includes the load power supply circuit as described above.

[0089] The motor controller proposed in this application employs all embodiments of the load power supply circuit described above, and can solve the technical problem of how to determine whether a switching device has malfunctioned when no external load is connected. Since the motor controller of this application has all the technical features of all embodiments of the load power supply circuit described above, other beneficial effects of the motor controller provided in this application should also be the same as the beneficial effects of the load power supply circuit provided in the above embodiments, and the other technical features of the motor controller are the same as those disclosed in the above embodiments, and will not be repeated here.

[0090] In addition, to achieve the above objectives, this application also proposes a power control module, which includes the load power supply circuit as described above.

[0091] The power control module proposed in this application employs all embodiments of the load power supply circuit described above, and can solve the technical problem of how to determine whether a switching device has malfunctioned when no external load is connected. Since the power control module of this application has all the technical features of all embodiments of the load power supply circuit described above, other beneficial effects of the power control module provided in this application should also be the same as the beneficial effects of the load power supply circuit provided in the above embodiments, and the other technical features of the power control module are the same as those disclosed in the above embodiments, and will not be repeated here.

[0092] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent scope of this application.

Claims

1. A load power supply circuit, characterized in that, The load power supply circuit includes: a voltage sampling circuit, a switching device, and a judgment circuit; The input terminal of the voltage sampling circuit is connected to the first load interface and the first terminal of the switching device, and the output terminal of the voltage sampling circuit is connected to the first input terminal of the judgment circuit; the voltage sampling circuit is used to collect the interface voltage at the first load interface and output the corresponding voltage sampling signal to the judgment circuit. The second terminal of the switching device is connected to the negative terminal of the load power supply, and the second load interface is connected to the positive terminal of the load power supply; the first load interface and the second load interface are used to connect to an external load. The judgment circuit is used to determine whether the switching device is faulty based on the control signal of the switching device and the voltage sampling signal.

2. The load power supply circuit as described in claim 1, characterized in that, The voltage sampling circuit includes: an optocoupler and a first resistor; The primary anode of the optocoupler is connected to a first power supply, the primary cathode of the optocoupler is connected to the first load interface, the secondary first terminal of the optocoupler is connected to the second terminal of the first resistor and the external load of the first input terminal of the judgment circuit, and the secondary second terminal of the optocoupler is grounded; the first terminal of the first resistor is connected to a second power supply.

3. The load power supply circuit as described in claim 2, characterized in that, The load power supply circuit further includes: a unidirectional conduction circuit; The input terminal of the unidirectional conduction circuit is connected to the first power supply, and the output terminal of the unidirectional conduction circuit is connected to the primary anode of the optocoupler. The unidirectional conduction circuit is used to prevent the interface voltage from flowing back to the first power supply.

4. The load power supply circuit as described in claim 3, characterized in that, The unidirectional conduction circuit includes: a first diode; The anode of the first diode is connected to the first power supply, and the cathode of the first diode is connected to the primary anode of the optocoupler.

5. The load power supply circuit as described in claim 2, characterized in that, The load power supply circuit further includes: a first current limiting circuit; The first end of the first current limiting circuit is connected to the first power supply, and the second end of the first current limiting circuit is connected to the primary anode of the optocoupler. The first current limiting circuit is used to limit the current output to the voltage sampling circuit to not exceed a first current threshold.

6. The load power supply circuit as described in claim 5, characterized in that, The first current limiting circuit includes: a second resistor; The first end of the second resistor is connected to the first power supply, and the second end of the second resistor is connected to the primary anode of the optocoupler.

7. The load power supply circuit as described in claim 1, characterized in that, The load power supply circuit further includes: a second diode; The positive terminal of the second diode is connected to the first load interface, and the positive terminal of the second diode is connected to the second load interface.

8. The load power supply circuit as described in claim 1, characterized in that, The load power supply circuit also includes: a third resistor; The first end of the third resistor is connected to the negative terminal of the load power supply, and the second end of the third resistor is connected to the second terminal of the switching device.

9. The load power supply circuit as described in claim 8, characterized in that, The load power supply circuit further includes: a current sampling circuit; The first input terminal of the current sampling circuit is connected to the first terminal of the third resistor, the second input terminal of the current sampling circuit is connected to the second terminal of the third resistor, and the output terminal of the current sampling circuit is connected to the second input terminal of the judgment circuit. The current sampling circuit is used to collect the current flowing through the third resistor and output the corresponding current sampling signal to the judgment circuit. The judgment circuit is also used to determine whether the external load is faulty based on the current sampling signal.

10. A motor controller, characterized in that, Includes the load power supply circuit as described in any one of claims 1-9.

11. A power control module, characterized in that, Includes the load power supply circuit as described in any one of claims 1-9.

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