Motor controller, motor, and clothes processing device

Abstract

The present invention provides a motor controller, a motor, and a clothing processing device. The motor controller includes: a DC bus; a rectifier circuit for converting the AC voltage output by an AC power supply into a DC voltage to power the DC bus; a control circuit, the control circuit including a capacitor component and a first switch, which controls the first switch to connect the capacitor component to the DC bus to limit the minimum voltage on the DC bus to within a preset range; and an inverter circuit for converting the DC voltage on the DC bus into an AC voltage to control the operating state of the motor connected to the inverter circuit. The motor controller proposed in the technical solution of the present invention can always control the minimum bus voltage of the DC bus to approximately half the amplitude of the AC voltage, thereby avoiding torque pulsation that easily causes unstable speed control when the motor to be controlled has a low speed and a large torque requirement.

Description

Technical Field

[0001] The present invention relates to the technical field of motors, and in particular to a motor controller, a motor, and a clothes processing device. Background Art

[0002] In the prior art, controllers for motors with small busbar capacitors or without electrolytic capacitors have been widely used in household appliances such as air conditioners, water pumps, and washing machines due to their small size, long life, high power factor, and low cost. However, since such controllers do not have large electrolytic capacitor energy storage units on the DC bus, when the motor is running at low speed, they will generate torque pulsations that are integer multiples of the AC power supply voltage frequency, which can easily lead to unstable speed control and noise problems, and in severe cases, can cause the motor controller to malfunction. Therefore, how to provide a technical solution that can prevent the occurrence of torque pulsations and noise caused by controllers for motors with small busbar capacitors or without electrolytic capacitors when controlling the motor at low speed has become a problem that needs to be solved urgently. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

[0004] To this end, a first aspect of the present invention is to provide a controller for a motor.

[0005] A second aspect of the present invention is to provide an electric motor.

[0006] A third aspect of the present invention is to provide a clothes treating device.

[0007] In view of this, according to the first aspect of the present invention, the present invention proposes a controller for a motor, which includes: a DC bus; a rectifier circuit for converting the AC voltage output by an AC power supply into a DC voltage to power the DC bus; a control circuit, the control circuit including a capacitor component and a first switch, and the capacitor component is connected to the DC bus by controlling the first switch to limit the minimum voltage on the DC bus to within a preset range; an inverter circuit for converting the DC voltage on the DC bus into an AC voltage to control the working state of the motor connected to the inverter circuit.

[0008] In this technical solution, the controller of the above-mentioned motor specifically includes a DC bus, which is used to provide DC voltage to the inverter so that the inverter converts the DC voltage into AC voltage to provide AC voltage for the motor to be controlled by the motor controller.

[0009] Furthermore, the motor controller further includes a rectifier circuit. Specifically, the input end of the rectifier circuit is connected to the AC power supply, and the output end of the rectifier circuit is connected to the DC bus. Specifically, when controlling the operation of the controlled motor, the rectifier circuit can obtain AC voltage from the AC power supply, convert the AC voltage into DC voltage, and input it into the DC bus to power the DC bus.

[0010] Furthermore, the controller of the motor further includes a control circuit, specifically, the control circuit being provided with a first switch and a capacitor assembly. Specifically, when the motor to be controlled has a low speed and a high torque demand, the first switch is closed, connecting the capacitor assembly to the DC bus. The capacitor assembly adjusts the power factor on the DC bus by charging or discharging, so that the minimum voltage on the DC bus is always within a preset range.

[0011] It should be noted that the above preset range is generally set to about half of the AC voltage amplitude.

[0012] It can be understood that when the speed of the motor to be controlled is low and the torque demand is large, the motor to be controlled is prone to generate torque pulsation that is an integer multiple of the AC power supply voltage frequency, resulting in the inability to stably control the motor speed. Therefore, when the speed of the motor to be controlled is low and the torque demand is large, it is necessary to adjust the first switch to a closed state to always control the minimum voltage on the DC bus within a preset range, thereby ensuring stable power supply to the motor to avoid torque pulsation when the motor to be controlled is running.

[0013] Specifically, when the speed of the motor to be controlled is high and the output power of the motor is large, the first switch will be in the disconnected state, so that the capacitor component is not connected to the DC bus, and the motor controller is in normal working mode, so that the motor to be controlled can provide greater output power.

[0014] It is understood that when the motor to be controlled has a high speed and a high output power, the motor to be controlled will not generate torque ripples that are integer multiples of the AC power supply voltage frequency. Therefore, when the motor to be controlled has a high speed and a high output power, there is no need to adjust the first switch to a closed state, that is, there is no need to connect the capacitor assembly to the DC bus, so that the motor controller is in a normal operating mode, allowing the motor to provide a higher output power.

[0015] Furthermore, the motor controller includes an inverter circuit. Specifically, the inverter circuit has an input connected to a DC bus, and an output connected to the motor to be controlled. Specifically, when the motor controller controls the motor, the inverter circuit obtains a power-factor-adjusted DC voltage from the DC bus via the capacitor assembly, and converts the obtained DC voltage into an AC voltage to control the operation of the motor to be controlled.

[0016] In this technical solution, a first switch and a capacitor component are provided in the control circuit of the motor controller. When the first switch is closed, the capacitor component can be connected to the DC bus, and the minimum value of the bus voltage of the DC bus can always be controlled to be about half of the AC voltage amplitude, thereby avoiding the situation where torque pulsation easily occurs and the speed control is unstable when the motor to be controlled has a low speed and a large torque requirement. This ensures the stability and reliability of the motor operation when the motor controller controls the operating state of the motor to be controlled, and can also effectively reduce the noise of the motor to be controlled during operation.

[0017] In the above technical solution, the DC bus includes a first bus and a second bus, the capacitor assembly includes a first capacitor and a second capacitor, the first end of the first capacitor is connected to the first bus, and the second end of the second capacitor is connected to the second bus through a first switch; the control circuit also includes: a first diode, the positive electrode of the first diode is connected to the second bus, and the negative electrode of the first diode is connected to the second end of the first capacitor; a second diode, the negative electrode of the second diode is connected to the first bus, and the positive electrode of the second diode is connected to the first end of the second capacitor; a third diode, the positive electrode of the third diode is connected to the second end of the first capacitor, and the negative electrode of the third diode is connected to the first end of the second capacitor.

[0018] In this technical solution, the above-mentioned DC bus specifically includes a first bus and a second bus, wherein the first bus is used to indicate the P bus and the second bus is used to indicate the N bus; the above-mentioned capacitor component specifically includes a first capacitor and a second capacitor, specifically, when the first switch is closed and the first capacitor and the second capacitor are in a charging state, the first capacitor and the second capacitor are connected in series to the above-mentioned DC bus; when the first switch is closed and the first capacitor and the second capacitor are in a discharging state, the first capacitor and the second capacitor are connected in parallel to the above-mentioned DC bus; specifically, the first end of the first capacitor is connected to the P bus (that is, the above-mentioned first bus), and the second end of the second capacitor is connected to the N bus (that is, the above-mentioned second bus).

[0019] Furthermore, the above-mentioned control circuit is also provided with a first diode. Specifically, the positive pole of the first diode is connected to the above-mentioned second bus, and the negative pole of the first diode is connected to the second end of the above-mentioned first capacitor, that is, the first capacitor and the first diode are connected in series between the above-mentioned first bus and the above-mentioned second bus.

[0020] Specifically, when the motor to be controlled is operating normally, the voltage of the first bus is higher than the voltage of the second bus. By setting a diode in reverse between the first bus and the second bus, the first capacitor can be prevented from being directly connected to the above-mentioned DC bus, thereby ensuring that when the motor to be controlled is operating at high speed and high output power, the motor controller is in an operating mode without electrolytic capacitor (i.e., the above-mentioned normal operating mode). In addition, when the first switch is closed, the voltage resonance generated by the first capacitor during discharge can be effectively eliminated by the first diode, thereby ensuring the stability of the operation of the motor to be controlled.

[0021] Furthermore, the above-mentioned control circuit is also provided with a second diode. Specifically, the positive pole of the second diode is connected to the first end of the above-mentioned second capacitor, and the negative pole of the second diode is connected to the above-mentioned first bus, that is, the second capacitor and the second diode are connected in series between the above-mentioned first bus and the above-mentioned second bus.

[0022] Specifically, the voltage of the first bus is higher than the voltage of the second bus. By setting a diode in reverse between the first bus and the second bus, when the first switch is closed, the voltage resonance generated by the second capacitor during discharge can be effectively eliminated, thereby ensuring the stability of the operation of the motor to be controlled.

[0023] Furthermore, the control circuit is also provided with a third diode. Specifically, the anode of the third diode is connected to the second end of the first capacitor, and the cathode of the third diode is connected to the first end of the second capacitor, that is, the first capacitor and the second capacitor are connected in series between the first bus and the second bus through the third diode and the first switch.

[0024] In this technical solution, the capacitor assembly specifically includes a first capacitor and a second capacitor, and the above-mentioned control circuit is provided with a first diode, a second diode and a third diode. When the first switch is closed and the sum of the voltages of the first capacitor and the second capacitor is less than the bus voltage, the first capacitor and the second capacitor are connected in series between the first bus and the second bus through the third diode to charge the first capacitor and the second capacitor. When the first switch is closed and the bus voltage is lower than the voltage of the first capacitor or the bus voltage is lower than the voltage of the second capacitor, the first capacitor and the second capacitor are connected to the DC bus through the first diode and the second diode respectively, and the first capacitor and the second capacitor are in parallel state, and the first capacitor and the second capacitor discharge to the DC bus. Through the above-mentioned technical solution, the present invention can control the minimum value of the bus voltage to about half of the AC voltage amplitude, reduce the torque pulsation during the operation of the motor to be controlled, reduce the speed fluctuation of the motor to be controlled, and reduce the noise during the operation of the motor to be controlled.

[0025] In the above technical solution, the first end of the first switch is connected to the second end of the second capacitor, and the second end of the first switch is connected to the second bus.

[0026] In this technical solution, the first end of the first switch is connected to the second end of the second capacitor, and the second end of the first switch is connected to the second bus, that is, the first switch is connected between the second capacitor and the second bus.

[0027] In some embodiments, the first end of the first switch may be connected to the anode of the second diode, and the second end of the first switch may be connected to the first end of the second capacitor, that is, the first switch may be connected in series between the second diode and the second capacitor.

[0028] In some embodiments, the first end of the first switch may be connected to the cathode of the third diode, and the second end of the first switch may be connected to the first end of the second capacitor, that is, the first switch may be connected in series between the third diode and the second capacitor.

[0029] In some embodiments, the first end of the first switch may be connected to the second end of the first capacitor, and the second end of the first switch may be connected to the anode of the third diode, that is, the first switch may be connected in series between the first capacitor and the third diode.

[0030] In some embodiments, the first end of the first switch may be connected to the second end of the first capacitor, and the second end of the first switch may be connected to the cathode of the first diode, that is, the first switch may be connected in series between the first capacitor and the first diode.

[0031] In some embodiments, the first end of the first switch may be connected to the first bus, and the second end of the first switch may be connected to the first end of the first capacitor, that is, the first switch may be connected in series between the first bus and the first capacitor.

[0032] In some embodiments, the first end of the first switch can also be connected to the cathode of the first diode and the second end of the second capacitor, and the second end of the first switch can be connected to the second bus, that is, the first switch can be connected in series between the common end of the second capacitor and the first diode and the second bus.

[0033] In some embodiments, the first end of the first switch can be connected to the above-mentioned first bus, and the second end of the first switch can be connected to the first end of the above-mentioned first capacitor and the negative electrode of the above-mentioned second diode, that is, the first switch can be connected in series between the common end of the first capacitor and the second diode and the first bus.

[0034] In this technical solution, by connecting the first switch between the second capacitor and the second bus, the technical solution of the present invention can connect the above-mentioned first capacitor and the above-mentioned second capacitor to the DC bus when the first switch is closed, so as to control the minimum value of the bus voltage to about half of the AC voltage amplitude.

[0035] In the above technical solution, when the first switch is closed and the first capacitor and the second capacitor are in a charging state, the first capacitor and the second capacitor are connected in series to the first bus and the second bus through the third diode; or when the first switch is closed and the first capacitor and the second capacitor are in a discharging state, the first capacitor is connected to the first bus and the second bus through the first diode, and the second capacitor is connected to the first bus and the second bus through the second diode.

[0036] In this technical solution, when the first switch is in a closed state and the first capacitor and the second capacitor are in a charging state, the first capacitor and the second capacitor are connected to the DC bus in series with the third diode. That is, when the first switch is closed and the sum of the voltages of the first capacitor and the second capacitor is less than the bus voltage, the first capacitor, the third diode and the second capacitor are connected in series between the first bus and the second bus to charge the first capacitor and the second capacitor to ensure the stability of the bus voltage.

[0037] Furthermore, when the first switch is in a closed state and the first capacitor and the second capacitor are in a discharged state, the first capacitor is connected to the DC bus through the first diode, and the second capacitor is connected to the DC bus through the second diode. That is, when the first switch is closed and the bus voltage is lower than the voltage of the first capacitor or the bus voltage is lower than the voltage of the second capacitor, the first capacitor and the second capacitor are connected to the DC bus through the first diode and the second diode respectively, and discharged to the DC bus to ensure the stability of the bus voltage.

[0038] In this technical solution, the first capacitor and the second capacitor are connected to the DC bus in different ways under different circumstances, so that the lowest value of the bus voltage is always about half of the AC voltage amplitude. In this way, the torque pulsation during the operation of the motor to be controlled is reduced, the speed fluctuation of the motor to be controlled is reduced, and the noise during the operation of the motor to be controlled is reduced.

[0039] In the above technical solution, when the first switch is disconnected, the first capacitor and the second capacitor are not connected to the first bus and the second bus.

[0040] In this technical solution, when the speed of the motor to be controlled is high and the output power of the motor is large, the first switch will be in the disconnected state, so that the capacitor component is not connected to the DC bus, that is, the controller of the motor is in normal working mode, so that the motor to be controlled can provide greater output power.

[0041] Specifically, when the motor to be controlled has a high speed and a high output power, the motor to be controlled will not generate torque ripples that are integer multiples of the AC power supply voltage frequency. Therefore, when the motor to be controlled has a high speed and a high output power, the first switch needs to be in an off state, that is, there is no need to connect the capacitor component to the DC bus, so that the motor controller is in a normal operating mode, allowing the motor to provide a higher output power.

[0042] In this technical solution, when the speed of the motor to be controlled is high and the output power of the motor is large, the first switch is set to the disconnected state, so that the controller of the motor is in normal working mode, so that the motor to be controlled can provide higher output power, thereby improving the working efficiency of the motor to be controlled.

[0043] In the above technical solution, the above control circuit further includes a capacitor control circuit, which is in communication connection with the first switch and is used to control the first switch to be closed and opened.

[0044] In this technical solution, a capacitor control circuit is further provided in the control circuit. Specifically, the capacitor control circuit is in communication connection with the first switch and can control the first switch to be closed or opened according to the operating state of the motor to be controlled.

[0045] Specifically, when the speed of the motor to be controlled is low and the torque required is large, the capacitor control circuit controls the above-mentioned first switch to be closed. When the speed of the motor to be controlled is high and the output power of the motor is large, the capacitor control circuit controls the above-mentioned first switch to be opened.

[0046] In this technical solution, the capacitor control circuit can control the opening and closing of the first switch according to the operating state of the motor to be controlled, and then control whether to connect the first capacitor and the second capacitor to the DC bus, so that the bus voltage is always about half of the AC voltage amplitude. In this way, the torque pulsation during the operation of the motor to be controlled is reduced, the speed fluctuation of the motor to be controlled is reduced, and the noise during the operation of the motor to be controlled is reduced.

[0047] In the above technical solution, the above control circuit further includes a first resistor, which is connected in parallel with the first capacitor.

[0048] In this technical solution, the control circuit further includes a first resistor. Specifically, the first resistor and the first capacitor are connected in parallel. Specifically, when the first switch is closed and the first and second capacitors are in a charging state, the charging voltage of the first capacitor can be adjusted by adjusting the resistance of the first resistor, thereby precisely controlling the charging process of the first and second capacitors.

[0049] In this technical solution, the charging voltage of the first capacitor can be adjusted by the resistance value of the first resistor, thereby achieving precise control of the charging process of the first capacitor and the second capacitor.

[0050] In the above technical solution, the above control circuit further includes a second resistor, which is connected in parallel with the second capacitor.

[0051] In this technical solution, the control circuit further includes a second resistor. Specifically, the second resistor and the second capacitor are connected in parallel. Specifically, when the first switch is closed and the first and second capacitors are in a charging state, the charging voltage of the second capacitor can be adjusted by adjusting the resistance of the second resistor, thereby precisely controlling the charging process of the first and second capacitors.

[0052] In this technical solution, the charging voltage of the second capacitor can be adjusted by the resistance value of the second resistor, thereby achieving precise control of the charging process of the first capacitor and the second capacitor.

[0053] In the above technical solution, the above control circuit further includes a fourth diode, which is connected in parallel with the first switch.

[0054] In this technical solution, the control circuit is further provided with a fourth diode, and the fourth diode is in parallel with the first switch. Specifically, the anode of the fourth diode is connected to the second end of the first switch, and the cathode of the fourth diode is connected to the first end of the first switch.

[0055] Specifically, by connecting the fourth diode in parallel with the first switch, the current flowing through the first switch can be shared, the first switch can be prevented from being broken down, and the reliability of the operation of the motor controller is ensured.

[0056] In this technical solution, by providing a fourth diode and connecting the fourth diode in parallel with the first switch, the reliability of the operation of the first switch is ensured, thereby ensuring the reliability of the operation of the motor controller.

[0057] In the above technical solution, the above control circuit further includes: a third capacitor, a first end of the third capacitor is connected to the first bus, and a second end of the third capacitor is connected to the second bus.

[0058] In this technical solution, by setting a third capacitor and connecting the third capacitor between the first bus and the second bus, it is ensured that the motor can have a larger output power when the motor speed is high, and at the same time, the reliability of the motor controller is ensured.

[0059] In the above technical solution, the first switch is an electronic switch or a mechanical switch.

[0060] In this technical solution, the first switch may be an electronic tube, such as an IGBT transistor or a silicon carbide switch tube, or may be a mechanical switch.

[0061] In the above technical solution, the number of the first capacitor and / or the second capacitor is one or more.

[0062] In this technical solution, the number of the first capacitor and the second capacitor in the control circuit can be set to one or more. Specifically, setting the number of the first capacitor or the second capacitor to multiple can improve the voltage resistance and filtering effect of the capacitor component.

[0063] In the above technical solution, when there are multiple first capacitors and / or multiple second capacitors, the multiple first capacitors are connected in parallel or in series, and the multiple second capacitors are connected in parallel or in series.

[0064] In this technical solution, if multiple first capacitors are provided, the multiple first capacitors can be connected in series or in parallel. Specifically, connecting multiple first capacitors in series can improve the voltage resistance of the capacitor assembly and ensure the stability of the control circuit operation; while connecting multiple first capacitors in parallel can improve the filtering effect of the capacitor assembly and ensure the reliability of the control circuit operation.

[0065] Furthermore, if there are multiple second capacitors, the multiple second capacitors can be connected in series or in parallel. Specifically, connecting multiple second capacitors in series can improve the voltage resistance of the capacitor assembly and ensure the stability of the control circuit operation; while connecting multiple second capacitors in parallel can improve the filtering effect of the capacitor assembly and ensure the reliability of the control circuit operation.

[0066] In this technical solution, when there are multiple first capacitors or multiple second capacitors, the voltage resistance and filtering effect of the capacitor component are improved by connecting multiple first capacitors or multiple second capacitors in series or in parallel, thereby ensuring the stability and reliability of the motor operation when the operating state of the motor to be controlled is controlled by the motor controller.

[0067] According to a second aspect of the present invention, a motor is provided, comprising the motor controller according to the above technical solution of the present invention. Therefore, the motor controller has all the beneficial technical effects of the motor controller according to the above technical solution of the present invention, and no further details will be given here.

[0068] According to a third aspect of the present invention, a laundry processing device is provided, comprising a motor controller according to the above technical solution of the present invention, or a motor according to the above technical solution of the present invention. Thus, the device has all the beneficial technical effects of the motor controller according to the above technical solution of the present invention, or the motor according to the above technical solution of the present invention, and no further details will be given here.

[0069] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0070] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which:

[0071] Figure 1 One of the schematic diagrams of a controller of a motor according to an embodiment of the present invention is shown;

[0072] Figure 2 A second schematic diagram of a controller for a motor according to an embodiment of the present invention is shown;

[0073] Figure 3 A third schematic diagram showing a controller for a motor according to an embodiment of the present invention;

[0074] Figure 4 A fourth schematic diagram showing a controller for a motor according to an embodiment of the present invention;

[0075] Figure 5 A fifth schematic diagram showing a controller of a motor according to an embodiment of the present invention;

[0076] Figure 6 A sixth schematic diagram showing a controller for a motor according to an embodiment of the present invention;

[0077] Figure 7 FIG7 shows a seventh schematic diagram of a controller for a motor according to an embodiment of the present invention;

[0078] Figure 8 An eighth schematic diagram showing a controller of a motor according to an embodiment of the present invention;

[0079] Figure 9 A ninth schematic diagram showing a controller of a motor according to an embodiment of the present invention;

[0080] Figure 10 FIG10 shows a schematic diagram of a controller of a motor according to an embodiment of the present invention;

[0081] Figure 11 FIG11 shows a schematic diagram of a controller of a motor according to an embodiment of the present invention;

[0082] Figure 12 FIG12 shows a schematic diagram of a controller of a motor according to an embodiment of the present invention;

[0083] Figure 13 The figure shows a bus voltage waveform diagram when the motor to be controlled is running according to an embodiment of the present invention.

[0084] in, Figures 1 to 12 , the corresponding relationship between the electronic components and the labels is: K1 is the first switch, C1 is the first capacitor, C2 is the second capacitor, C3 is the third capacitor, D1 is the first diode, D2 is the second diode, D3 is the third diode, D4 ​​is the fourth diode, R1 is the first resistor, and R2 is the second resistor. DETAILED DESCRIPTION

[0085] In order to more clearly understand the above aspects, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features therein can be combined with each other in the absence of conflict.

[0086] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0087] The following combination Figures 1 to 13 The motor controller, the motor, and the clothes processing device proposed in the embodiments of the present invention are described in detail through specific embodiments and their application scenarios.

[0088] Example 1

[0089] Figures 1 to 13 A controller for a motor according to an embodiment of the present invention is shown, wherein the controller of the motor includes: a DC bus; a rectifier circuit for converting the AC voltage output by an AC power supply into a DC voltage to power the DC bus; a control circuit, the control circuit including a capacitor component and a first switch K1, and the capacitor component is connected to the DC bus by controlling the first switch K1 to limit the minimum voltage on the DC bus to within a preset range; and an inverter circuit for converting the DC voltage on the DC bus into an AC voltage to control the operating state of the motor connected to the inverter circuit.

[0090] In this embodiment, the controller of the above-mentioned motor specifically includes a DC bus, which is used to provide a DC voltage to the inverter, so that the inverter converts the DC voltage into an AC voltage to provide an AC voltage for the motor to be controlled by the motor controller.

[0091] Furthermore, the motor controller further includes a rectifier circuit. Specifically, the input end of the rectifier circuit is connected to the AC power supply, and the output end of the rectifier circuit is connected to the DC bus. Specifically, when controlling the operation of the controlled motor, the rectifier circuit can obtain AC voltage from the AC power supply, convert the AC voltage into DC voltage, and input it into the DC bus to power the DC bus.

[0092] Furthermore, the controller of the motor further includes a control circuit, specifically, a first switch K1 and a capacitor assembly. Specifically, when the motor to be controlled has a low speed and a high torque demand, the first switch K1 is closed, connecting the capacitor assembly to the DC bus. The capacitor assembly adjusts the power factor on the DC bus by charging or discharging, ensuring that the minimum voltage between the DC buses remains within a preset range.

[0093] It should be noted that the above preset range is generally set to about half of the AC voltage amplitude.

[0094] It can be understood that when the speed of the motor to be controlled is low and the torque demand is large, the motor to be controlled is prone to generate torque pulsation that is an integer multiple of the AC power supply voltage frequency, resulting in the inability to stably control the motor speed. Therefore, when the speed of the motor to be controlled is low and the torque demand is large, the first switch K1 needs to be adjusted to a closed state to always control the minimum voltage between the DC bus bars within a preset range, thereby ensuring stable power supply to the motor to avoid torque pulsation when the motor to be controlled is running.

[0095] Specifically, when the speed of the motor to be controlled is high and the output power of the motor is large, the first switch K1 will be in the disconnected state, so that the capacitor component is not connected to the DC bus, and the motor controller is in normal working mode, so that the motor to be controlled can provide greater output power.

[0096] It is understood that when the motor to be controlled has a high speed and a high output power, the motor to be controlled will not generate torque ripples that are integer multiples of the AC power supply voltage frequency. Therefore, when the motor to be controlled has a high speed and a high output power, there is no need to adjust the first switch K1 to the closed state, that is, there is no need to connect the capacitor assembly to the DC bus, so that the motor controller is in normal operating mode, allowing the motor to provide a higher output power.

[0097] Furthermore, the motor controller includes an inverter circuit. Specifically, the inverter circuit has an input connected to a DC bus, and an output connected to the motor to be controlled. Specifically, when the motor controller controls the motor, the inverter circuit obtains a power-factor-adjusted DC voltage from the DC bus via the capacitor assembly, and converts the obtained DC voltage into an AC voltage to control the operation of the motor to be controlled.

[0098] For example, when the motor to be controlled is a two-phase motor, the connection relationship between the motor to be controlled and the inverter circuit is as follows: Figure 11 shown.

[0099] For example, when the motor to be controlled is a three-phase motor, the connection relationship between the motor to be controlled and the inverter circuit is as follows: Figure 12 shown.

[0100] In this embodiment, a first switch K1 and a capacitor component are provided in the control circuit of the motor controller. When the first switch K1 is closed, the capacitor component can be connected to the DC bus, and the minimum value of the bus voltage of the DC bus can always be controlled to be about half of the AC voltage amplitude, thereby avoiding the situation where torque pulsation easily occurs and the speed control is unstable when the motor to be controlled has a low speed and a large torque requirement, thereby ensuring the stability and reliability of the motor operation when the motor controller controls the operating state of the motor to be controlled, and at the same time effectively reducing the noise of the motor to be controlled during operation.

[0101] In the above embodiment, the DC bus specifically includes a first bus and a second bus, and the capacitor assembly specifically includes a first capacitor C1 and a second capacitor C2, wherein the first end of the first capacitor C1 is connected to the first bus, and the second end of the second capacitor C2 is connected to the second bus via a first switch K1; the control circuit further includes: a first diode D1, wherein the anode of the first diode D1 is connected to the second bus, and the cathode of the first diode D1 is connected to the second end of the first capacitor C1; a second diode D2, wherein the cathode of the second diode D2 is connected to the first bus, and the anode of the second diode D2 is connected to the first end of the second capacitor C2; and a third diode D3, wherein the anode of the third diode D3 is connected to the second end of the first capacitor C1, and the cathode of the third diode D3 is connected to the first end of the second capacitor C2.

[0102] In this embodiment, the DC bus specifically includes a first bus and a second bus, wherein the first bus is used to indicate a P bus and the second bus is used to indicate an N bus; the capacitor component specifically includes a first capacitor C1 and a second capacitor C2.

[0103] Specifically, when the first switch K1 is in a closed state and the first capacitor C1 and the second capacitor C2 are in a charging state, the first capacitor C1 and the second capacitor C2 can be connected to the above-mentioned DC bus in series; when the first switch K1 is in a closed state and the first capacitor C1 and the second capacitor C2 are in a discharging state, the first capacitor C1 and the second capacitor C2 can be connected to the above-mentioned DC bus in parallel.

[0104] Specifically, a first end of the first capacitor C1 is connected to the P bus (ie, the first bus), and a second end of the second capacitor C2 is connected to the N bus (ie, the second bus).

[0105] Furthermore, the above-mentioned control circuit is also provided with a first diode. Specifically, the anode of the first diode is connected to the above-mentioned second bus, and the cathode of the first diode D1 is connected to the second end of the above-mentioned first capacitor C1, that is, the first capacitor C1 and the first diode D1 are connected in series between the above-mentioned first bus and the above-mentioned second bus.

[0106] Specifically, when the motor to be controlled is operating normally, the voltage of the first bus is higher than the voltage of the second bus. By setting a diode in the opposite direction between the first bus and the second bus, the first capacitor C1 can be prevented from being directly connected to the above-mentioned DC bus, thereby ensuring that when the motor to be controlled is operating at high speed and high output power, the motor controller is in an operating mode without electrolytic capacitors (i.e., the above-mentioned normal operating mode). In addition, when the first switch K1 is closed, the voltage resonance generated by the first capacitor C1 during discharge can be effectively eliminated by the first diode D1, thereby ensuring the stability of the operation of the motor to be controlled.

[0107] Furthermore, the control circuit is further provided with a second diode D2. Specifically, the anode of the second diode D2 is connected to the first end of the second capacitor C2, and the cathode of the second diode D2 is connected to the first busbar, that is, the second capacitor C2 and the second diode D2 are connected in series between the first busbar and the second busbar.

[0108] Specifically, the voltage of the first bus is higher than the voltage of the second bus. By setting a diode in reverse between the first bus and the second bus, when the first switch K1 is closed, the voltage resonance generated by the second capacitor C2 during discharge can be effectively eliminated, thereby ensuring the stability of the operation of the motor to be controlled.

[0109] Furthermore, the control circuit is further provided with a third diode D3. Specifically, the anode of the third diode D3 is connected to the second end of the first capacitor C1, and the cathode of the third diode D3 is connected to the first end of the second capacitor C2. That is, the first capacitor C1 and the second capacitor C2 are connected in series between the first bus and the second bus via the third diode D3 and the first switch K1.

[0110] For example, when the motor controller proposed in this embodiment is used to control the motor to be controlled, the waveform of the bus voltage is as follows: Figure 13 As shown, through Figure 13 It can be seen that the controller of the motor proposed in this embodiment can control the minimum value of the bus voltage to about half of the AC voltage amplitude.

[0111] In this embodiment, when the first switch K1 is in a closed state and the sum of the voltages of the first capacitor C1 and the second capacitor C2 is lower than the bus voltage, the first capacitor C1 and the second capacitor C2 can be connected in series between the first bus and the second bus through the third diode D3, so that the first capacitor C1 and the second capacitor C2 are in a charged state.

[0112] Specifically, when the first switch K1 is closed and the bus voltage is lower than the voltage of the first capacitor C1, or when the bus voltage is lower than the voltage of the second capacitor C2, the first capacitor C1 and the second capacitor C2 are connected to the DC bus via the first diode D1 and the second diode D2, respectively. The first capacitor C1 and the second capacitor C2 are connected in parallel, and discharge is made to the DC bus via the first capacitor C1 and the second capacitor C2. Through the above-mentioned embodiments, the present invention can control the minimum value of the bus voltage to approximately half the amplitude of the AC voltage, thereby reducing torque ripple during operation of the controlled motor, reducing speed fluctuation of the controlled motor, and reducing noise during operation of the controlled motor.

[0113] In the above embodiment, the first end of the first switch K1 is connected to the second end of the second capacitor C2, and the second end of the first switch K1 is connected to the second busbar.

[0114] like Figure 1 As shown, in this embodiment, the first end of the first switch K1 is connected to the second end of the second capacitor C2, and the second end of the first switch K1 is connected to the second bus, that is, the first switch K1 is connected between the second capacitor C2 and the second bus.

[0115] like Figure 2 As shown, in some embodiments, the first end of the first switch K1 can be connected to the anode of the second diode D2, and the second end of the first switch K1 can be connected to the first end of the second capacitor C2, that is, the first switch K1 can be connected in series between the second diode and the second capacitor C2.

[0116] like Figure 3 As shown, in some embodiments, the first end of the first switch K1 can be connected to the cathode of the third diode D3, and the second end of the first switch K1 can be connected to the first end of the second capacitor C2, that is, the first switch K1 can be connected in series between the third diode and the second capacitor C2.

[0117] like Figure 4 As shown, in some embodiments, the first end of the first switch K1 can be connected to the second end of the first capacitor C1, and the second end of the first switch K1 can be connected to the anode of the third diode D3, that is, the first switch K1 can be connected in series between the first capacitor C1 and the third diode D3.

[0118] like Figure 5 As shown, in some embodiments, the first end of the first switch K1 can be connected to the second end of the first capacitor C1, and the second end of the first switch K1 can be connected to the cathode of the first diode D1, that is, the first switch K1 can be connected in series between the first capacitor C1 and the first diode.

[0119] like Figure 6 As shown, in some embodiments, the first end of the first switch K1 can be connected to the first bus, and the second end of the first switch K1 can be connected to the first end of the first capacitor C1, that is, the first switch K1 can be connected in series between the first bus and the first capacitor C1.

[0120] like Figure 7 As shown, in some embodiments, the first end of the first switch K1 can be connected to the cathode of the first diode D1 and the second end of the second capacitor C2, and the second end of the first switch K1 can be connected to the second bus, that is, the first switch K1 can be connected in series between the common end of the second capacitor C2 and the first diode D1 and the second bus.

[0121] like Figure 8 As shown, in some embodiments, the first end of the first switch K1 can be connected to the first bus, and the second end of the first switch K1 can be connected to the first end of the first capacitor C1 and the cathode of the second diode D2, that is, the first switch K1 can be connected in series between the common end of the first capacitor C1 and the second diode D2 and the first bus.

[0122] In this embodiment, by connecting the first switch K1 between the second capacitor C2 and the second bus, the embodiment of the present invention can connect the above-mentioned first capacitor C1 and the above-mentioned second capacitor C2 to the DC bus when the first switch K1 is closed, so as to control the minimum value of the bus voltage to about half of the AC voltage amplitude.

[0123] In the above embodiment, when the first switch K1 is closed and the first capacitor C1 and the second capacitor C2 are in a charging state, the first capacitor C1 and the second capacitor C2 are connected in series to the first bus and the second bus through the third diode D3; or when the first switch K1 is closed and the first capacitor C1 and the second capacitor C2 are in a discharging state, the first capacitor C1 is connected to the first bus and the second bus through the first diode D1, and the second capacitor C2 is connected to the first bus and the second bus through the second diode D2.

[0124] In this embodiment, when the first switch K1 is in a closed state, if the first capacitor C1 and the second capacitor C2 are in a charged state, the first capacitor C1 and the second capacitor C2 are connected to the DC bus in series with the third diode D3.

[0125] Specifically, when the first switch K1 is in a closed state and the sum of the voltages of the first capacitor C1 and the second capacitor C2 is less than the bus voltage, the first capacitor C1, the third diode D3, and the second capacitor C2 are connected in series between the first bus and the second bus, so that the first capacitor C1 and the second capacitor C2 can be charged, thereby ensuring the stability of the bus voltage.

[0126] Furthermore, when the first switch K1 is in a closed state and the first capacitor C1 and the second capacitor C2 are in a discharged state, the first capacitor C1 is connected to the DC bus in series with the first diode D1, and the second capacitor C2 is connected to the DC bus in series with the second diode D2. That is, when the first switch K1 is in a closed state and the bus voltage is lower than the voltage of the first capacitor C1, or the bus voltage is lower than the voltage of the second capacitor C2, the first capacitor C1 and the second capacitor C2 are connected to the DC bus through the first diode D1 and the second diode D2, respectively, to discharge into the DC bus to ensure the stability of the bus voltage.

[0127] In this embodiment, by connecting the first capacitor C1 and the second capacitor C2 to the DC bus in different ways under different circumstances, the lowest value of the bus voltage is always about half of the AC voltage amplitude. In this way, the torque pulsation during the operation of the motor to be controlled is reduced, the speed fluctuation of the motor to be controlled is reduced, and the noise during the operation of the motor to be controlled is reduced.

[0128] In the above embodiment, when the first switch K1 is disconnected, the first capacitor C1 and the second capacitor C2 are not connected to the first busbar and the second busbar.

[0129] In this embodiment, when the speed of the motor to be controlled is high and the output power of the motor is large, the first switch K1 will be in the disconnected state, so that the capacitor component is not connected to the DC bus, that is, the controller of the motor is in normal working mode, so that the motor to be controlled can provide greater output power.

[0130] Specifically, when the motor to be controlled has a high speed and a high output power, the motor to be controlled will not generate torque ripples that are integer multiples of the AC power supply voltage frequency. Therefore, when the motor to be controlled has a high speed and a high output power, the first switch K1 needs to be in the off state, that is, the capacitor component does not need to be connected to the DC bus, so that the motor controller is in normal operating mode, allowing the motor to provide a higher output power.

[0131] In this embodiment, when the speed of the motor to be controlled is high and the output power of the motor is large, the first switch K1 is set to the disconnected state, so that the controller of the motor is in normal working mode, so that the motor to be controlled can provide higher output power, thereby improving the working efficiency of the motor to be controlled.

[0132] In the above embodiment, the control circuit further includes a capacitor control circuit, which is in communication with the first switch K1 and is used to control the first switch K1 to be closed or opened.

[0133] In this embodiment, a capacitor control circuit is further provided in the control circuit. Specifically, the capacitor control circuit is in communication connection with the first switch K1 and can control the first switch K1 to be closed or opened according to the operating state of the motor to be controlled.

[0134] Specifically, when the speed of the motor to be controlled is low and the torque required is large, the capacitor control circuit controls the above-mentioned first switch K1 to be closed. When the speed of the motor to be controlled is high and the output power of the motor is large, the capacitor control circuit controls the above-mentioned first switch K1 to be opened.

[0135] In this embodiment, the capacitor control circuit can control the opening and closing of the first switch K1 according to the operating state of the motor to be controlled, and then control whether to connect the first capacitor C1 and the second capacitor C2 to the DC bus, so that the bus voltage is always about half of the AC voltage amplitude. In this way, the torque pulsation during the operation of the motor to be controlled is reduced, the speed fluctuation of the motor to be controlled is reduced, and the noise during the operation of the motor to be controlled is reduced.

[0136] In the above embodiment, the control circuit further includes a first resistor R1 , and the first resistor R1 is connected in parallel with the first capacitor C1 .

[0137] In this embodiment, the control circuit further includes a first resistor R1. Specifically, the first resistor R1 and the first capacitor C1 are connected in parallel. Specifically, when the first switch K1 is closed and the first capacitor C1 and the second capacitor C2 are in a charging state, the charging voltage of the first capacitor C1 can be adjusted by adjusting the resistance of the first resistor R1 to precisely control the charging process of the first capacitor C1 and the second capacitor C2.

[0138] In this embodiment, the charging voltage of the first capacitor C1 can be adjusted by the resistance value of the first resistor R1 , thereby achieving precise control over the charging process of the first capacitor C1 and the second capacitor C2 .

[0139] In the above embodiment, the control circuit further includes a second resistor R2 , and the second resistor R2 is connected in parallel with the second capacitor C2 .

[0140] In this embodiment, the control circuit further includes a second resistor R2. Specifically, the second resistor R2 and the second capacitor C2 are connected in parallel. Specifically, when the first switch K1 is closed and the first capacitor C1 and the second capacitor C2 are in a charging state, the charging voltage of the second capacitor C2 can be adjusted by adjusting the resistance value of the second resistor R2 to precisely control the charging process of the first capacitor C1 and the second capacitor C2.

[0141] In this embodiment, the charging voltage of the second capacitor C2 can be adjusted by adjusting the resistance of the second resistor R2, thereby achieving precise control over the charging process of the first capacitor C1 and the second capacitor C2.

[0142] In the above embodiment, the control circuit further includes a fourth diode D4 , which is connected in parallel with the first switch K1 .

[0143] In this embodiment, the control circuit is further provided with a fourth diode D4, and the fourth diode D4 is connected in parallel with the first switch K1. Specifically, the anode of the fourth diode is connected to the second end of the first switch K1, and the cathode of the fourth diode is connected to the first end of the first switch K1.

[0144] Specifically, by connecting the fourth diode D4 and the first switch K1 in parallel, the current flowing through the first switch K1 can be shared, and the first switch K1 can be prevented from being broken down, thereby ensuring the reliability of the motor controller.

[0145] In this embodiment, by providing the fourth diode D4 and setting the fourth diode D4 and the first switch K1 to be connected in parallel, the reliability of the first switch K1 is ensured, thereby ensuring the reliability of the motor controller.

[0146] In the above technical solution, the above control circuit further includes: a third capacitor C3, a first end of the third capacitor C3 is connected to the first bus, and a second end of the third capacitor is connected to the second bus.

[0147] In this technical solution, by setting a third capacitor C3 and connecting the third capacitor C3 between the first bus and the second bus, it is ensured that the motor can have a larger output power when the speed is high, and at the same time ensure the reliability of the motor controller.

[0148] In the above embodiment, the first switch K1 is an electronic switch or a mechanical switch.

[0149] In this technical solution, the first switch K1 may be an electronic tube, such as an IGBT transistor or a silicon carbide switch tube. The first switch K1 may also be a mechanical switch.

[0150] In the above embodiment, the number of the first capacitor C1 and / or the second capacitor C2 is one or more.

[0151] In this embodiment, the number of the first capacitor C1 and the second capacitor C2 in the control circuit can be one or more. Specifically, setting the number of the first capacitor C1 or the second capacitor C2 to multiple can improve the voltage resistance and filtering effect of the capacitor component.

[0152] In the above embodiment, when there are multiple first capacitors C1 and / or multiple second capacitors C2, the multiple first capacitors C1 are connected in parallel or in series, and the multiple second capacitors C2 are connected in parallel or in series.

[0153] In this embodiment, if there are multiple first capacitors C1, the multiple first capacitors C1 can be connected in series or in parallel. Specifically, connecting multiple first capacitors C1 in series can improve the voltage resistance of the capacitor assembly and ensure the stability of the control circuit operation; while connecting multiple first capacitors C1 in parallel can improve the filtering effect of the capacitor assembly and ensure the reliability of the control circuit operation.

[0154] Furthermore, if the second capacitor C2 is provided in plurality, the plurality of second capacitors C2 may be connected in series or in parallel. Specifically, connecting the plurality of second capacitors C2 in series can improve the voltage resistance of the capacitor assembly and ensure the stability of the control circuit operation; while connecting the plurality of second capacitors C2 in parallel can improve the filtering effect of the capacitor assembly and ensure the reliability of the control circuit operation.

[0155] For example, Figure 9It is a circuit diagram of a motor controller in which a plurality of first capacitors C1 are connected in parallel and a plurality of second capacitors C2 are connected in parallel.

[0156] For example, Figure 10 The circuit diagram of the controller of the motor is shown as follows: a plurality of first capacitors C1 are connected in series, and a plurality of second capacitors C2 are connected in series. Figure 10 It can be seen that when multiple first capacitors C1 are connected in series, the number of any one first resistor R1 is also multiple, corresponding to the number of first capacitors C1, and connected in parallel on both sides of the first capacitor C1.

[0157] In this embodiment, when there are multiple first capacitors C1 or multiple second capacitors C2, by connecting multiple first capacitors C1 or multiple second capacitors C2 in series or in parallel, the voltage resistance and filtering effect of the capacitor component are improved, thereby ensuring the stability and reliability of the motor operation when the operating state of the motor to be controlled is controlled by the motor controller.

[0158] Example 2:

[0159] According to a second embodiment of the present invention, a motor is provided, including the motor controller provided in the above embodiment of the present invention. Therefore, all the beneficial technical effects of the motor controller provided in the above embodiment of the present invention are achieved, and no further details will be given here.

[0160] Example 3:

[0161] According to a third embodiment of the present invention, a laundry processing device is provided, comprising the motor controller or the motor provided in the above-mentioned embodiments of the present invention. Thus, the device has all the beneficial technical effects of the motor controller or the motor provided in the above-mentioned embodiments of the present invention, and no further details will be given here.

[0162] In the description of the present invention, the term "plurality" refers to two or more than two. Unless otherwise expressly defined, the orientations or positional relationships indicated by the terms "upper" and "lower" are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention. The terms "connect," "install," and "fix" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0163] In the description of the present invention, the terms "one embodiment," "some embodiments," "specific embodiments," etc., mean that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in multiple embodiments or examples of the present invention. In the present invention, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0164] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A motor controller, characterized in that: include: DC bus; The rectifier circuit is used to convert the AC voltage output by the AC power supply into a DC voltage to supply power to the DC bus; A control circuit, comprising a capacitor assembly and a first switch, configured to connect the capacitor assembly to the DC bus by controlling the first switch to limit a minimum voltage on the DC bus to within a preset range; An inverter circuit is used to convert the DC voltage on the DC bus into an AC voltage to control the working state of the motor connected to the inverter circuit; The DC bus includes a first bus and a second bus, the capacitor assembly includes a first capacitor and a second capacitor, a first end of the first capacitor is connected to the first bus, and a second end of the second capacitor is connected to the second bus via a first switch; The control circuit also includes: a first diode, wherein the anode of the first diode is connected to the second busbar, and the cathode of the first diode is connected to the second end of the first capacitor; a second diode, wherein a cathode of the second diode is connected to the first bus bar, and an anode of the second diode is connected to the first end of the second capacitor; A third diode, wherein an anode of the third diode is connected to the second end of the first capacitor, and a cathode of the third diode is connected to the first end of the first capacitor.

2. The controller of the motor according to claim 1, characterized in that The first end of the first switch is connected to the second end of the second capacitor, and the second end of the first switch is connected to the second bus.

3. The controller of the motor according to claim 2, characterized in that When the first switch is closed and the first capacitor and the second capacitor are in a charging state, the first capacitor and the second capacitor are connected in series to the first bus and the second bus through the third diode; or When the first switch is closed and the first capacitor and the second capacitor are in a discharging state, the first capacitor is connected to the first bus and the second bus through the first diode, and the second capacitor is connected to the first bus and the second bus through the second diode.

4. The controller of the motor according to claim 2, characterized in that When the first switch is disconnected, the first capacitor and the second capacitor are not connected to the first busbar and the second busbar.

5. The controller of the motor according to any one of claims 1 to 4, characterized in that: The control circuit also includes: The capacitor control circuit is in communication with the first switch and is used to control the first switch to be closed and opened.

6. The controller of the motor according to any one of claims 1 to 4, characterized in that: The control circuit also includes: A first resistor is connected in parallel with the first capacitor.

7. The controller of the motor according to any one of claims 1 to 4, characterized in that: The control circuit also includes: A second resistor is connected in parallel with the second capacitor.

8. The controller of the motor according to any one of claims 1 to 4, characterized in that: The control circuit also includes: A fourth diode is connected in parallel with the first switch.

9. The controller of the motor according to any one of claims 1 to 4, characterized in that: The control circuit also includes: A third capacitor, wherein a first end of the third capacitor is connected to the first bus bar, and a second end of the third capacitor is connected to the second bus bar.

10. The controller of the motor according to any one of claims 1 to 4, characterized in that: The first switch is an electronic switch or a mechanical switch.

11. The controller of the motor according to any one of claims 1 to 4, characterized in that: The number of the first capacitor and / or the second capacitor is one or more.

12. The controller of the motor according to claim 11, characterized in that In the case where there are multiple first capacitors and / or multiple second capacitors, the multiple first capacitors are connected in parallel or in series, and the multiple second capacitors are connected in parallel or in series.

13. A motor, characterized in that: include: A controller for an electric motor as claimed in any one of claims 1 to 12.

14. A clothes processing device, characterized in that: include: A controller for a motor according to any one of claims 1 to 12; or The motor of claim 13.

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