Motor energy recovery circuit and electrical device

Abstract

The application relates to a motor energy recovery circuit and a power utilization device. The motor energy recovery circuit comprises a control circuit, a rectifier circuit, an energy storage circuit and a charging switch circuit. The rectifier circuit is used for connecting a motor to rectify an induced electromotive force generated by the motor in a stop running condition; the energy storage circuit is connected with the rectifier circuit and is used for storing the rectified electric energy output by the rectifier circuit; and the charging switch circuit is connected with the energy storage circuit, an energy storage device and the control circuit. The control circuit controls the charging switch circuit to be turned on so as to transmit the electric energy stored in the energy storage circuit to the energy storage device. Thus, when the motor stops running, the induced electromotive force generated by the rotor of the motor due to inertia in the stop stage cutting a magnetic induction line can be stored in the energy storage device by the motor energy recovery circuit. When electric energy is needed, the energy storage device can supply power by using the electric energy, so that the energy is used efficiently, and the energy utilization rate is improved.

Description

Technical Field

[0001] This application relates to the field of motor technology, and in particular to a motor energy recovery circuit and electrical equipment. Background Technology

[0002] With the development of science and technology, electric motors, as power devices, have been widely used in many fields such as industry, transportation, home appliances, medical care, and aerospace, becoming one of the key driving forces for the development of modern science and technology.

[0003] During the process of a motor stopping, the rotor will continue to rotate for a period of time due to inertia. As a motor is an inductive load, the rotor generates an induced electromotive force (EMF) by cutting magnetic field lines during the stopping phase. Currently, to prevent this induced EMF from becoming too high and damaging components in the circuit, diodes are commonly used in the industry to construct the freewheeling circuit. This freewheeling circuit generates an induced current, which is released as heat within the motor's windings.

[0004] Clearly, this method of simply releasing induced electromotive force in the form of heat energy cannot achieve efficient energy utilization and results in a significant energy waste. Utility Model Content

[0005] Therefore, it is necessary to provide a motor energy recovery circuit and electrical equipment to address the problem of ineffective utilization of motor energy.

[0006] An energy recovery circuit for an electric motor includes:

[0007] Control circuit;

[0008] A rectifier circuit is used to connect to the motor and rectify the induced electromotive force generated by the motor when it is stopped.

[0009] An energy buffer circuit is connected to the rectifier circuit, and the energy buffer circuit is used to store the rectified electrical energy output by the rectifier circuit;

[0010] A charging switch circuit is connected to the energy buffer circuit, the energy storage device, and the control circuit; the control circuit controls the charging switch circuit to turn on so as to transfer the electrical energy stored in the energy buffer circuit to the energy storage device.

[0011] In one embodiment, the energy caching circuit includes:

[0012] A storage inductor, wherein a first end of the storage inductor is connected to the rectifier circuit, and a second end of the storage inductor is connected to the charging switch circuit;

[0013] A storage switch unit is provided, which is connected to the second terminal of the storage inductor and the control circuit. The control circuit is also connected to the motor and controls the storage switch unit to turn on according to the motor's stop operation condition.

[0014] In one embodiment, the storage switching unit includes a first MOS transistor; the first terminal of the first MOS transistor is connected to the second terminal of the storage inductor, the second terminal of the first MOS transistor is grounded, and the gate of the first MOS transistor is connected to the control circuit.

[0015] In one embodiment, the charging switch circuit includes a charging switch unit and a switch driving unit; the switch driving unit is connected to the control circuit and the charging switch unit, and the charging switch unit is connected to the energy buffer circuit and the energy storage device; the control circuit is used to control the charging switch unit through the switch driving unit.

[0016] In one embodiment, the charging switch unit includes a second MOSFET and a first resistor; the first terminal of the second MOSFET is connected to the energy cache circuit, the second terminal of the second MOSFET is connected to the energy storage device, and the gate of the second MOSFET is connected to the control circuit; the first terminal of the first resistor is connected to the first terminal of the second MOSFET, and the second terminal of the first resistor is connected to the gate of the second MOSFET.

[0017] In one embodiment, the switch driving unit includes a transistor, a second resistor, and a third resistor; the first end of the second resistor is connected to the control circuit, the second end of the second resistor is connected to the base of the transistor and the first end of the third resistor, the emitter of the transistor and the second end of the third resistor are grounded, and the collector of the transistor is connected to the gate of the second MOS transistor.

[0018] In one embodiment, the motor energy recovery circuit further includes a freewheeling circuit; the first end of the freewheeling circuit is connected to the energy buffer circuit, and the second end of the freewheeling circuit is connected to the charging switch unit.

[0019] In one embodiment, the freewheeling circuit includes a third MOSFET; the first terminal of the third MOSFET is connected to the charging switch unit, the second terminal of the third MOSFET is connected to the energy cache circuit, and the gate of the third MOSFET is connected to the common terminal of the charging switch unit and the switch driving unit.

[0020] In one embodiment, the rectifier circuit includes a rectifier diode; the anode of the rectifier diode is connected to the motor, and the cathode of the rectifier diode is connected to the energy buffer circuit.

[0021] In one embodiment, the control circuit includes a sampling unit and a controller; the sampling unit is connected to the energy cache circuit and the controller, and the controller is used to control the charging switch circuit according to the stored power of the energy cache circuit obtained by the sampling unit.

[0022] An electrical device includes: a motor, an energy storage device, and a motor energy recovery circuit as described above.

[0023] The aforementioned motor energy recovery circuit and electrical equipment include a control circuit, a rectifier circuit, an energy buffer circuit, and a charging switch circuit. The rectifier circuit is connected to the motor to rectify the induced electromotive force generated when the motor is stopped. The energy buffer circuit is connected to the rectifier circuit to store the rectified electrical energy output from the rectifier circuit. The charging switch circuit connects the energy buffer circuit, the energy storage device, and the control circuit. The control circuit controls the charging switch circuit to conduct, transferring the electrical energy stored in the energy buffer circuit to the energy storage device. Thus, when the motor is stopped, the motor energy recovery circuit stores the induced electromotive force generated by the rotor cutting magnetic lines of force due to inertia during the stop phase into the energy storage device. When electrical energy is needed, the energy storage device can use this electrical energy to supply power, thereby achieving efficient energy utilization and improving energy efficiency. Simultaneously, compared to the traditional method of releasing induced electromotive force as heat, it reduces the heat dissipation requirements of the electrical equipment during motor braking. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of a motor energy recovery circuit according to one embodiment;

[0026] Figure 2 A schematic diagram of a motor energy recovery circuit according to another embodiment;

[0027] Figure 3 This is a schematic diagram of a motor energy recovery circuit according to yet another embodiment;

[0028] Figure 4 This is a schematic diagram of a motor energy recovery circuit according to yet another embodiment;

[0029] Figure 5 This is a schematic diagram of the circuit structure of a motor energy recovery circuit according to one embodiment. Detailed Implementation

[0030] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0032] It is understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0033] It is understood that the term "connection" in the following embodiments should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have electrical signal or data transmission with each other.

[0034] It is understandable that "at least one" refers to one or more, and "multiple" refers to two or more. "At least a part of an element" refers to part or all of an element.

[0035] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising / including” or “having,” etc., specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.

[0036] In one exemplary embodiment, a motor energy recovery circuit is provided. This motor energy recovery circuit can be incorporated into an electronic device that includes a motor, and the electronic device may include, but is not limited to, a fan, a range hood, a dishwasher, etc. Figure 1As shown, the motor energy recovery circuit 100 can recover the induced electromotive force generated by the rotor cutting magnetic field lines due to inertia during the stop phase of the motor 200 when it stops running, and send it to the energy storage device 300. The energy storage device 300 can be a battery or a gold capacitor or other device that can store electrical energy.

[0037] The motor energy recovery circuit 100 includes a control circuit 110, a rectifier circuit 120, an energy buffer circuit 130, and a charging switch circuit 140. The rectifier circuit 120 is connected to the motor 200 to rectify the induced electromotive force generated by the motor 200 when it is not running. The energy buffer circuit 130 is connected to the rectifier circuit 120 and stores the rectified electrical energy output from the rectifier circuit 120. The charging switch circuit 140 is connected to the energy buffer circuit 130, the energy storage device 300, and the control circuit 110. The control circuit 110 controls the charging switch circuit 140 to conduct, transferring the electrical energy stored in the energy buffer circuit 130 to the energy storage device 300.

[0038] Motor 200 can be a DC motor or an AC motor. After motor 200 stops running, its rotor continues to rotate due to inertia, cutting magnetic field lines to generate an induced electromotive force, which is usually an AC voltage. Rectifier circuit 120 is connected to motor 200 and can rectify this AC voltage into a DC voltage, forming a DC voltage that can be used for energy storage.

[0039] The DC power rectified by the rectifier circuit 120 is first stored in the energy buffer circuit 130. When the control circuit 110 controls the charging switch circuit 140 to turn on, the energy buffer circuit 130 begins to discharge, transferring the stored power through the charging switch circuit 140 and storing it in the energy storage device 300. Thus, the energy buffer circuit 130 enables rapid charging and discharging of power, effectively buffering the impact of fluctuations in the regenerated energy (i.e., induced electromotive force) of the motor 200 on the energy storage device 300 during direct charging.

[0040] The control circuit 110 can also control the charging switch circuit 140 to disconnect, thereby stopping the transmission of electrical energy to the energy storage device 300. This allows charging to stop when the energy storage device 300 is fully charged or when overvoltage occurs, ensuring charging safety and preventing energy backflow that could cause losses.

[0041] The aforementioned motor energy recovery circuit includes a control circuit 110, a rectifier circuit 120, an energy buffer circuit 130, and a charging switch circuit 140. The rectifier circuit 120 is connected to the motor 200 to rectify the induced electromotive force generated by the motor 200 when it is stopped. The energy buffer circuit 130 is connected to the rectifier circuit 120 to store the rectified electrical energy output from the rectifier circuit 120. The charging switch circuit 140 is connected to the energy buffer circuit 130, the energy storage device 300, and the control circuit 110. The control circuit 110 controls the charging switch circuit 140 to conduct, transferring the electrical energy stored in the energy buffer circuit 130 to the energy storage device 300. Thus, when the motor 200 is stopped, the motor energy recovery circuit 100 stores the induced electromotive force generated by the rotor cutting magnetic lines of force due to inertia during the stop phase in the energy storage device 300, so that the energy storage device 300 can use this electrical energy to power devices or circuits that require power when needed. This enables efficient use of energy, improves energy utilization, and reduces the heat dissipation requirements of electrical equipment when the motor brakes (in traditional technology, the induced electromotive force is released in the form of heat energy).

[0042] In some embodiments, the control circuit 110 is also connected to the energy cache circuit 130, and is capable of sampling the stored energy of the energy cache circuit 130 and controlling the charging switch circuit 140 to turn on based on the stored energy of the energy cache circuit 130. As an example, the control circuit 110 controls the charging switch circuit 140 to turn on when the stored energy of the energy cache circuit 130 is greater than or equal to a preset voltage threshold. The preset voltage threshold can be set according to actual conditions, such as based on the performance parameters of the energy storage device 300.

[0043] Therefore, the energy buffer circuit 130 can be used to achieve voltage boosting and efficient energy transfer, so that the charging voltage of the energy storage device 300 is better matched with the demand, and the risk of damaging the energy storage device 300 during the recycling process is reduced.

[0044] In some embodiments, such as Figure 2 As shown, the control circuit 110 includes a sampling unit 111 and a controller 112. The sampling unit 111 is connected to the energy cache circuit 130 and the controller 112. The controller 112 is used to control the charging switch circuit 140 according to the stored power of the energy cache circuit 130 sampled by the sampling unit 111.

[0045] The controller 112 can be an existing control chip in the electronic device, such as a control chip used to control a motor, or it can be a separately set control chip.

[0046] The circuit structure of sampling unit 111 is not limited. As an example, sampling unit 111 can adopt a resistor sampling circuit, for example, including a first sampling resistor and a second sampling resistor connected in series. The first end of the first sampling resistor is connected to the common terminal of the energy cache circuit 130 and the charging switch circuit 140. The second end of the first sampling resistor is grounded through the second sampling resistor. The second end of the first sampling resistor is also connected to the controller 112.

[0047] In this embodiment, by setting up a sampling unit 111 and a controller 112, the stored power of the energy cache circuit 130 can be detected, and when the stored power reaches the expected value (preset voltage threshold), the charging switch circuit 140 can be turned on in time to efficiently transfer the cached power to the energy storage device 300, thereby achieving efficient energy recovery.

[0048] In some embodiments, such as Figure 3 As shown, the energy buffer circuit 130 includes a storage inductor L1 and a storage switch unit 131. The first terminal of the storage inductor L1 is connected to the rectifier circuit 120, and the second terminal of the storage inductor L1 is connected to the charging switch circuit 140. The storage switch unit 131 is connected to the second terminal of the storage inductor L1 and the control circuit 110. The control circuit 110 is also connected to the motor 200 (not shown) and controls the storage switch unit 131 to turn on according to the stopping condition of the motor 200.

[0049] Therefore, the control circuit 110 can acquire the operating status information of the motor 200 in real time. When the motor 200 stops running, the control circuit 110 sends a corresponding control command (such as a PWM signal) to the storage switch unit 131, controlling the storage switch unit 131 to quickly turn on. At this time, the motor 200, rectifier circuit 120, storage inductor L1, and storage switch unit 131 form a loop. The current output by the rectifier circuit 120 flows through the storage inductor L1, and the storage inductor L1 begins to store energy. As the current continues to flow in, the energy stored in the storage inductor L1 continuously accumulates, realizing the buffering of electrical energy.

[0050] In this embodiment, the storage inductor L1 can quickly respond to changes in current, achieving rapid energy buffering and effectively mitigating fluctuations in the induced electromotive force generated when the motor 200 stops. Since the induced electromotive force generated at the moment the motor 200 stops may fluctuate significantly, directly transferring this energy to the energy storage device 300 could damage it. The energy storage function of the storage inductor L1 smooths out the unstable energy, ensuring stable charging of the energy storage device 300 subsequently.

[0051] In some embodiments, such as Figure 4As shown, the charging switch circuit 140 includes a charging switch unit 141 and a switch drive unit 142. The switch drive unit 142 is connected to the control circuit 110 and the charging switch unit 141, and the charging switch unit 141 is connected to the energy buffer circuit 130 and the energy storage device 300. The control circuit 110 is used to control the charging switch unit to be turned on or off via the switch drive unit 142.

[0052] Specifically, when the motor stops running and the energy cache circuit 130 has stored a certain amount of electrical energy, requiring charging of the energy storage device 300, the controller 112 in the control circuit 110 outputs a conduction signal to the switch drive unit 142. Upon receiving this conduction signal, the switch drive unit 142 quickly amplifies the signal to enhance its driving capability of the charging switch unit 141. Subsequently, the amplified drive signal acts on the charging switch unit 141, turning it on. At this time, the electrical energy stored in the energy cache circuit 130 is transferred to the energy storage device 300 through the conducting charging switch unit 141, realizing the recovery and storage of electrical energy.

[0053] When the energy storage device 300 reaches full charge, or when the system detects an abnormality such as overvoltage, requiring the energy storage device 300 to stop charging, the controller 112 in the control circuit 110 will promptly output a disconnect signal to the switch drive unit 142. Similarly, the switch drive unit 142 amplifies the disconnect signal and applies it to the charging switch unit 141, controlling it to disconnect. The power transmission channel between the energy buffer circuit 130 and the energy storage device 300 is cut off, and the energy storage device 300 stops charging.

[0054] In this embodiment, the switch drive unit 142 enhances the driving capability of the on or off signal, enabling the charging switch unit 141 to reliably turn on and off. This improves the stability and reliability of the charging process, allowing the induced electromotive force generated when the motor stops running to be more stably and effectively recovered to the energy storage device 300, thus improving energy utilization.

[0055] Furthermore, the motor energy recovery circuit 100 may also include a freewheeling circuit 150. The first end of the freewheeling circuit 150 is connected to the energy buffer circuit 130, and the second end of the freewheeling circuit 150 is connected to the charging switch unit 141.

[0056] Specifically, the first end of the freewheeling circuit 150 is connected to the second end of the storage inductor L1 in the energy cache circuit 130, that is, the common end connecting the storage inductor L1 and the storage switch unit 131, and the second end of the freewheeling circuit 150 is connected to the charging switch unit 141.

[0057] When the motor 200 is running normally, the controller 112 controls the storage switch unit 131 and the switch drive unit 142 to disconnect, and at this time, no current flows through the freewheeling circuit 150. The instant the motor 200 stops running, the control circuit 110 quickly controls the storage switch unit 131 to turn on, causing the storage inductor L1 to begin storing energy, and the current in the storage inductor L1 gradually increases. However, due to the presence of inductive components in the circuit (such as the storage inductor L1), the current cannot change instantaneously according to the characteristics of inductance. Especially when the storage inductor L1 discharges and the state of the MOSFET in the storage switch unit 131 switches, a sudden current will occur, at which time the inductive component will generate a very high back electromotive force. This back electromotive force may damage various components in the circuit, such as the storage switch unit 131 and the charging switch unit 141, leading to a decrease in component performance or even damage, thereby affecting the normal operation of the entire motor energy recovery circuit 100.

[0058] In this embodiment, the freewheeling circuit 150 is used to freewheel current when the storage inductor L1 is discharging, providing a flow path for sudden current and charging flow, reducing the impact on circuit components and improving circuit safety.

[0059] The circuit structures of the storage switch unit 131, the charging switch unit 141, the switch drive unit 142, and the freewheeling circuit 150 can be configured according to actual conditions. In some embodiments, such as Figure 5 As shown, the storage switch unit 131 includes a first MOS transistor (i.e., a MetalOxide Semiconductor Field Effect Transistor) Q1. The first terminal of the first MOS transistor Q1 is connected to the second terminal of the storage inductor L1, the second terminal of the first MOS transistor Q1 is grounded, and the gate of the first MOS transistor Q1 is connected to the control circuit 110.

[0060] The first MOSFET Q1 is used to control the charging of the storage inductor L1, and its type can be selected according to the actual situation. As an example, the first MOSFET Q1 is an N-type MOSFET, with the drain as the first terminal and the source as the second terminal.

[0061] In some embodiments, the charging switch unit 141 includes a second MOSFET Q2 and a first resistor R1. The first terminal of the second MOSFET Q2 is connected to the energy cache circuit 130, the second terminal of the second MOSFET Q2 is connected to the energy storage device 300, and the gate of the second MOSFET Q2 is connected to the control circuit 110; the first terminal of the first resistor R1 is connected to the first terminal of the second MOSFET Q2, and the second terminal of the first resistor R1 is connected to the gate of the second MOSFET Q2.

[0062] The second MOSFET Q2 is used to control the charging of the energy storage device 300 when the storage inductor L1 discharges. Its type can be selected according to actual conditions. As an example, the second MOSFET Q2 is a P-type MOSFET, with its source as the first terminal and its drain as the second terminal. It can be understood that in this embodiment, the energy storage device 300 includes a capacitor C1. The first terminal of capacitor C1 is connected to the second terminal of the second MOSFET Q2, and the second terminal of capacitor C1 is grounded. Capacitor C1 can be a gold capacitor or other capacitor used for energy storage. The first resistor R1 is a bias resistor to prevent the second MOSFET Q2 from mis-conducting and improve charging reliability.

[0063] In some embodiments, the switch driving unit 142 includes a transistor Q0, a second resistor R2, and a third resistor R3. The first end of the second resistor R2 is connected to the control circuit 110, the second end of the second resistor R2 is connected to the base of the transistor Q0 and the first end of the third resistor R3, the emitter of the transistor Q0 and the second end of the third resistor R3 are grounded, and the collector of the transistor Q0 is connected to the gate of the second MOSFET Q2.

[0064] The transistor Q0 amplifies the turn-on and turn-off signals output by the control chip in the control circuit 110 to improve signal driving capability, thereby effectively controlling the state switching of the second MOSFET Q2. The second resistor R2 is a current-limiting resistor used to limit the base current of transistor Q0. The third resistor R3 is a bias resistor to prevent transistor Q0 from being mis-turned on. This improves the reliability of transistor Q0's operation, thereby improving the reliability of the second MOSFET Q2's operation and charging reliability.

[0065] In some embodiments, the freewheeling circuit 150 includes a third MOSFET Q3. The first terminal of the third MOSFET Q3 is connected to the charging switch unit 141, the second terminal of the third MOSFET Q3 is connected to the energy cache circuit 130, and the gate of the third MOSFET Q3 is connected to the common terminal of the charging switch unit 141 and the switch driving unit 142.

[0066] The third MOSFET, Q3, is used to freewheel the current when the storage inductor L1 discharges, improving circuit safety. As an example, the third MOSFET, Q3, is a P-type MOSFET, with its source as the first terminal and its drain as the second terminal.

[0067] In an optional embodiment, the third MOSFET Q3 can be replaced with a freewheeling diode, the anode of which is connected to the second terminal of the storage inductor L1, and the cathode of which is connected to the charging switch unit 141.

[0068] In some embodiments, the rectifier circuit 120 includes a rectifier diode D1. The anode of the rectifier diode D1 is connected to the motor 200, and the cathode of the rectifier diode D1 is connected to the energy buffer circuit 130.

[0069] Specifically, the cathode of rectifier diode D1 is connected to the first terminal of storage inductor L1. Rectifier diode D1 is used to rectify the alternating current induced electromotive force generated by the rotor of motor 200 cutting magnetic field lines after the motor 200 stops running into a direct current voltage, forming a direct current that can be used for energy storage, thereby realizing energy recovery and improving energy utilization.

[0070] To better understand the above embodiments, an optional embodiment will be explained in detail below. Please refer to... Figures 1-5 In one embodiment, the motor energy recovery circuit 100 includes a control circuit 110, a rectifier circuit 120, an energy buffer circuit 130, a charging switch circuit 140, and a freewheeling circuit 150. The control circuit 110 includes a sampling unit 111 and a controller 112. The rectifier circuit 120 includes a rectifier diode D1. The energy buffer circuit 130 includes a storage inductor L1 and a storage switch unit 131, which includes a first MOSFET Q1. The charging switch circuit 140 includes a charging switch unit 141 and a switch driving unit 142. The charging switch unit 141 includes a second MOSFET Q2 and a first resistor R1. The switch driving unit 142 includes a transistor Q0, a second resistor R2, and a third resistor R3. The freewheeling circuit 150 includes a third MOSFET Q3.

[0071] After motor 200 stops running, its rotor continues to rotate due to inertia, cutting magnetic field lines and generating an induced electromotive force (EMF). This EMF is an AC voltage. This AC voltage is rectified into a DC voltage by rectifier diode D1, forming a DC current that can be used for energy storage.

[0072] The controller 112 outputs a PWM (Pulse Width Modulation) signal based on the stopped operating condition of the motor 200, driving the first MOSFET Q1 to turn on, causing the storage inductor L1 to start storing energy. The controller 112 detects the energy storage voltage of the storage inductor L1 through the sampling unit 111.

[0073] When the controller 112 detects that the energy stored in the storage inductor L1 has reached the set value, it outputs a high-level signal to the port connected to the second resistor R2, triggering the transistor Q0 to conduct. At this time, the third MOSFET Q3 is turned off, and the second MOSFET Q2 is turned on. The energy stored in the storage inductor L1 charges the gold capacitor C1 through the circuit formed by the body diode of the third MOSFET Q3 and the second MOSFET Q2, thereby achieving effective energy recovery.

[0074] The aforementioned motor energy recovery circuit 100 achieves efficient switching of energy recovery paths, avoids energy waste, and improves the overall energy efficiency of the system.

[0075] This application also provides an electrical appliance; in some embodiments, please refer again. Figure 1The electrical equipment includes a motor 200, an energy storage device 300, and a motor energy recovery circuit 100. The electronic equipment may include, but is not limited to, fans, range hoods, dishwashers, etc. The motor energy recovery circuit 100 is used to recover the induced electromotive force generated when the rotor of the motor 200 cuts magnetic field lines due to inertia during the stationary phase, and transfer it to the energy storage device 300. The energy storage device 300 can be a battery or a gold capacitor, or other device capable of storing electrical energy.

[0076] The motor energy recovery circuit 100 includes a control circuit 110, a rectifier circuit 120, an energy buffer circuit 130, and a charging switch circuit 140. The rectifier circuit 120 is connected to the motor 200 to rectify the induced electromotive force generated by the motor 200 when it is not running. The energy buffer circuit 130 is connected to the rectifier circuit 120 and stores the rectified electrical energy output from the rectifier circuit 120. The charging switch circuit 140 is connected to the energy buffer circuit 130, the energy storage device 300, and the control circuit 110. The control circuit 110 controls the charging switch circuit 140 to conduct, transferring the electrical energy stored in the energy buffer circuit 130 to the energy storage device 300.

[0077] In some embodiments, the control circuit 110 is also connected to the energy cache circuit 130, and is capable of sampling the stored energy of the energy cache circuit 130 and controlling the charging switch circuit 140 to turn on based on the stored energy of the energy cache circuit 130. As an example, the control circuit 110 controls the charging switch circuit 140 to turn on when the stored energy of the energy cache circuit 130 is greater than or equal to a preset voltage threshold. The preset voltage threshold can be set according to actual conditions, such as based on the performance parameters of the energy storage device 300.

[0078] In some embodiments, such as Figure 2 As shown, the control circuit 110 includes a sampling unit 111 and a controller 112. The sampling unit 111 is connected to the energy cache circuit 130 and the controller 112. The controller 112 is used to control the charging switch circuit 140 according to the stored power of the energy cache circuit 130 sampled by the sampling unit 111.

[0079] In some embodiments, such as Figure 3 As shown, the energy buffer circuit 130 includes a storage inductor L1 and a storage switch unit 131. The first terminal of the storage inductor L1 is connected to the rectifier circuit 120, and the second terminal of the storage inductor L1 is connected to the charging switch circuit 140. The storage switch unit 131 is connected to the second terminal of the storage inductor L1 and the control circuit 110. The control circuit 110 is also connected to the motor 200 (not shown) and controls the storage switch unit 131 to turn on according to the stopping condition of the motor 200.

[0080] In some embodiments, such as Figure 4 As shown, the charging switch circuit 140 includes a charging switch unit 141 and a switch drive unit 142. The switch drive unit 142 is connected to the control circuit 110 and the charging switch unit 141, and the charging switch unit 141 is connected to the energy buffer circuit 130 and the energy storage device 300. The control circuit 110 is used to control the charging switch unit to be turned on or off via the switch drive unit 142.

[0081] In some embodiments, the motor energy recovery circuit 100 may further include a freewheeling circuit 150. The first end of the freewheeling circuit 150 is connected to the energy buffer circuit 130, and the second end of the freewheeling circuit 150 is connected to the charging switch unit 141.

[0082] In some embodiments, the charging switch unit 141 includes a second MOSFET Q2 and a first resistor R1. The first terminal of the second MOSFET Q2 is connected to the energy cache circuit 130, the second terminal of the second MOSFET Q2 is connected to the energy storage device 300, and the gate of the second MOSFET Q2 is connected to the control circuit 110; the first terminal of the first resistor R1 is connected to the first terminal of the second MOSFET Q2, and the second terminal of the first resistor R1 is connected to the gate of the second MOSFET Q2.

[0083] In some embodiments, the switch driving unit 142 includes a transistor Q0, a second resistor R2, and a third resistor R3. The first end of the second resistor R2 is connected to the control circuit 110, the second end of the second resistor R2 is connected to the base of the transistor Q0 and the first end of the third resistor R3, the emitter of the transistor Q0 and the second end of the third resistor R3 are grounded, and the collector of the transistor Q0 is connected to the gate of the second MOSFET Q2.

[0084] In some embodiments, the freewheeling circuit 150 includes a third MOSFET Q3. The first terminal of the third MOSFET Q3 is connected to the charging switch unit 141, the second terminal of the third MOSFET Q3 is connected to the energy cache circuit 130, and the gate of the third MOSFET Q3 is connected to the common terminal of the charging switch unit 141 and the switch driving unit 142.

[0085] In an optional embodiment, the third MOSFET Q3 can be replaced with a freewheeling diode, the anode of which is connected to the second terminal of the storage inductor L1, and the cathode of which is connected to the charging switch unit 141.

[0086] In some embodiments, the rectifier circuit 120 includes a rectifier diode D1. The anode of the rectifier diode D1 is connected to the motor 200, and the cathode of the rectifier diode D1 is connected to the energy buffer circuit 130.

[0087] In the aforementioned electronic device, the energy recovery circuit 100 is incorporated to recover the energy generated when the motor is not running, thus preventing energy waste. Furthermore, this energy can be used to power other circuits in the electronic device when needed, thereby improving the overall energy efficiency of the device.

[0088] In the description of this specification, references to terms such as "some embodiments," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0089] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0090] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. An electric machine energy recovery circuit, characterized by, include: Control circuit; A rectifier circuit is used to connect to the motor and rectify the induced electromotive force generated by the motor when it is stopped. An energy buffer circuit is connected to the rectifier circuit, and the energy buffer circuit is used to store the rectified electrical energy output by the rectifier circuit; A charging switch circuit is connected to the energy buffer circuit, the control circuit, and the energy storage device; the control circuit controls the charging switch circuit to turn on so as to transfer the electrical energy stored in the energy buffer circuit to the energy storage device.

2. The motor energy recovery circuit of claim 1, wherein, The energy buffer circuit includes: A storage inductor, wherein a first end of the storage inductor is connected to the rectifier circuit, and a second end of the storage inductor is connected to the charging switch circuit; A storage switch unit is provided, which is connected to the second terminal of the storage inductor and the control circuit. The control circuit is also connected to the motor and controls the storage switch unit to turn on according to the motor's stop operation condition.

3. The motor energy recovery circuit of claim 2, wherein, The storage switching unit includes a first MOS transistor; the first terminal of the first MOS transistor is connected to the second terminal of the storage inductor, the second terminal of the first MOS transistor is grounded, and the gate of the first MOS transistor is connected to the control circuit.

4. The motor energy recovery circuit of claim 1, wherein, The charging switch circuit includes a charging switch unit and a switch driving unit; the switch driving unit is connected to the control circuit and the charging switch unit, and the charging switch unit is connected to the energy buffer circuit and the energy storage device; the control circuit controls the charging switch unit through the switch driving unit.

5. The motor energy recovery circuit of claim 4, wherein, The charging switch unit includes a second MOSFET and a first resistor; the first terminal of the second MOSFET is connected to the energy cache circuit, the second terminal of the second MOSFET is connected to the energy storage device, and the gate of the second MOSFET is connected to the control circuit; the first terminal of the first resistor is connected to the first terminal of the second MOSFET, and the second terminal of the first resistor is connected to the gate of the second MOSFET.

6. The motor energy recovery circuit of claim 5, wherein, The switch driving unit includes a transistor, a second resistor, and a third resistor; the first end of the second resistor is connected to the control circuit, the second end of the second resistor is connected to the base of the transistor and the first end of the third resistor, the emitter of the transistor and the second end of the third resistor are grounded, and the collector of the transistor is connected to the gate of the second MOS transistor.

7. The motor energy recovery circuit of claim 4, wherein, It also includes a freewheeling circuit; the first end of the freewheeling circuit is connected to the energy buffer circuit, and the second end of the freewheeling circuit is connected to the charging switch unit.

8. The motor energy recovery circuit of claim 7, wherein, The freewheeling circuit includes a third MOSFET; the first terminal of the third MOSFET is connected to the charging switch unit, the second terminal of the third MOSFET is connected to the energy cache circuit, and the gate of the third MOSFET is connected to the common terminal of the charging switch unit and the switch driving unit.

9. The motor energy recovery circuit of claim 1, wherein, The rectifier circuit includes a rectifier diode; the anode of the rectifier diode is connected to the motor, and the cathode of the rectifier diode is connected to the energy buffer circuit.

10. The motor energy recovery circuit of claim 1, wherein, The control circuit includes a sampling unit and a controller; the sampling unit is connected to the energy cache circuit and the controller, and the controller controls the charging switch circuit according to the stored power of the energy cache circuit obtained by the sampling unit.

11. An electrical device, characterized by include: The electric motor, the energy storage device, and the electric motor energy recovery circuit as described in any one of claims 1-10.

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