Power supply driving circuit of BLDC motor

Abstract

The utility model relates to the technical field of BLDC motors, and discloses a power supply drive circuit of a BLDC motor, which comprises a power management module, a transformer, a voltage clamping module, a control module and an isolation drive module. The transformer is provided with a primary winding; the power management module is connected with the primary winding, the voltage clamping module is connected with the primary winding, the voltage clamping module is connected with the isolation driving module, the isolation driving module is connected with the BLDC motor, and the isolation driving module is connected with the control module; the voltage clamping module limits power supply voltage output by the primary winding and outputs driving voltage to the isolation driving module; and the isolation driving module receives the driving signal output by the control module and supplies the driving voltage to the BLDC motor. The voltage clamping module is used for clamping power supply voltage output by the primary winding; the isolation driving module controls the supply and turn-off of the driving voltage through the signal output by the control module so as to control the standby power consumption of the BLDC motor, and the circuit is simplified to the maximum extent.

Description

Technical Field

[0001] The utility model relates to the technical field of BLDC motor control and protection, and particularly relates to a power supply driving circuit for a BLDC motor. Background Art

[0002] Due to the complexity of the control mode and application mode of a BLDC (brushless direct current) motor, and the parameters such as the rotation speed and torque of the motor are also affected by the input power supply, most of them drive the BLDC motor by controlling the input power supply of the motor through a controller.

[0003] However, in the prior art, the power supply circuit supplied to the BLDC motor is too complex, resulting in a large occupied area on the PCBA (printed circuit board), and a high standby power consumption when the BLDC motor is in standby. Summary of the Utility Model

[0004] The main purpose of the embodiment of the present application is to provide a power supply driving circuit for a BLDC motor, so as to simplify the power supply driving circuit of the BLDC motor and control the standby power consumption of the BLDC motor.

[0005] To achieve the above purpose, the embodiment of the present application provides a power supply driving circuit for a BLDC motor, including: a power management module, a transformer, a voltage clamping module, a control module, and an isolation driving module;

[0006] The transformer is provided with a primary winding;

[0007] The power management module is used to connect with an external AC power supply, the output end of the power management module is connected to the primary winding, the input end of the voltage clamping module is connected to the primary winding, the output end of the voltage clamping module is connected to the input end of the isolation driving module, the output end of the isolation driving module is connected to the BLDC motor to be driven, and the driving end of the isolation driving module is connected to the output end of the control module;

[0008] The voltage clamping module is used to limit the power supply voltage output by the primary winding and output a driving voltage to the isolation driving module;

[0009] The isolation driving module is used to receive the driving signal output by the control module and supply the driving voltage to the BLDC motor to be driven.

[0010] Further, the isolation driving module includes: an optocoupler isolation circuit and a field effect transistor;

[0011] The input end of the optocoupler isolation circuit is connected to the output end of the control module, the output end of the optocoupler isolation circuit is connected to the gate of the field effect transistor, and the optocoupler isolation circuit is used to receive the drive signal and turn on the field effect transistor;

[0012] The drain of the field effect transistor is connected to the output end of the voltage clamping module, the source of the field effect transistor is connected to the BLDC motor to be driven, and the field effect transistor is used to supply the drive voltage to the BLDC motor to be driven.

[0013] Further, the voltage clamping module includes: a zener diode, a first diode, a second diode, a first electrolytic capacitor and a second electrolytic capacitor;

[0014] The anodes of the first diode and the second diode are both connected to the primary winding, the cathode of the second diode is connected to the cathode of the zener diode, the anode of the zener diode is connected to the positive electrode of the first electrolytic capacitor, the cathodes of the first diode and the positive electrode of the second electrolytic capacitor are both connected to the input end of the isolation drive module, and the negative electrodes of the first electrolytic capacitor and the second electrolytic capacitor are both grounded.

[0015] Further, the power management module includes: a rectifying and filtering circuit and a switching power supply circuit;

[0016] The output end of the rectifying and filtering circuit is connected to the input end of the switching power supply circuit, the output end of the switching power supply circuit is connected to the primary winding, and the rectifying and filtering circuit is used to connect to an external AC power supply.

[0017] Further, the rectifying and filtering circuit includes: a first series resistor group, a common mode inductor, a thermistor, a rectifier, a first capacitor, a second capacitor, a third diode, a fourth diode and a third electrolytic capacitor;

[0018] The first capacitor is connected in parallel with the first series resistor group, the first series resistor group is connected to the input end of the common mode inductor, the output end of the common mode inductor is connected to the second capacitor, one end of the second capacitor is connected to the input end of the rectifier through the thermistor, the other end of the second capacitor is connected to the input end of the rectifier, the output end of the rectifier is connected to the anode of the third diode, the cathode of the third diode is respectively connected to the positive electrode of the third electrolytic capacitor and the anode of the fourth diode, the cathode of the fourth diode is connected to the input end of the switching power supply circuit, and the negative electrode of the third electrolytic capacitor is grounded.

[0019] Further, the switching power supply circuit includes: a switching power supply chip, a second series resistor group, a parallel resistor group and an RC parallel circuit;

[0020] One end of the second series resistor group is connected to the output end of the rectifying and filtering circuit, the other end of the second series resistor group is connected to the first pin of the switching power supply chip, the second pin of the switching power supply chip is used to be connected to an external DC power supply, the third pin of the switching power supply chip is grounded, the fourth pin of the switching power supply chip is connected to one end of the parallel resistor group, and the other end of the parallel resistor group is grounded;

[0021] The fifth pin of the switching power supply chip is connected to one end of the RC parallel circuit, the other end of the RC parallel circuit is grounded, and both the seventh pin and the eighth pin of the switching power supply chip are connected to the primary winding.

[0022] Furthermore, the switching power supply circuit further includes: a current limiting circuit and a filtering circuit;

[0023] The input end of the current limiting circuit is connected to the primary winding, the output end of the current limiting circuit is connected to the input end of the filtering circuit, the input end of the filtering circuit is further connected to one end of the second series resistor group, and the output end of the filtering circuit is connected to the primary winding.

[0024] Furthermore, the transformer is further provided with a secondary winding.

[0025] Furthermore, it further includes: a power supply circuit;

[0026] The power supply circuit is connected to the secondary winding, and the power supply circuit is used to receive the power supply voltage output by the secondary winding and output a supply DC voltage.

[0027] Furthermore, the switching power supply chip is an LC1210 switching power supply chip.

[0028] The beneficial effects of the present utility model are as follows: The power management module is connected to the voltage clamping module through the primary winding of the transformer, the voltage output by the power management module is output through the primary winding of the transformer, and the voltage clamping module clamps the power supply voltage output by the primary winding, so as to obtain the driving voltage for driving the BLDC motor; The isolation driving module controls the supply and cut-off of the driving voltage by receiving the signal output by the control module, so as to obtain the effect of controlling the standby power consumption as required. At the same time, the circuit is simplified to the greatest extent, the cost is saved, and the occupied area on the PCBA is reduced. Description of the Drawings

[0029] Figure 1 It is a partial circuit schematic diagram of a power supply driving circuit for a BLDC motor provided by an embodiment of the present utility model;

[0030] Figure 2It is a partial circuit schematic diagram of a power supply driving circuit for a BLDC motor provided by another embodiment of the present utility model;

[0031] Figure 3 It is a schematic diagram of the power supply circuit of a BLDC motor in the prior art. Specific embodiments

[0032] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and cannot be construed as a limitation to the present utility model.

[0033] It should be noted that although the functional modules are divided in the schematic diagram, in some cases, it may be different from the module division in the system.

[0034] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more features.

[0035] In the description of the present utility model, it should be noted that unless otherwise clearly defined, words such as "set", "installed", and "connected" should be understood in a broad sense. Those skilled in the art can reasonably determine the specific meanings of the above words in the present utility model in combination with the specific content of the technical solution.

[0036] A BLDC motor, fully known as a BrushLess Direct Current Motor, is a motor that uses an electronic commutation device to replace the mechanical commutator and brushes in a traditional DC motor.

[0037] Printed circuit board, (PCBA Printed Circuit Board Assembly).

[0038] In the prior art, referring to Figure 3 , the power supply circuit supplied to the BLDC motor is too complex. The 7815 voltage regulator is still required to regulate the output voltage, and there is no regulation for the driving voltage supplied to the BLDC motor. Therefore, it occupies a large area on the PCBA (printed circuit board), and the standby power consumption when controlling the BLDC motor to standby is relatively high.

[0039] Referring to Figures 1 to 2 , in some embodiments of the present utility model, the power supply driving circuit of the BLDC motor includes: a control module 400, an isolation driving module 300, a voltage clamping module 200, a transformer T1, and a power management module 100.

[0040] The transformer T1 is provided with a secondary winding and a primary winding. The primary winding is provided with a first pin, a second pin, a third pin, a fourth pin, and a fifth pin.

[0041] The external AC power supply is electrically connected to the input end of the power management module 100. The output end of the power management module 100 is electrically connected to the primary winding. The power management module 100 receives the external AC voltage, rectifies and filters the external AC voltage, and outputs a first voltage to the transformer T1.

[0042] In the transformer T1, the primary winding processes the first voltage and outputs a power supply voltage to the voltage clamping module 200.

[0043] The input end of the voltage clamping module 200 is electrically connected to the fifth pin of the primary winding. The output end of the voltage clamping module 200 is electrically connected to the input end of the isolation driving module 300. The voltage clamping module 200 is used to receive the power supply voltage output from the fifth pin of the primary winding, limit the power supply voltage, and thus output a driving voltage to the isolation driving module 300. Among them, the driving voltage is a 15V DC voltage.

[0044] The input end of the isolation driving module 300 is electrically connected to the output end of the voltage clamping module 200. The output end of the isolation driving module 300 is electrically connected to the BLDC motor to be driven. The driving end of the isolation driving module 300 is electrically connected to the output end of the control module 400.

[0045] In an embodiment, the control module 400 outputs a driving signal. The isolation driving module 300 receives the driving signal. The isolation driving module 300 inputs the driving voltage to the BLDC motor to be driven to realize the operation of driving the BLDC motor. Among them, the driving signal is a low-level signal.

[0046] In an embodiment, the control module 400 outputs a cut-off signal. The isolation driving module 300 receives the cut-off signal. The isolation driving module 300 stops supplying the driving voltage to the BLDC motor to be driven, and the BLDC motor enters the standby state to reduce the standby power consumption of the BLDC motor. Among them, the cut-off signal is a high-level signal.

[0047] Compared with the prior art, the present application directly obtains the driving voltage from the voltage clamping module 200 connected to the primary winding, reducing the power consumption of the voltage stabilizing circuit provided. The power management module 100 is connected to the voltage clamping module 200 through the primary winding of the transformer T1. The switching power supply output by the power management module 100 is output through the primary winding of the transformer T1. The voltage clamping module 200 clamps the power supply voltage output by the primary winding, thereby obtaining the driving voltage for driving the BLDC motor. The isolation driving module 300 controls the supply and cut-off of the driving voltage by receiving the signal output by the control module 400, thereby achieving the effect of controlling the standby power consumption as required. At the same time, the circuit is simplified to the greatest extent, the cost is saved, and the occupied area on the PCBA is reduced.

[0048] Referring to Figures 1 to 2 , in some embodiments of the present utility model, the power management module 100 includes: a switching power supply circuit 120 and a rectifying and filtering circuit 110.

[0049] The external AC power supply is electrically connected to the input end of the rectifying and filtering circuit 110. The output end of the rectifying and filtering circuit 110 is electrically connected to the input end of the switching power supply circuit 120. The rectifying and filtering circuit 110 can receive the external AC voltage, perform rectifying and filtering processing on the external AC voltage, and output a second voltage.

[0050] The rectifying and filtering circuit 110 includes: a first capacitor C1, a first series resistor group, a common mode inductor L1, a second capacitor C2, a thermistor NTC, a rectifier BD1, a third diode D3, a fourth diode D4, and a third electrolytic capacitor CE3.

[0051] Both ends of the first capacitor C1 are electrically connected to the external AC power supply. The first capacitor C1 is connected in parallel with the first series resistor group. One end of the first series resistor group is electrically connected to the third pin of the common mode inductor L1, and the other end of the first series resistor group is electrically connected to the first pin of the common mode inductor L1.

[0052] Among them, the first series resistor group is formed by connecting a first resistor R1, a second resistor R2, and a third resistor R3 in series.

[0053] The second pin of the common mode inductor L1 is electrically connected to one end of the second capacitor C2. The fourth pin of the common mode inductor L1 is electrically connected to the other end of the second capacitor C2 and one end of the thermistor NTC. The other end of the thermistor NTC is electrically connected to the second pin of the rectifier BD1. One end of the second capacitor C2 is electrically connected to the first pin of the rectifier BD1. The fourth pin of the rectifier BD1 is grounded. Among them, the rectifier BD1 is a bridge rectifier.

[0054] In one embodiment, a thermistor NTC is used to detect the temperature in a circuit. When the circuit temperature is too high, the resistance value of the thermistor NTC will rapidly decrease, thereby protecting the circuit.

[0055] The anode of the third diode D3 is electrically connected to the third pin of the rectifier BD1. The cathode of the third diode D3 is electrically connected to the positive electrode of the third electrolytic capacitor CE3. The negative electrode of the third electrolytic capacitor CE3 is grounded. The cathode of the third diode D3 is electrically connected to the anode of the fourth diode D4. The cathode of the fourth diode D4 is electrically connected to the input end of the switching power supply circuit 120.

[0056] The output end of the switching power supply circuit 120 is electrically connected to the primary winding. The switching power supply circuit 120 can receive a second voltage and output a first voltage to the transformer T1.

[0057] The switching power supply circuit 120 includes: a second series resistor group, a switching power supply chip U2, a parallel resistor group, a filtering circuit, an RC parallel circuit, and a current limiting circuit. Among them, the model of the switching power supply chip U2 is the LC1210 chip.

[0058] The first pin of the switching power supply chip U2 is electrically connected to the cathode of the fourth diode D4 through the second series resistor group.

[0059] Among them, the second series resistor group is formed by the series connection of the fourth resistor R4 and the fifth resistor R5. That is to say, one end of the fourth resistor R4 is electrically connected to the cathode of the fourth diode D4, one end of the fifth resistor R5 is electrically connected to the other end of the fourth resistor R4, and the other end of the fifth resistor R5 is electrically connected to the first pin of the switching power supply chip U2.

[0060] The second pin of the switching power supply chip U2 is electrically connected to an external DC power supply. The third pin of the switching power supply chip U2 is electrically connected to one end of the parallel resistor group. The other end of the parallel resistor group is grounded. The third pin of the switching power supply chip U2 is grounded.

[0061] Among them, the parallel resistor group is formed by the parallel connection of the sixth resistor R6 and the seventh resistor R7. That is to say, one end of the sixth resistor R6 is electrically connected to the fourth pin of the switching power supply chip U2, the other end of the sixth resistor R6 is grounded, one end of the seventh resistor R7 is electrically connected to the fourth pin of the switching power supply chip U2, and the other end of the seventh resistor R7 is grounded.

[0062] The fifth pin of the switching power supply chip U2 is electrically connected to one end of the RC parallel circuit. The other end of the RC parallel circuit is grounded.

[0063] Among them, the RC parallel circuit includes: the eleventh resistor R11 and the fourth capacitor C4, and the eleventh resistor R11 is in parallel with the fourth capacitor C4. That is to say, one end of the eleventh resistor R11 is electrically connected to the fifth pin of the switching power supply chip U2, and the other end of the eleventh resistor R11 is grounded; one end of the fourth capacitor C4 is electrically connected to the fifth pin of the switching power supply chip U2, and the other end of the fourth capacitor C4 is grounded.

[0064] The seventh pin of the switching power supply chip U2 is electrically connected to the eighth pin of the switching power supply chip U2, and the eighth pin of the switching power supply chip U2 is electrically connected to the third pin of the primary winding of the transformer T1.

[0065] The input end of the current limiting circuit is electrically connected to the eighth pin of the switching power supply chip U2, the output end of the current limiting circuit is electrically connected to the input end of the filtering circuit, and the output end of the filtering circuit is electrically connected to the first pin of the primary winding.

[0066] Among them, the filtering circuit includes: the eighth resistor R8, the ninth resistor R9 and the third capacitor C3.

[0067] The eighth resistor R8, the ninth resistor R9 and the third capacitor C3 are in parallel with each other. That is to say, one end of the third capacitor C3 is electrically connected to one end of the fourth resistor R4 and one end of the eighth resistor R8 respectively, and the other end of the third capacitor C3 is electrically connected to the other end of the tenth resistor R10 and the other end of the eighth resistor R8 respectively. One end of the ninth resistor R9 is electrically connected to one end of the eighth resistor R8 and the first pin of the primary winding respectively, and the other end of the ninth resistor R9 is electrically connected to the other end of the eighth resistor R8.

[0068] Among them, the current limiting circuit includes: the tenth resistor R10 and the fifth diode D5.

[0069] The anode of the fifth diode D5 is electrically connected to the third pin of the primary winding and the eighth pin of the switching power supply chip U2 respectively, the cathode of the fifth diode D5 is electrically connected to one end of the tenth resistor R10, and the other end of the tenth resistor R10 is electrically connected to the other end of the third capacitor C3 and the other end of the eighth resistor R8 respectively.

[0070] Refer to Figures 1 to 2 , in some embodiments of the present invention, the voltage clamping module 200 includes: the second electrolytic capacitor CE2, the first diode D1, the first electrolytic capacitor CE1, the second diode D2 and the zener diode DZ1.

[0071] The fifth pin of the primary winding is electrically connected to the anode of the first diode D1, and the cathode of the first diode D1 is electrically connected to the positive electrode of the second electrolytic capacitor CE2. Among them, the fourth pin of the primary winding is grounded, and the second pin of the primary winding is suspended.

[0072] The negative electrode of the second electrolytic capacitor CE2 is grounded, and the cathode of the first diode D1 and the positive electrode of the second electrolytic capacitor CE2 are both electrically connected to the input end of the isolation driving module 300.

[0073] The fifth pin of the primary winding is electrically connected to the anode of the second diode D2, the cathode of the second diode D2 is electrically connected to the cathode of the voltage stabilizing diode DZ1, and the anode of the voltage stabilizing diode DZ1 is electrically connected to an external DC power supply.

[0074] The anode of the voltage stabilizing diode DZ1 is electrically connected to the positive electrode of the first electrolytic capacitor CE1, the positive electrode of the first electrolytic capacitor CE1 is also electrically connected to an external DC power supply, and the negative electrode of the first electrolytic capacitor CE1 is grounded.

[0075] In this embodiment, the switching power supply circuit 120 outputs a power supply voltage through the primary winding of the transformer T1, and the voltage stabilizing diode DZ1 is set for clamping, so as to obtain the required output power supply voltage, that is, the driving voltage of the BLDC motor.

[0076] Among them, during operation, the parameters of the voltage stabilizing diode DZ1 and the algorithm parameters can be adjusted according to specific application scenarios to optimize the measurement performance. In one embodiment, according to the operating temperature of the current circuit, the voltage data of the voltage stabilizing diode DZ1 during operation, and the voltage data of the first voltage output by the switching power supply circuit 120, the parameters of the voltage stabilizing diode DZ1 and the parameters of the primary winding are adjusted to adjust the driving voltage input to the BLDC motor.

[0077] Specifically, according to the operating temperature of the current circuit, the voltage data of the voltage stabilizing diode DZ1 during operation, and the voltage data of the first voltage, it is judged whether the voltage stabilizing diode DZ1 has a voltage drift. If so, the compensation circuit is turned on. The compensation circuit is electrically connected to the voltage clamping module to compensate or adjust the voltage drift caused by temperature change until it is determined that the voltage stabilizing diode DZ1 does not have a voltage drift, and the compensation circuit is cut off.

[0078] Specifically, according to the voltage data of the voltage stabilizing diode DZ1 during operation and the voltage data of the first voltage, it is judged whether the driving voltage is the driving voltage required by the BLDC motor. If not, the parameters of the primary winding are adjusted to adjust the driving voltage input to the BLDC motor.

[0079] Compared with the prior art, the present application directly obtains the driving voltage from the voltage clamping module 200 connected to the primary winding, reducing the power consumption of the set voltage stabilizing circuit. The power management module 100 is connected to the voltage clamping module 200 through the primary winding of the transformer T1. The switching power supply output by the power management module 100 is output through the primary winding of the transformer T1, and the voltage clamping module 200 clamps the power supply voltage output by the primary winding, so as to obtain the driving voltage for driving the BLDC motor.

[0080] Reference Figures 1 to 2 , in some embodiments of the present utility model, the isolation drive module 300 includes: a fourteenth resistor R14, a fifth capacitor C5, an optocoupler isolation circuit 310, a fifteenth resistor R15, a fourth electrolytic capacitor CE4, a sixth capacitor C6, and a field effect transistor M1.

[0081] The input end of the optocoupler isolation circuit 310 is electrically connected to the output end of the control module 400, so that the drive end of the isolation drive module 300 is connected to the control module 400. The output end of the optocoupler isolation circuit 310 is electrically connected to the gate of the field effect transistor M1.

[0082] Among them, the optocoupler isolation circuit 310 includes: an optocoupler isolation chip U1, a twelfth resistor R12, and a thirteenth resistor R13.

[0083] The first pin of the optocoupler isolation chip U1 is electrically connected to an external DC power supply. The second pin of the optocoupler isolation chip U1 is electrically connected to the control module 400 through the twelfth resistor R12. The third pin of the optocoupler isolation chip U1 is grounded. The fourth pin of the optocoupler isolation chip U1 is electrically connected to the gate of the field effect transistor M1 and one end of the fifteenth resistor R15 through the thirteenth resistor R13. The other end of the fifteenth resistor R15 is electrically connected to the drain of the field effect transistor M1.

[0084] The drain of the field effect transistor M1 is electrically connected to the cathode of the first diode D1. The fifth capacitor C5 and the fourteenth resistor R14 are in parallel. One end of the fifth capacitor C5 and one end of the fourteenth resistor R14 are both electrically connected to the drain of the field effect transistor M1. The other end of the fifth capacitor C5 and the other end of the fourteenth resistor R14 are both grounded.

[0085] The source of the field effect transistor M1 is electrically connected to the BLDC motor to be driven. The sixth capacitor C6 and the fourth electrolytic capacitor CE4 are in parallel. One end of the sixth capacitor C6 and the positive electrode of the fourth electrolytic capacitor CE4 are both electrically connected to the BLDC motor to be driven. The other end of the sixth capacitor C6 and the negative electrode of the fourth electrolytic capacitor CE4 are both grounded.

[0086] In one embodiment, the control module 400 outputs a drive signal, the optocoupler isolation chip U1 is turned on, the field effect transistor M1 is turned on, and the drive voltage is input to the BLDC motor to be driven, so as to drive the BLDC motor to operate. Among them, the drive signal is a low-level signal.

[0087] In one embodiment, the control module 400 outputs a cut-off signal, the optocoupler isolation chip is cut off, the field effect transistor M1 is cut off, the drive voltage is not applied to the BLDC motor to be driven, and the BLDC motor enters the standby state to reduce the standby power consumption of the BLDC motor. Among them, the cut-off signal is a high-level signal.

[0088] The isolation drive module 300 controls the supply and cut-off of the drive voltage by receiving the signal output by the control module 400, so as to achieve the effect of controlling the standby power consumption as required. At the same time, the circuit is simplified to the greatest extent, the cost is saved, and the occupied area on the PCBA is reduced.

[0089] Referring to Figures 1 to 2 , in some embodiments of the present invention, the power supply drive circuit further includes: a power supply circuit 500.

[0090] The input end of the power supply circuit 500 is electrically connected to the secondary winding. The power supply circuit 500 can perform voltage stabilization and filtering processing on the power supply voltage output by the secondary winding, so as to output a supply DC voltage. Among them, the supply DC voltage is a 12V DC voltage for supplying power to other devices in the product.

[0091] Compared with the prior art, the present application directly obtains the drive voltage from the voltage clamping module 200 connected to the primary winding, reducing the power consumption of the set voltage stabilization circuit. The power management module 100 is connected to the voltage clamping module 200 through the primary winding of the transformer T1. The switching power supply output by the power management module 100 is output through the primary winding of the transformer T1. The voltage clamping module 200 clamps the power supply voltage output by the primary winding to obtain the drive voltage for driving the BLDC motor; the isolation drive module 300 controls the supply and cut-off of the drive voltage by receiving the signal output by the control module 400, so as to achieve the effect of controlling the standby power consumption as required. At the same time, the circuit is simplified to the greatest extent, the cost is saved, and the occupied area on the PCBA is reduced.

[0092] The above has specifically described the preferred embodiments of the present invention, but the present invention is not limited to the described embodiments. Those skilled in the art can also make various equivalent variations or substitutions without departing from the spirit of the present invention, and these equivalent variations or substitutions are all included within the scope defined by the claims of this application.

Claims

1. A power supply driving circuit for a BLDC motor, characterized in that: include: Power management module, transformer, voltage clamp module, control module and isolation drive module; The transformer is provided with a primary winding; The power management module is used to connect to an external AC power supply, the output end of the power management module is connected to the primary winding, the input end of the voltage clamping module is connected to the primary winding, the output end of the voltage clamping module is connected to the input end of the isolation driving module, the output end of the isolation driving module is connected to the BLDC motor to be driven, and the driving end of the isolation driving module is connected to the output end of the control module; The voltage clamping module is used to limit the power supply voltage output by the primary winding and output the driving voltage to the isolation driving module; The isolation driving module is used to receive the driving signal output by the control module and supply the driving voltage to the BLDC motor to be driven.

2. The power supply driving circuit of a BLDC motor according to claim 1, characterized in that: The isolation driving module includes: an optocoupler isolation circuit and a field effect transistor; The input end of the optocoupler isolation circuit is connected to the output end of the control module, the output end of the optocoupler isolation circuit is connected to the gate of the field effect tube, and the optocoupler isolation circuit is used to receive the driving signal and turn on the field effect tube; The drain of the field effect tube is connected to the output end of the voltage clamping module, the source of the field effect tube is connected to the BLDC motor to be driven, and the field effect tube is used to supply the driving voltage to the BLDC motor to be driven.

3. The power supply driving circuit of a BLDC motor according to claim 1, characterized in that: The voltage clamping module includes: a voltage stabilizing diode, a first diode, a second diode, a first electrolytic capacitor and a second electrolytic capacitor; The anode of the first diode and the anode of the second diode are both connected to the primary winding, the cathode of the second diode is connected to the cathode of the voltage regulator diode, the anode of the voltage regulator diode is connected to the positive electrode of the first electrolytic capacitor, the cathode of the first diode and the positive electrode of the second electrolytic capacitor are both connected to the input end of the isolation drive module, and the negative electrode of the first electrolytic capacitor and the negative electrode of the second electrolytic capacitor are both grounded.

4. The power supply driving circuit of a BLDC motor according to claim 1, characterized in that: The power management module includes: a rectifier filter circuit and a switch power supply circuit; The output end of the rectifying and filtering circuit is connected to the input end of the switching power supply circuit, the output end of the switching power supply circuit is connected to the primary winding, and the rectifying and filtering circuit is used to be connected to an external AC power supply.

5. The power supply driving circuit of a BLDC motor according to claim 4, characterized in that: The rectification and filtering circuit comprises: a first series resistor group, a common mode inductor, a thermistor, a rectifier, a first capacitor, a second capacitor, a third diode, a fourth diode and a third electrolytic capacitor; The first capacitor is connected in parallel with the first series resistor group, the first series resistor group is connected to the input end of the common-mode inductor, the output end of the common-mode inductor is connected to the second capacitor, one end of the second capacitor is connected to the input end of the rectifier through the thermistor, the other end of the second capacitor is connected to the input end of the rectifier, the output end of the rectifier is connected to the anode of the third diode, the cathode of the third diode is respectively connected to the positive electrode of the third electrolytic capacitor and the anode of the fourth diode, the cathode of the fourth diode is connected to the input end of the switching power supply circuit, and the negative electrode of the third electrolytic capacitor is grounded.

6. The power supply driving circuit of a BLDC motor according to claim 4, characterized in that: The switching power supply circuit comprises: a switching power supply chip, a second series resistor group, a parallel resistor group and an RC parallel circuit; One end of the second series resistor group is connected to the output end of the rectifier filter circuit, the other end of the second series resistor group is connected to the first pin of the switching power chip, the second pin of the switching power chip is used to connect to an external DC power supply, the third pin of the switching power chip is grounded, the fourth pin of the switching power chip is connected to one end of the parallel resistor group, and the other end of the parallel resistor group is grounded; The fifth pin of the switching power chip is connected to one end of the RC parallel circuit, the other end of the RC parallel circuit is grounded, and the seventh pin and the eighth pin of the switching power chip are both connected to the primary winding.

7. The power supply driving circuit of a BLDC motor according to claim 6, characterized in that: The switching power supply circuit also includes: a current limiting circuit and a filtering circuit; The input end of the current limiting circuit is connected to the primary winding, the output end of the current limiting circuit is connected to the input end of the filter circuit, the input end of the filter circuit is also connected to one end of the second series resistor group, and the output end of the filter circuit is connected to the primary winding.

8. The power supply driving circuit of a BLDC motor according to claim 1, characterized in that: The transformer is also provided with a secondary winding.

9. The power supply driving circuit of a BLDC motor according to claim 8, characterized in that: Also includes: Power supply circuit; The power supply circuit is connected to the secondary winding, and is used to receive the power supply voltage output by the secondary winding and output a power supply DC voltage.

10. The power supply driving circuit of a BLDC motor according to claim 6, characterized in that: The switching power supply chip is an LC1210 switching power supply chip.

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