Sampling circuit, variable frequency driver and clothes processing equipment
By introducing a switching circuit into the bus voltage sampling circuit to control its on and off states, the standby power consumption problem is solved, the sampling circuit achieves low power consumption and circuit simplicity, and the stability of the equipment is improved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- NANJING ROBOROCK INNOVATION TECH CO LTD
- Filing Date
- 2025-03-25
- Publication Date
- 2026-04-28
AI Technical Summary
In the existing technology, the bus voltage sampling circuit of the frequency converter driver has a power consumption problem in the standby state, and adding a rectifier circuit will increase the circuit complexity.
A switching circuit is introduced into the bus voltage sampling circuit. By controlling the on and off states of the switching circuit, the bus voltage is sampled when it is on and sampling stops when it is off, thus avoiding power consumption.
This effectively reduces the standby power consumption of the sampling circuit while avoiding increased circuit complexity, thus improving the stability and reliability of the device.
Smart Images
Figure CN224176619U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of household appliance technology, and more particularly to a sampling circuit, a frequency converter, and a clothing processing device. Background Technology
[0002] Currently, brushless direct current motors (BLDC) and direct drive motors are increasingly widely used in washing machines and dryers. For the sampling circuit of the bus voltage of the inverter driver driving the motor, which has always been a component of standby power consumption, there is still room for improvement. Summary of the Invention
[0003] In view of this, embodiments of this application provide at least one sampling circuit, a frequency converter driver, and a garment processing device. This reduces the power consumption of the sampling circuit.
[0004] The technical solution of this application embodiment is implemented as follows:
[0005] In a first aspect, embodiments of this application provide a sampling circuit for acquiring bus voltage, which supplies power to a motor's frequency converter and a switching power supply. The sampling circuit includes a voltage divider circuit, a switching circuit, and a data acquisition device. The switching circuit is disposed within the voltage divider circuit, and the data acquisition device is connected to the acquisition point of the voltage divider circuit.
[0006] When the switching circuit is in the ON state, the branch where the voltage divider circuit is located is turned on, and the acquisition device acquires the voltage at the acquisition point of the voltage divider circuit to obtain the bus voltage.
[0007] When the switching circuit is in the open state, the branch containing the voltage divider circuit is disconnected.
[0008] Secondly, embodiments of this application provide a variable frequency drive, including the sampling circuit described in one or more of the above embodiments, wherein the bus voltage collected by the sampling circuit is used to power the variable frequency drive for driving a motor.
[0009] Thirdly, this application provides a garment processing device, including: a sampling circuit, a motor, and a frequency converter driver as described in one or more of the above embodiments. The frequency converter driver drives the motor under the power supply of the bus voltage to enable the garment processing device to operate.
[0010] This application provides a sampling circuit, a frequency converter driver, and a garment processing device. The sampling circuit is used to collect bus voltage, which powers the frequency converter driver and the switching power supply. The sampling circuit includes a voltage divider circuit, a switching circuit, and a data acquisition device. The switching circuit is located within the voltage divider circuit, and the data acquisition device is connected to the collection point of the voltage divider circuit. When the switching circuit is in the ON state, it conducts the branch of the voltage divider circuit, and the data acquisition device collects the voltage at the collection point of the voltage divider circuit to obtain the bus voltage. When the switching circuit is in the OFF state, it disconnects the branch of the voltage divider circuit. In other words, in this application embodiment, by setting a switching circuit in the voltage divider circuit of the bus voltage sampling circuit, the branch of the voltage divider circuit is conducted when the switching circuit is in the ON state, so that the data acquisition device obtains the bus voltage by collecting the voltage at the collection point. When the switching circuit is in the OFF state, the branch of the voltage divider circuit is disconnected, so that the sampling circuit does not generate power consumption in standby mode. Thus, by setting the switching circuit, the power consumption of the sampling circuit is reduced. Attached Figure Description
[0011] Figure 1 This is a schematic diagram of the sampling circuit in the related technology;
[0012] Figure 2 A schematic diagram of an optional sampling circuit provided in an embodiment of this application;
[0013] Figure 3 A schematic diagram illustrating an example of an optional sampling circuit provided in this application embodiment;
[0014] Figure 4 A schematic diagram of an optional frequency converter driver provided in an embodiment of this application;
[0015] Figure 5 This is a schematic diagram of an optional garment processing device provided in an embodiment of this application. Detailed Implementation
[0016] To make the technical solutions and advantages of this application clearer, the technical solutions of this application are further described in detail below with reference to the accompanying drawings and embodiments. The described embodiments should not be regarded as limitations on this application. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0017] In the following description, references to "some embodiments" refer to a subset of all possible embodiments. It is understood that "some embodiments" may be the same or different subsets of all possible embodiments and may be combined with each other without conflict. The terms "first / second / third" are used merely to distinguish similar objects and do not represent a specific ordering of objects. It is understood that "first / second / third" may be interchanged in a specific order or sequence where permitted, so that the embodiments of this application described herein can be implemented in an order other than that illustrated or described herein.
[0018] 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 embodiments of this application only and is not intended to limit the scope of this application.
[0019] Typically, to reduce the power consumption caused by the bus voltage sampling circuit, when the equipment containing the motor enters standby mode, the standby power consumption can be reduced by cutting off the bus voltage or by adding a rectifier circuit to the switching power supply.
[0020] However, the aforementioned method of cutting off the bus voltage will affect the operation of the switching power supply. In addition, adding a rectifier circuit to the switching power supply will increase the complexity of the circuit.
[0021] Figure 1 This is a schematic diagram of the sampling circuit in related technologies, such as... Figure 1 As shown, the sampling circuit 100 may include: R10, R11, R12, R13, R14 and C1; wherein, one end of R10 is connected to the bus voltage VBUS, the other end of R10 is connected to one end of R11, the other end of R11 is connected to one end of R12, one end of R12 is connected to one end of R13 and one end of R14 respectively, the other end of R13 is connected to one end of C1, the other ends of R14 and the other ends of C1 are grounded, one end of C1 is the sampling point, the sampled voltage is recorded as VBUS-AD, and after obtaining VBUS-AD, VBUS can be obtained.
[0022] VBUS supplies power to the motor's frequency converter driver and switching power supply. When the device with VBUS is in standby mode, the sampling circuit will generate power consumption if it continues to work. If VBUS is turned off, it will be unable to provide voltage to the switching power supply, thus causing the device with VBUS to malfunction.
[0023] Alternatively, by adding a rectifier circuit to the front end of VBUS, the device containing VBUS can operate normally in standby mode and the sampling circuit can be kept power-free. However, this method increases the complexity of the rectifier circuit.
[0024] To address the technical problem that reducing power consumption in bus voltage sampling circuits increases circuit complexity, this application provides a sampling circuit for acquiring bus voltage, which is used to power the frequency converter driver and switching power supply of the motor. Figure 2 A schematic diagram of an optional sampling circuit provided in an embodiment of this application is shown below. Figure 2 As shown, the sampling circuit 200 may include:
[0025] The system comprises a voltage divider circuit 21, a switching circuit 22, and a data acquisition device 23; wherein the switching circuit 22 is disposed within the voltage divider circuit 21, and the data acquisition device 23 is connected to the data acquisition point of the voltage divider circuit 21; wherein,
[0026] When the switching circuit 22 is in the conducting state, the branch where the voltage divider circuit 21 is located is turned on, and the acquisition device 23 acquires the voltage at the acquisition point of the voltage divider circuit 21 to obtain the bus voltage.
[0027] When the switching circuit 22 is in the open state, the branch containing the voltage divider circuit 21 is disconnected.
[0028] In this embodiment, the sampling circuit 200 collects the bus voltage used to power the motor's frequency converter and switching power supply, respectively. Therefore, it can be seen that VBUS is connected to the motor's frequency converter, switching power supply, and sampling circuit 200, respectively.
[0029] Specifically, for the sampling circuit 200, one end of the voltage divider circuit 21 of the sampling circuit 200 is connected to VBUS, and the acquisition point of the voltage divider circuit 21 is connected to the acquisition device 23. In this embodiment, the switch circuit 22 is set in the voltage divider circuit 21. Here, the two ends of the switch circuit 22 can be connected to the voltage divider connection point of the voltage divider circuit 21. For example, when the voltage divider circuit 22 is composed of at least two voltage divider resistors connected in series, the switch circuit 22 can be set between the two connected voltage divider resistors.
[0030] The switching circuit 22 described above can include two states: an on state and an off state. In this embodiment, when the switching circuit 22 is in the on state, the voltage divider circuit 21 is in the on state, so that the acquisition device 23 can acquire the voltage at the acquisition point, thereby obtaining the bus voltage VBUS through the voltage at the acquisition point, and thus achieving the purpose of the sampling circuit 200 to acquire VBUS.
[0031] The switching circuit 22 can also be in the open state. When the switching circuit 22 is in the open state, the voltage divider circuit 21 is in the open state. At this time, the acquisition device 23 cannot acquire the voltage at the acquisition point, and therefore cannot know the bus voltage, thus causing the sampling circuit 200 to not work.
[0032] In other words, in order to ensure that the bus voltage sampling circuit does not generate power consumption when the device is in standby mode, the control switch circuit 22 is in the open state when the device is in standby mode, thereby disconnecting the branch where the voltage divider circuit 21 is located, so that the acquisition device 23 cannot acquire the voltage at the acquisition point, and thus the sampling circuit 200 cannot acquire the bus voltage.
[0033] When the equipment where the bus voltage is located is working normally, the control switch circuit 22 is in the conducting state, thereby turning on the branch where the voltage divider circuit 21 is located, so that the acquisition device 23 can acquire the voltage at the acquisition point, and thus the sampling circuit 200 can sample the bus voltage.
[0034] The switching circuit 22 can be turned on or off using a control circuit, or the processor of the device where the bus voltage is located can be used to control the switching circuit 22. However, this application embodiment does not specifically limit this.
[0035] The aforementioned switch circuit 22 can be implemented using a control-type switch, a control-type device, or a switch circuit composed of multiple devices. Here, the embodiments of this application do not specifically limit this.
[0036] In order for the switching circuit to perform the function of turning on or off the voltage divider circuit as described above, in an optional embodiment, the switching circuit includes a switching transistor.
[0037] Understandably, a switching transistor, as an electronic component, is mainly used to control the current flow in a circuit. It quickly switches between current flow and dielectric states via an external signal, thereby achieving circuit opening and closing control. Here, the switching transistor is used as a switching circuit to turn on or off a voltage divider circuit, thus enabling the voltage divider circuit to conduct or disconnect.
[0038] The aforementioned switching transistor can be a metal-oxide-semiconductor field-effect transistor (MOSFET), an insulated-gate bipolar transistor (IGBT), a bipolar junction transistor (BJT), or a silicon controlled rectifier (SCR); however, this application embodiment does not specifically limit this.
[0039] Thus, by using the aforementioned switching transistor to achieve the function of the switching circuit, the voltage divider circuit can be switched between the on and off states by controlling the control terminal of the switching transistor, so that the sampling circuit does not generate power consumption during standby.
[0040] Furthermore, in order to realize the function of the switching circuit, in one optional embodiment, the switching transistor is a MOSFET; the gate of the MOSFET is connected to the driving power supply of the MOSFET.
[0041] Understandably, the aforementioned switching transistor can be a MOSFET. As is well known, a MOSFET is a gate-driven switching transistor. Therefore, the gate of the MOSFET is connected to the MOSFET's driving power supply. In this way, the on or off state of the MOSFET can be controlled by controlling the MOSFET's driving power supply, thereby making the switching circuit in the on or off state.
[0042] It should be noted that when using the aforementioned MOSFET, resistors and / or diodes can also be used together with the switching transistor to form a switching circuit, thereby improving the safety and reliability of the switching circuit.
[0043] Thus, by using the aforementioned MOSFET to implement the switching circuit, the switching transistor can be turned on or off by controlling the drive power supply of the MOSFET's gate, so as not to generate power consumption of the sampling circuit during standby.
[0044] In addition, for the aforementioned MOSFET, in one optional embodiment, the drain-source breakdown voltage of the MOSFET is greater than the bus voltage.
[0045] Understandably, as is well known, the drain-source breakdown voltage (BVdss) of a MOSFET is a key parameter defining its ability to withstand high voltages. It represents the maximum voltage that the drain and source can withstand when the gate and source are short-circuited. Exceeding this voltage will cause irreversible damage to the device.
[0046] Here, the drain-source breakdown voltage of the MOSFET is greater than the bus voltage, so that the MOSFET will not be damaged even when it is subjected to the bus voltage, thus ensuring that the sampling circuit is more stable and reliable.
[0047] Furthermore, the aforementioned MOS transistor can be a PMOS transistor or an NMOS transistor. In the case where the aforementioned MOS transistor is a PMOS transistor, in an optional embodiment, the MOS transistor is a PMOS transistor; wherein, the source of the PMOS transistor is connected to one end of the first voltage divider resistor of the voltage divider circuit, and the drain of the PMOS transistor is connected to one end of the second voltage divider circuit of the voltage divider circuit.
[0048] Understandably, when a PMOS transistor is used as a switching circuit, the voltage divider circuit includes at least a first voltage divider resistor and a second voltage divider resistor. The source of the PMOS transistor is connected to one end of the first voltage divider resistor, and the drain of the PMOS transistor is connected to one end of the second voltage divider resistor. When the sampling circuit is working, the voltage at the other end of the first voltage divider resistor is higher than the voltage at the other end of the second voltage divider resistor.
[0049] In other words, the source of the PMOS transistor is connected to the end with a higher voltage than the drain of the PMOS transistor. This allows current to flow from the source to the drain of the PMOS transistor when the gate drive voltage meets the conduction condition, ensuring that the sampling circuit can collect the bus voltage when working normally.
[0050] In one optional embodiment, where the MOS transistor is an NMOS transistor, the drain of the NMOS transistor is connected to one end of the first voltage divider resistor in the voltage divider circuit, and the source of the NMOS transistor is connected to one end of the second voltage divider circuit in the voltage divider circuit.
[0051] Understandably, when an NMOS transistor is used as a switching circuit, the voltage divider circuit includes at least a first voltage divider resistor and a second voltage divider resistor. The drain of the NPMOS transistor is connected to one end of the first voltage divider resistor, and the source of the PMOS transistor is connected to one end of the second voltage divider resistor. When the sampling circuit is working, the voltage at the other end of the first voltage divider resistor is higher than the voltage at the other end of the second voltage divider resistor.
[0052] In other words, the drain of an NMOS transistor is connected to a higher voltage terminal than the source of a PMOS transistor. This allows current to flow from the drain to the source of the NMOS transistor when the gate drive voltage meets the conduction condition, ensuring that the sampling circuit can acquire the bus voltage during normal operation.
[0053] In the case where the switching transistor is a MOSFET, in order to improve the performance of the switching circuit, in an optional embodiment, the switching circuit further includes a discharge resistor; wherein one end of the discharge circuit is connected to the gate of the MOSFET, and the other end of the discharge resistor is grounded.
[0054] Understandably, the above-mentioned switching circuit may include a discharge resistor in addition to the MOSFET. The discharge resistor is connected between the gate of the MOSFET and ground. For a PMOS transistor, it can be used to release the charge in the parasitic capacitance between the gate and drain of the PMOS transistor. For an NMOS transistor, it can be used to release the charge in the parasitic capacitance between the gate and source of the PMOS transistor.
[0055] Thus, by setting a discharge resistor between the gate and ground of the MOSFET, a discharge circuit for the parasitic capacitance is established, which facilitates the discharge of the parasitic capacitance and enables the MOSFET to be reliably turned off.
[0056] In addition, to better control the conduction or disconnection of the MOSFET, in one optional embodiment, the switching circuit further includes a current-limiting resistor; wherein one end of the current-limiting resistor is connected to the gate of the MOSFET, and the other end of the current-limiting resistor is connected to the driving power supply.
[0057] Understandably, in addition to the MOSFET, the above-mentioned switching circuit may also include a current-limiting resistor connected between the gate of the MOSFET and the driving power supply, for voltage division and current limiting of the circuit between the driving power supply and the gate.
[0058] Here, the appropriate value of the current-limiting resistor can be selected based on the size of the driving power supply, thereby enabling control of the gate of the MOSFET through the driving power supply and the current-limiting resistor.
[0059] In this way, the driving power supply controls the gate of the MOSFET through the current-limiting resistor, thereby turning the MOSFET on or off, which helps to improve the performance of the switching circuit.
[0060] To improve the reliability of the switching circuit, in one optional embodiment, the switching circuit further includes a diode; wherein the anode of the diode is connected to the driving power supply, and the cathode of the diode is connected to the gate of the MOSFET.
[0061] Understandably, the above-mentioned switching circuit may include a diode in addition to a MOSFET, connected between the gate of the MOSFET and the driving power supply. Since the diode has unidirectional conductivity, it can cut off the bus voltage on the sampling circuit and play a protective role.
[0062] In this way, the driving power supply controls the gate of the MOSFET through the diode, thereby cutting off the bus voltage on the sampling circuit, which plays a protective role and helps to improve the performance of the switching circuit.
[0063] In addition to using a diode to prevent high voltage, in an optional embodiment, the switching circuit further includes a current-limiting resistor; wherein one end of the current-limiting resistor is connected to the anode of the diode, and the other end of the current-limiting resistor is connected to the drive power supply.
[0064] Understandably, in addition to diodes, the aforementioned switching circuit may also include a current-limiting resistor, which is placed between the anode of the diode and the driving power supply to perform voltage division and current limiting on the circuit between the driving power supply and the diode.
[0065] Here, the appropriate value of the current-limiting resistor can be selected based on the size of the driving power supply, so that the gate of the MOSFET can be controlled through the driving power supply, the current-limiting resistor and the diode.
[0066] In this way, the driving power supply controls the gate of the MOSFET through the current-limiting resistor and diode, thereby turning the MOSFET on or off, which helps to improve the performance of the switching circuit.
[0067] The following examples illustrate the sampling circuit described in one or more of the above embodiments.
[0068] Given that in related technologies, when the equipment with the bus voltage is in standby mode, cutting off the bus voltage rectifier will cause other parts of the equipment to fail to standby, it is necessary to add a separate rectifier circuit for the switching power supply. However, this not only increases the cost of the circuit, but also increases the complexity and difficulty of the circuit design, and increases the standby power consumption problem for application scenarios where the bus voltage cannot be cut off.
[0069] In this example, without disconnecting the bus voltage rectifier circuit, only a MOSFET and simple peripheral circuit are added. The MOSFET is turned on during normal sampling and turned off during standby. This achieves the goal of reducing the power consumption of the bus voltage sampling circuit by disconnecting the bus voltage sampling circuit during standby, while the bus voltage rectifier circuit remains in operation.
[0070] Figure 3 A schematic diagram illustrating an example of an optional sampling circuit provided in this application embodiment, as shown below. Figure 3 As shown, the sampling circuit 300 may include: R10, R11, R12, R13, R14, R15, R16, C1, Q1, and D1; wherein, Q1 is a PMOS transistor, D1 is a diode, one end of R10 is connected to the bus voltage VBUS, the other end of R10 is connected to one end of R11, the other end of R11 is connected to one end of R12, the other end of R12 is connected to the source terminal 3 of Q1, one end of R13 is connected to the drain terminal 2 of Q1 and one end of R14 respectively, the other end of R13 is the sampling point and is connected to one end of C1, the other end of C1 and the other end of R14 are both grounded.
[0071] The switching circuit may include Q1, R15, R16 and D1. The gate 1 of Q1 is connected to one end of R16 and the cathode of D1. The other end of R16 is grounded. The anode of D1 is connected to one end of R15. The other end of R15 is connected to VCC.
[0072] Here, VBUS represents the bus voltage, and VCC represents the drive voltage of Q1. This voltage can be turned off in standby mode. During normal operation, VCC turns on Q1 through R15 and D1, and the VBUS sampling circuit normally acquires the bus voltage. When VCC voltage is 0, Q1 is turned off, and the VBUS sampling circuit is cut off. At this time, VBUS still exists, but the sampling circuit is not working. This reduces the power consumption of the sampling circuit in standby mode. The MOSFET is a high-voltage MOSFET, which improves the stability and reliability of the sampling circuit.
[0073] As can be seen, the sampling circuit in the above example has a simple circuit structure and is easy to implement, reducing the complexity of the product. The product is reliable and stable, reducing the cost of hardware design.
[0074] This application provides a sampling circuit for acquiring bus voltage, which powers the frequency converter driver and switching power supply of the motor. The sampling circuit includes a voltage divider circuit, a switching circuit, and a data acquisition device. The switching circuit is located within the voltage divider circuit, and the data acquisition device is connected to the acquisition point of the voltage divider circuit. When the switching circuit is in the ON state, it conducts the branch of the voltage divider circuit, and the data acquisition device acquires the voltage at the acquisition point of the voltage divider circuit to obtain the bus voltage. When the switching circuit is in the OFF state, it disconnects the branch of the voltage divider circuit. In other words, in this application embodiment, by setting a switching circuit in the voltage divider circuit of the bus voltage sampling circuit, the branch of the voltage divider circuit is conducted when the switching circuit is in the ON state, so that the data acquisition device acquires the bus voltage by acquiring the voltage at the acquisition point. When the switching circuit is in the OFF state, the branch of the voltage divider circuit is disconnected, so that the sampling circuit does not generate power consumption in standby mode. Thus, by setting the switching circuit, the power consumption of the sampling circuit is reduced.
[0075] Based on the same inventive concept, this application also provides a frequency converter driver. Figure 4 A schematic diagram of an optional frequency converter driver provided in an embodiment of this application is shown below. Figure 4 As shown, the bus voltage collected by the sampling circuit 41 in one or more of the above embodiments is used to power the frequency converter 400 for driving the motor 42.
[0076] This application also provides a garment processing device. Figure 5 A schematic diagram of an optional garment processing device provided in an embodiment of this application is shown below. Figure 5 As shown, the garment processing equipment 500 includes: a sampling circuit 41 as described in one or more of the above embodiments, a motor 42, and a frequency converter 400 as described in one or more of the above embodiments. The frequency converter 400 drives the motor 42 under the power supply of the bus voltage, so that the garment processing equipment 500 can operate.
[0077] The aforementioned clothing processing equipment 500 can be a washing machine, dryer, or washer-dryer combo.
[0078] The computer-readable storage medium can be a magnetic random access memory (FRAM), a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a flash memory, a magnetic surface memory, an optical disc, or a compact disc read-only memory (CD-ROM), etc.
[0079] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of hardware embodiments, software embodiments, or embodiments combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.
[0080] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.
[0081] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.
[0082] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.
[0083] The above description is merely an optional embodiment of this application and is not intended to limit the scope of protection of this application.
Claims
1. A sampling circuit, characterized in that, The sampling circuit is used to acquire the bus voltage, which supplies power to the motor's frequency converter and switching power supply. The sampling circuit includes a voltage divider circuit, a switching circuit, and a data acquisition device. The switching circuit is integrated within the voltage divider circuit, and the data acquisition device is connected to the acquisition point of the voltage divider circuit. When the switching circuit is in the ON state, the branch where the voltage divider circuit is located is turned on, and the acquisition device acquires the voltage at the acquisition point of the voltage divider circuit to obtain the bus voltage. When the switching circuit is in the open state, the branch containing the voltage divider circuit is disconnected.
2. The sampling circuit according to claim 1, characterized in that, The switching circuit includes a switching transistor.
3. The sampling circuit according to claim 2, characterized in that, The switching transistor is a MOSFET; the gate of the MOSFET is connected to the driving power supply of the MOSFET.
4. The sampling circuit according to claim 3, characterized in that, The drain-source breakdown voltage of the MOS transistor is greater than the bus voltage.
5. The sampling circuit according to claim 3, characterized in that, The MOS transistor is a PMOS transistor; wherein, the source of the PMOS transistor is connected to one end of the first voltage divider resistor of the voltage divider circuit, and the drain of the PMOS transistor is connected to one end of the second voltage divider circuit of the voltage divider circuit; When the sampling circuit is working, the voltage at the other end of the first voltage divider resistor is higher than the voltage at the other end of the second voltage divider resistor.
6. The sampling circuit according to claim 3, characterized in that, The MOS transistor is an NMOS transistor; wherein, the drain of the NMOS transistor is connected to one end of the first voltage divider resistor of the voltage divider circuit, and the source of the NMOS transistor is connected to one end of the second voltage divider circuit of the voltage divider circuit; When the sampling circuit is working, the voltage at the other end of the first voltage divider resistor is higher than the voltage at the other end of the second voltage divider resistor.
7. The sampling circuit according to any one of claims 3 to 6, characterized in that, The switching circuit further includes a discharge resistor; wherein one end of the discharge circuit is connected to the gate of the MOS transistor, and the other end of the discharge resistor is grounded.
8. The sampling circuit according to any one of claims 3 to 6, characterized in that, The switching circuit further includes a current-limiting resistor; wherein one end of the current-limiting resistor is connected to the gate of the MOS transistor, and the other end of the current-limiting resistor is connected to the driving power supply.
9. The sampling circuit according to any one of claims 3 to 6, characterized in that, The switching circuit further includes a diode; wherein the anode of the diode is connected to the driving power supply, and the cathode of the diode is connected to the gate of the MOS transistor.
10. The sampling circuit according to claim 9, characterized in that, The switching circuit further includes a current-limiting resistor; wherein one end of the current-limiting resistor is connected to the anode of the diode, and the other end of the current-limiting resistor is connected to the driving power supply.
11. A variable frequency drive, characterized in that, The bus voltage collected by the sampling circuit according to any one of claims 1 to 10 is used to power the frequency converter for driving the motor.
12. A garment processing device, characterized in that, include: The sampling circuit and motor according to any one of claims 1 to 10, and the frequency converter according to claim 11, wherein the frequency converter drives the motor under the power supply of the bus voltage to enable the clothing processing equipment to operate.