A filter circuit, method, electrical appliance controller and washing machine

Abstract

The application relates to a filter circuit, a method, an electrical equipment controller and a washing machine. The filter circuit comprises a current input end for receiving a power supply current; a first inductor coil module and a second inductor coil module for filtering the power supply current when the power supply current flows; a branch switching module arranged between the current input end and the first inductor coil module and the second inductor coil module, used for switching between the first inductor coil module and the second inductor coil module, so that the power supply current received by the current input end flows from the first inductor coil module or the second inductor coil module; and a controller configured to control the branch switching module to disconnect the first inductor coil module and turn on the second inductor coil module when an electrical parameter of the first inductor coil module does not meet a first working condition. The problem of temperature rise is overcome, and the EMC performance is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of filtering, in particular to a filtering circuit, method, electrical equipment controller and washing machine. BACKGROUND

[0002] EMC (Electro Magnetic Compatibility) is also known as electromagnetic compatibility, which refers to the ability of electronic devices to generate electromagnetic energy without interfering with other electronic devices or being interfered by electromagnetic energy of other electronic devices.

[0003] With the improvement of living standards, electrical equipment such as washing machines and dryers is increasingly widely used. Controlling EMC performance during use of electrical equipment helps to ensure normal use of electrical equipment and reduce interference with other electrical equipment. However, after electronic equipment such as a washing machine runs for a period of time, copper loss and magnetic core loss in the circuit will cause temperature rise of the magnetic core, thereby changing the impedance characteristics of the magnetic core and causing EMC performance to decrease. SUMMARY

[0004] The present application provides a filtering circuit, method, electrical equipment controller and washing machine to at least solve the technical problem of improving EMC performance.

[0005] According to a first aspect of an embodiment of the present application, a filtering circuit is provided, comprising:

[0006] a current input end configured to receive a supply current;

[0007] a first inductor coil module configured to filter the supply current when the supply current flows therethrough;

[0008] a second inductor coil module configured to filter the supply current when the supply current flows therethrough;

[0009] a branch switching module disposed between the current input end and the first inductor coil module and the second inductor coil module, configured to switch between the first inductor coil module and the second inductor coil module, so that the supply current received by the current input end flows through the first inductor coil module or the second inductor coil module;

[0010] a controller configured to control the branch switching module to disconnect the first inductor coil module and turn on the second inductor coil module when an electrical parameter of the first inductor coil module does not meet a first working condition.

[0011] a controller configured to control the branch switching module to disconnect the first inductor coil module and turn on the second inductor coil module when an electrical parameter of the first inductor coil module does not meet a first working condition.

[0012] Optionally, the first inductor coil module comprises a first choke;

[0013] The first current end and the second current end of the first choke are used for connecting with the switching contact of the branch switching module, and the third current end and the fourth current end of the first choke are grounded.

[0014] The second inductor coil module comprises a second choke;

[0015] The first current end and the second current end of the second choke are used for connecting with the switching contact of the branch switching module, and the third current end and the fourth current end of the second choke are grounded.

[0016] Optionally, the branch switching module comprises a first relay and a second relay; the static contact of the first relay is connected with the positive pole of the current input end, and the switching contact of the first relay is used for connecting with the first current end of the first choke or the first current end of the second choke; the static contact of the second relay is connected with the negative pole of the current input end, and the switching contact of the second relay is used for connecting with the second current end of the first choke or the second current end of the second choke.

[0017] Or, the branch switching module comprises a first mos tube and a second mos tube; the first mos tube is used for connecting the positive pole of the current input end with the first current end of the first choke or the first current end of the second choke; and the second mos tube is used for connecting the negative pole of the current input end with the second current end of the first choke or the second current end of the second choke.

[0018] Or, the branch switching module is an IGBT switch; the IGBT switch is used for connecting the current input end with the first choke or the second choke.

[0019] Optionally, the filter circuit further comprises a filter capacitor module;

[0020] The filter capacitor module comprises: an X capacitor connected in parallel with the branch switching module, and / or a Y capacitor connected with the first end of the current input end to ground, and / or a Y capacitor connected with the second end of the current input end to ground, and / or an X capacitor connected in series with the current output end of the first inductor coil module, and / or an X capacitor connected in series with the current output end of the second inductor coil module, and / or a Y capacitor connected with the current output end of the first inductor coil module to ground, and / or a Y capacitor connected with the current output end of the second inductor coil module to ground.

[0021] Optionally, the filter circuit further comprises a first sampling node located at the current input end of the first inductor coil module and the second inductor coil module.

[0022] a second sampling node, located at the current output end of the first inductor coil module and the second inductor coil module;

[0023] The controller is configured to obtain the electrical parameter of the first inductor coil module or the second inductor coil module by using the first sampling node and the second sampling node.

[0024] Optionally, the controller is configured to:

[0025] When the power supply current flows through one of the first inductor coil module and the second inductor coil module, obtain the voltage parameter and the current parameter between the first sampling node and the second sampling node;

[0026] Calculate an impedance parameter based on the voltage parameter and the current parameter;

[0027] When the impedance parameter is greater than or equal to a preset first impedance threshold, determine that the electrical parameter of the one of the first inductor coil module and the second inductor coil module meets the first working condition;

[0028] When the impedance parameter is less than the first impedance threshold, determine that the electrical parameter of the one of the first inductor coil module and the second inductor coil module does not meet the first working condition, and control the branch switching module to connect the other one of the first inductor coil module and the second inductor coil module while disconnecting the one of the first inductor coil module and the second inductor coil module;

[0029] The first working condition corresponding to the first inductor coil module and the second inductor coil is the same or different.

[0030] According to a second aspect of the embodiments of the present application, a filtering method is provided, which is applied to the filtering circuit of the first aspect, and the filtering method comprises:

[0031] When the power supply current flows through one of the first inductor coil module and the second inductor coil module, obtain the electrical parameter of the one of the first inductor coil module and the second inductor coil module;

[0032] When the electrical parameter of the one of the first inductor coil module and the second inductor coil module does not meet the first working condition, control the branch switching module to connect the other one of the first inductor coil module and the second inductor coil module while disconnecting the one of the first inductor coil module and the second inductor coil module;

[0033] The first working condition corresponding to the first inductor coil module and the second inductor coil is the same or different.

[0034] According to a third aspect of the embodiments of the present application, an electrical equipment controller is provided, which applies the filtering method of the second aspect.

[0035] According to a fourth aspect of the embodiments of the present application, a washing machine is provided, which is provided with the filter circuit of the first aspect or the controller of the third aspect. Before the switching of the on-off states of the first inductor coil module and the second inductor coil module is needed, the controller controls at least one power-consuming load of the washing machine to be turned off.

[0036] Optionally, before the switching of the on-off states of the first inductor coil module and the second inductor coil module is needed, the controller determines whether the rotating speed of each power-consuming load of the washing machine is greater than a preset rotating speed threshold value.

[0037] If yes, the controller controls the corresponding power-consuming load to be slowed down, and after the rotating speed of the corresponding power-consuming load reaches a preset stable threshold value, the on-off states of the first inductor coil module and the second inductor coil module are switched.

[0038] In the embodiments of the present application, even if the EMC performance of the first inductor coil module is attenuated due to the temperature rise, the second inductor coil module is switched to replace the first inductor coil module to work, so that the performance of the filter circuit is not easily reduced due to the temperature rise, and the EMC performance is improved. BRIEF DESCRIPTION OF DRAWINGS

[0039] Figure 1 is a filter circuit schematic diagram provided by the embodiments of the present application.

[0040] Figure 2 is a filter circuit circuit diagram provided by the embodiments of the present application.

[0041] Figure 3 is a flow chart of a filter method provided by the embodiments of the present application. DETAILED DESCRIPTION

[0042] In order to enable persons skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by persons skilled in the art without creative labor should be within the protection scope of the present application.

[0043] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0044] According to an embodiment of this application, a method embodiment for a filtering circuit is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0045] like Figure 1 As shown, the filter circuit includes:

[0046] The current input terminal is used to receive the supply current.

[0047] The first inductor module is used to filter the power supply current when the power supply current is flowing through it.

[0048] The second inductor module is used to filter the power supply current when the power supply current is flowing through it.

[0049] A branch switching module is disposed between the current input terminal and the first inductor module and the second inductor module, and is used to switch between the first inductor module and the second inductor module, so that the power supply current received at the current input terminal flows from the first inductor module or the second inductor module.

[0050] The controller is configured to: when the electrical parameters of the first inductor module do not meet the first operating conditions, control the branch switching module to disconnect the first inductor module and turn on the second inductor module.

[0051] Based on the above, the first and second inductor modules can only be used independently. When the first inductor module's electrical parameters fail to meet the first operating conditions due to overheating, the system switches to the second inductor module. Since no power supply current flows through the second inductor module before switching, its temperature and electrical parameters are normal, making the filter circuit less prone to performance degradation due to temperature increases, thus improving EMC performance.

[0052] Optionally, such as Figure 2 As shown, the first inductor module includes a first choke coil;

[0053] The first current terminal and the second current terminal of the first choke are used to connect to the switching contact of the branch switching module, and the third current terminal and the fourth current terminal of the first choke are grounded.

[0054] The second inductor module includes a second choke coil;

[0055] The first and second current terminals of the second choke are used to connect to the switching contacts of the branch switching module, and the third and fourth current terminals of the second choke are grounded.

[0056] The branch switching module has a stationary contact and a switching contact. The stationary contact of the branch switching module is a normally connected contact that is connected to the current input terminal and is used to flow the power supply current. The switching contact is used to switch between the first choke and the second choke, so that the power supply current flows into the first choke or the second choke.

[0057] As described above, using a choke coil to filter the power supply current and suppress interference signals helps improve the performance of the filtering circuit.

[0058] Optionally, the branch switching module includes a first relay and a second relay; the stationary contact of the first relay is connected to the positive terminal of the current input terminal, and the switching contact of the first relay is used to connect to the first current terminal of the first choke or the first current terminal of the second choke; the stationary contact of the second relay is connected to the negative terminal of the current input terminal, and the switching contact of the second relay is used to connect to the second current terminal of the first choke or the second current terminal of the second choke.

[0059] The first and second relays work together. When it is necessary to switch the first choke to the second choke, the first and second relays are controlled simultaneously so that the switching contact of the first relay is connected to the first current terminal of the second choke, and the switching contact of the second relay is connected to the second current terminal of the second choke. The reverse is also true. This will not be elaborated further.

[0060] In one embodiment, both the first relay and the second relay are single-pole double-throw relays.

[0061] Optionally, the branch switching module includes a first MOSFET and a second MOSFET; the first MOSFET is used to connect the positive terminal of the current input terminal to the first current terminal of the first choke or the first current terminal of the second choke; the second MOSFET is used to connect the negative terminal of the current input terminal to the second current terminal of the first choke or the second current terminal of the second choke.

[0062] MOSFETs are used as switching devices.

[0063] Optionally, the branch switching module is an IGBT switch; the IGBT switch is used to connect the current input terminal to the first choke or the second choke.

[0064] IGBT switching circuits are used as switching devices.

[0065] In one embodiment, the branch switching module can be selected from relays, MOSFETs, and IGBTs, using one type of device to switch between the first choke and the second choke. Alternatively, in another embodiment, all three types of devices can be combined; for example, the branch switching module may include a relay and a MOSFET. The aim is simply to enable switching between the first and second chokes. This embodiment does not specifically limit the switching devices used in the branch switching module.

[0066] Based on the above, the branch switching module can use a variety of switching devices, which helps to make the filter circuit applicable to more types of electrical equipment and improve EMC performance and lifespan.

[0067] Optionally, the filtering circuit further includes a filtering capacitor module;

[0068] The filter capacitor module includes: an X capacitor connected in parallel with the branch switching module, and / or a Y capacitor with its first terminal of the current input grounded, and / or a Y capacitor with its second terminal of the current input grounded, and / or an X capacitor connected in series with the current output terminal of the first inductor module, and / or an X capacitor connected in series with the current output terminal of the second inductor module, and / or a Y capacitor with the current output terminal of the first inductor module grounded, and / or a Y capacitor with the current output terminal of the second inductor module grounded.

[0069] Specifically, such as Figure 2As shown, the filter capacitor module includes a first capacitor X1, a second capacitor X2, a third capacitor Y1, a fourth capacitor Y2, a fifth capacitor Y3, and a sixth capacitor Y6. The first capacitor X1 is connected in parallel with the first choke L1 and the second choke L2, and its two ends are connected to the positive and negative terminals of the current input terminal, respectively. The two ends of the second capacitor X2 are connected to the third and fourth current terminals of the first choke L1, respectively. At the same time, when the power supply current flows through the second choke L2, the two ends of the second capacitor X2 are connected to the third and fourth current terminals of the second choke L2, respectively.

[0070] One end of the third capacitor Y1 is located between the positive terminal of the current input terminal and the stationary contact of the first relay K1, and the other end of the third capacitor Y1 is grounded; one end of the fourth capacitor Y2 is connected to the stationary contact of the second relay K1, and the other end is grounded; the fifth capacitor Y3 and the sixth capacitor Y4 are both connected in parallel with the second capacitor X2 and grounded.

[0071] Based on the above, the filter capacitor module helps to store energy, buffer power-on, and filter, thereby improving EMC performance.

[0072] Optionally, the filtering circuit further includes a first parameter acquisition node located at the current input terminals of the first inductor module and the second inductor module;

[0073] The second parameter acquisition node is located at the current output terminal of the first inductor module and the second inductor module;

[0074] The controller is configured to acquire electrical parameters of the first inductor module or the second inductor module using the first and second parameter acquisition nodes.

[0075] Among them, such as Figure 2 As shown, the first parameter acquisition node is point A, and the second parameter acquisition node is point B. When it is necessary to obtain the electrical parameters of the first or second choke coil, the controller can acquire the voltage signal and / or current signal between the first and second parameter acquisition nodes.

[0076] Based on the above, the filter circuit contains two parameter acquisition nodes. Regardless of whether the power supply current flows through the first inductor module or the second inductor module, the electrical parameters of the corresponding inductor module can be obtained through the two parameter acquisition nodes. This facilitates the convenient and quick acquisition of electrical parameters to determine whether it is necessary to switch between the first and second inductor modules.

[0077] Optionally, the controller is configured to:

[0078] When the power supply current flows through either the first inductor module or the second inductor module, the voltage parameters and current parameters between the first and second parameter acquisition nodes are obtained.

[0079] The impedance parameters are calculated based on the voltage and current parameters.

[0080] When the impedance parameter is greater than or equal to a preset first impedance threshold, it is determined that the electrical parameter of one of the two meets the first operating condition.

[0081] When the impedance parameter is less than the first impedance threshold, it is determined that the electrical parameter of one of the two does not meet the first working condition, and the branch switching module is controlled to connect the other of the two while disconnecting the other of the two.

[0082] The first operating conditions for the first inductor module and the second inductor module may be the same or different.

[0083] Specifically, when the power supply current flows through the first inductor module, the voltage parameters and current parameters between the first and second parameter acquisition nodes are obtained.

[0084] The impedance parameters are calculated based on the voltage and current parameters.

[0085] When the impedance parameter is greater than or equal to a preset first impedance threshold, it is determined that the electrical parameters of the first inductor module meet the first operating conditions.

[0086] When the impedance parameter is less than the first impedance threshold, it is determined that the electrical parameters of the first inductor module do not meet the first operating conditions. The branch switching module is then controlled to connect the current input terminal to the second inductor module and disconnect the current input terminal from the first inductor module.

[0087] Wherein, impedance parameter = voltage parameter / current parameter, that is, Z = U / I, where Z is the impedance parameter, U is the voltage parameter, and I is the current parameter.

[0088] In one embodiment, the first impedance threshold is the minimum impedance value of the first inductor module.

[0089] By using the above steps, the impedance parameters are used to determine the extent to which the first inductor module is affected by temperature, thereby determining whether it is necessary to switch the first inductor module to the second inductor module. This helps to improve the timeliness of the switching and thus ensure the EMC performance of the filter circuit.

[0090] When the power supply current flows through the second inductor module, the voltage parameters and current parameters between the first and second parameter acquisition nodes are obtained.

[0091] The impedance parameters are calculated based on the voltage and current parameters.

[0092] When the impedance parameter is greater than or equal to a preset second impedance threshold, it is determined that the electrical parameters of the second inductor module meet the second operating conditions.

[0093] When the impedance parameter is less than the second impedance threshold, it is determined that the electrical parameters of the second inductor module do not meet the second operating conditions. The branch switching module is then controlled to connect the current input terminal to the first inductor module and simultaneously disconnect the current input terminal from the second inductor module.

[0094] The method for calculating the impedance parameters of the second inductor module is the same as that for the first inductor module, and will not be repeated here. The second impedance threshold is the minimum impedance value of the second inductor module. Specifically, the minimum impedance values ​​of the first and second inductor modules can be obtained through a temperature rise test; this embodiment does not impose specific limitations on this.

[0095] After the performance of the first inductor module deteriorates due to temperature rise, it switches to the second inductor module. Similarly, after the performance of the second inductor module deteriorates due to temperature rise, it switches back to the first inductor module.

[0096] Through the above, the first inductor module and the second inductor module are used alternately. The filter circuit can be used for a long time, and the performance is always maintained at a relatively high level. It is not easily affected by temperature rise, thus improving EMC performance.

[0097] This application embodiment also provides a filtering method applied to the filtering circuit described above, the filtering method comprising:

[0098] When a supply current flows through either the first inductor module or the second inductor module, the electrical parameters of the one of them are obtained.

[0099] When the electrical parameters of one of the two do not meet the first operating condition, the control branch switching module connects the other of the two while disconnecting the first of the two.

[0100] The first operating conditions for the first inductor module and the second inductor module may be the same or different.

[0101] Optionally, obtaining the electrical parameters of the first inductor module includes:

[0102] The electrical parameters of the first inductor module or the second inductor module are obtained using the first and second parameter acquisition nodes.

[0103] Optionally, when the power supply current flows through the first inductor module, the voltage parameters and current parameters between the first and second parameter acquisition nodes are obtained.

[0104] The impedance parameters are calculated based on the voltage and current parameters.

[0105] When the impedance parameter is greater than or equal to a preset first impedance threshold, it is determined that the electrical parameters of the first inductor module meet the first operating conditions.

[0106] When the impedance parameter is less than the first impedance threshold, it is determined that the electrical parameters of the first inductor module do not meet the first operating conditions. The branch switching module is then controlled to connect the current input terminal to the second inductor module and disconnect the current input terminal from the first inductor module.

[0107] Optionally, when the power supply current flows through the second inductor module, the voltage parameters and current parameters between the first and second parameter acquisition nodes are obtained.

[0108] The impedance parameters are calculated based on the voltage and current parameters.

[0109] When the impedance parameter is greater than or equal to a preset second impedance threshold, it is determined that the electrical parameters of the second inductor module meet the second operating conditions.

[0110] When the impedance parameter is less than the second impedance threshold, it is determined that the electrical parameters of the second inductor module do not meet the second operating conditions. The branch switching module is then controlled to connect the current input terminal to the first inductor module and simultaneously disconnect the current input terminal from the second inductor module.

[0111] Optionally, such as Figure 3 As shown, before controlling the branch switching module to disconnect the first inductor module and turn on the second inductor module, the method further includes:

[0112] Determine whether the motor in the electrical equipment to which the filter circuit belongs is running at high speed;

[0113] If so, reduce the motor speed, and after the speed reduction is completed, shut off all loads of the electrical equipment, and then jump to the step control where the branch switching module disconnects the first inductor coil module and turns on the second inductor coil module.

[0114] If not, then all loads of the electrical equipment are turned off, and then the process jumps to the step control whereby the branch switching module disconnects the first inductor module and turns on the second inductor module.

[0115] Specifically, when the motor speed exceeds a preset speed threshold, the motor is determined to be operating at high speed. When the motor speed falls below a preset stability threshold, the motor speed reduction is determined to be complete. In one embodiment, the speed threshold is greater than the stability threshold; in another embodiment, the speed threshold and the stability threshold are equal.

[0116] The load on the electrical equipment can be a fan, heater, etc., and this embodiment does not specifically limit it.

[0117] Through the above, the voltage and current parameters between the first and second parameter acquisition nodes are monitored in real time, and the impedance parameters are calculated based on the voltage and current parameters. Once the impedance parameter exceeds the impedance threshold, the first and second inductor modules are switched, so that the EMC performance is not easily affected by the temperature rise, thereby improving the EMC performance.

[0118] This application also provides an electrical equipment controller that applies the filtering method described above.

[0119] This application embodiment also provides a washing machine equipped with the above-described filtering circuit or controller. Before switching the conduction state of the first inductor coil module and the second inductor coil module, the controller controls at least one power-consuming load of the washing machine to be turned off.

[0120] Optionally, before switching the conduction state of the first inductor module and the second inductor module, the controller determines whether the rotation speed of each power-consuming load of the washing machine is greater than a preset rotation speed threshold.

[0121] If so, the controller controls the corresponding power-consuming load to slow down, and after the speed of the corresponding power-consuming load reaches a preset stable threshold, switches the conduction state of the first inductor coil module and the second inductor coil module.

[0122] The embodiments of this application have at least the following technical effects:

[0123] 1. It solves the problem of EMC performance degradation caused by temperature rise;

[0124] 2. A more flexible filtering circuit is provided to ensure the optimal operating condition of electrical equipment;

[0125] 3. After the filtering circuit, there is a rectifier circuit and transformer current. A bus capacitor exists after the rectifier circuit. Even if the program temporarily cuts off the AC power supply to the washing machine controller, the energy stored in the bus capacitor can still ensure that the controller's main chip continues to work for a short time. The relay switching process can be completed within tens of milliseconds, and the switching process will not affect the program's operation.

[0126] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0127] In the above embodiments of this application, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0128] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interfaces; the indirect coupling or communication connection between units or modules may be electrical or other forms.

[0129] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0130] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0131] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0132] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A filter circuit, characterized in that, include: The current input terminal is used to receive the supply current. The first inductor module is used to filter the power supply current when the power supply current is flowing through it. The second inductor module is used to filter the power supply current when the power supply current is flowing through it. A branch switching module is disposed between the current input terminal and the first inductor module and the second inductor module, and is used to switch between the first inductor module and the second inductor module, so that the power supply current received at the current input terminal flows from the first inductor module or the second inductor module. The controller is configured to: when the electrical parameters of the first inductor module do not meet the first operating conditions, control the branch switching module to disconnect the first inductor module and turn on the second inductor module. in: The filtering circuit also includes: The first parameter acquisition node is located at the current input terminal of the first inductor module and the second inductor module; The second parameter acquisition node is located at the current output terminal of the first inductor module and the second inductor module; The controller is configured to acquire electrical parameters of the first inductor module or the second inductor module using the first and second parameter acquisition nodes. The controller is configured to: When the power supply current flows through either the first inductor module or the second inductor module, the voltage parameters and current parameters between the first and second parameter acquisition nodes are obtained. The impedance parameters are calculated based on the voltage and current parameters. When the impedance parameter is greater than or equal to a preset first impedance threshold, it is determined that the electrical parameter of one of the two meets the first operating condition. When the impedance parameter is less than the first impedance threshold, it is determined that the electrical parameter of one of the two does not meet the first working condition, and the branch switching module is controlled to connect the other of the two while disconnecting the other of the two. The first operating conditions for the first inductor module and the second inductor module may be the same or different.

2. The filter circuit according to claim 1, characterized in that, The first inductor module includes a first choke coil; The first current terminal and the second current terminal of the first choke are used to connect to the switching contact of the branch switching module, and the third current terminal and the fourth current terminal of the first choke are grounded. The second inductor module includes a second choke coil; The first and second current terminals of the second choke are used to connect to the switching contacts of the branch switching module, and the third and fourth current terminals of the second choke are grounded.

3. The filter circuit according to claim 2, characterized in that, The branch switching module includes a first relay and a second relay; the stationary contact of the first relay is connected to the positive terminal of the current input terminal, and the switching contact of the first relay is used to connect to the first current terminal of the first choke or the first current terminal of the second choke; the stationary contact of the second relay is connected to the negative terminal of the current input terminal, and the switching contact of the second relay is used to connect to the second current terminal of the first choke or the second current terminal of the second choke. Alternatively, the branch switching module includes a first MOSFET and a second MOSFET; the first MOSFET is used to connect the positive terminal of the current input terminal to the first current terminal of the first choke or the first current terminal of the second choke; the second MOSFET is used to connect the negative terminal of the current input terminal to the second current terminal of the first choke or the second current terminal of the second choke. Alternatively, the branch switching module may be an IGBT switch; the IGBT switch is used to connect the current input terminal to the first choke or the second choke.

4. The filter circuit according to any one of claims 1-3, characterized in that, The filtering circuit also includes a filter capacitor module; The filter capacitor module includes: an X capacitor connected in parallel with the branch switching module, and / or a Y capacitor with its first terminal of the current input grounded, and / or a Y capacitor with its second terminal of the current input grounded, and / or an X capacitor connected in series with the current output terminal of the first inductor module, and / or an X capacitor connected in series with the current output terminal of the second inductor module, and / or a Y capacitor with the current output terminal of the first inductor module grounded, and / or a Y capacitor with the current output terminal of the second inductor module grounded.

5. A filtering method, characterized in that, The filtering method, applied to the filtering circuit according to any one of claims 1-4, comprises: When a supply current flows through either the first inductor module or the second inductor module, the electrical parameters of the one of them are obtained. When the electrical parameters of one of the two do not meet the first operating condition, the control branch switching module connects the other of the two while disconnecting the first of the two. The first operating conditions for the first inductor module and the second inductor module may be the same or different.

6. An electrical equipment controller, characterized in that, The filtering method described in claim 5 is applied.

7. A washing machine, characterized in that, The washing machine is equipped with a filter circuit as described in any one of claims 1-4 or an electrical equipment controller as described in claim 6. Before switching the conduction state of the first inductor module and the second inductor module is required, the controller controls at least one power-consuming load of the washing machine to shut down.

8. The washing machine according to claim 7, characterized in that, Before switching the conduction state of the first inductor coil module and the second inductor coil module, the controller determines whether the rotation speed of each power-consuming load of the washing machine is greater than a preset rotation speed threshold. If so, the controller controls the corresponding power-consuming load to slow down, and after the speed of the corresponding power-consuming load reaches a preset stable threshold, switches the conduction state of the first inductor coil module and the second inductor coil module.

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