CN220527922U

CN220527922U - Protection circuit and motor device

Info

Publication number: CN220527922U
Application number: CN202322184662.6U
Authority: CN
Inventors: 杨建德; 方强; 钟立
Original assignee: Huaian Welling Motor Manufacturing Co Ltd
Current assignee: Huaian Welling Motor Manufacturing Co Ltd
Priority date: 2023-08-14
Filing date: 2023-08-14
Publication date: 2024-02-23
Anticipated expiration: 2033-08-14

Abstract

The embodiment of the application provides a protection circuit and a motor device. The protection circuit is used for a motor device, the motor device comprises a motor control chip, the motor control chip is connected with a bus end, the bus end is used for supplying power to the motor control chip, the protection circuit comprises a first surge absorption module, a second surge absorption module and a resonance module, one end of the first surge absorption module is connected with a bus end, the other end of the first surge absorption module is connected with a grounding end, and the protection circuit is used for absorbing a surge voltage signal of a first frequency band of the bus end; one end of the second surge absorbing module is connected with the bus terminal, the other end of the second surge absorbing module is connected with the grounding terminal and is used for absorbing surge voltage signals of a second frequency band of the bus terminal, the first frequency band is smaller than the second frequency band, one end of the resonance module is connected with the bus terminal, and the other end of the resonance module is connected with the grounding terminal and is used for absorbing impact current and impact voltage of the bus terminal. Therefore, the protection capability of the motor control chip can be effectively improved, and the motor control chip is prevented from being turned around by an air conditioner fan due to the failure of surge signal impact.

Description

Protection circuit and motor device

Technical Field

The application relates to the technical field of air conditioners, in particular to a protection circuit and a motor device.

Background

At present, in an air conditioner brushless direct current motor, a motor control chip can be installed inside the motor, driving voltage of the motor is provided through an air conditioner whole machine, the motor is connected with the air conditioner whole machine through opposite-plug terminals, if terminal contact looseness or power supply voltage fluctuation occurs, surge impact signals can be generated, and over-current impact is generated on a driving circuit of the motor with the built-in motor control chip, so that over-current failure of motor driving and peripheral circuits of the motor is easy to cause.

Disclosure of Invention

The application provides a protection circuit and a motor device.

The protection circuit of this application embodiment for motor device, motor device includes motor control chip, motor control chip is connected with the generating line end, the generating line end is used for motor control chip power supply, protection circuit includes:

one end of the first surge absorbing module is connected with the bus end, and the other end of the first surge absorbing module is connected with the grounding end and is used for absorbing a surge voltage signal of a first frequency band of the bus end;

one end of the second surge absorbing module is connected with the bus end, the other end of the second surge absorbing module is connected with the grounding end and is used for absorbing surge voltage signals of a second frequency band of the bus end, and the first frequency band is smaller than the second frequency band;

and one end of the resonance module is connected with the bus end, and the other end of the resonance module is connected with the grounding end and is used for absorbing impact current and impact voltage of the bus end.

In some embodiments, the first surge absorption module includes a thin film capacitor.

In certain embodiments, the capacitance of the thin film capacitor is greater than or equal to 0.2 microfarads.

In some embodiments, the second surge absorption module includes a high voltage tile capacitor.

In some embodiments, the capacitance of the high voltage chip capacitor is greater than or equal to 10 nanofarads.

In certain embodiments, the resonance module includes:

the first end of the filter capacitor is connected with the bus end;

and one end of the first resistor is connected with the second end of the filter capacitor, and the other end of the first resistor is connected with the grounding end.

And one end of the second resistor is connected with the second end of the filter capacitor, and the other end of the second resistor is connected with the grounding end.

In some embodiments, the first resistor and the second resistor have equal resistance values, and the capacitance value of the filter capacitor is greater than or equal to 10 nanofarads.

In certain embodiments, the guard circuit further comprises:

and one end of the third resistor is connected with the bus end, and the other end of the third resistor is connected with the first surge absorption module, the second surge absorption module and the resonance module.

The motor device comprises an outdoor unit, a plurality of indoor units and a protection circuit, wherein the indoor units are connected with the outdoor unit, and the protection circuit is connected with the indoor units.

The motor device provided by the embodiment of the application comprises the protection circuit.

In some embodiments, the motor device further comprises a motor control chip, a bus end and a motor, wherein the motor control chip is respectively connected with the bus end and the motor, the bus end is used for supplying power to the motor control chip, and the motor control chip is used for driving the motor.

In the protection circuit and the motor device of the embodiment of the application, the first surge absorption module absorbs the surge voltage signal of the first frequency band of the bus terminal, the second surge absorption module absorbs the surge voltage signal of the second frequency band of the bus terminal, and the resonance module filters out the surge impact current and the surge voltage of the bus terminal, so that the surge signal of the bus terminal is prevented from impacting the motor control chip to cause the motor control chip to fail in an over-current manner, and the safety of the motor device is ensured.

Additional aspects and advantages of the application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the application.

Drawings

The foregoing and/or additional aspects and advantages of the present application will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a block diagram of a protection circuit according to an embodiment of the present application;

FIG. 2 is a schematic circuit diagram of a motor apparatus of an embodiment of the present application;

fig. 3 is a graph of test results of the guard according to an embodiment of the present application.

Description of main reference numerals:

the protection circuit 10, the first surge absorption module 11, the thin film capacitor C1, the second surge absorption module 12, the high-voltage ceramic chip capacitor C2, the resonance module 13, the filter capacitor C3, the first resistor R1, the second resistor R2 and the third resistor R3;

motor device 100, bus terminal VM, ground terminal GND, motor control chip 20, and motor 30.

Detailed Description

Embodiments of the present application are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary only for the purpose of explaining the present application and are not to be construed as limiting the present application.

In the description of the present application, it should be understood that the terms "center," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," etc. indicate or are based on the orientation or positional relationship shown in the drawings, merely for convenience of description and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present application. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more of the described features. In the description of the present application, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.

In the description of the present application, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically connected, electrically connected or can be communicated with each other; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art as the case may be.

In this application, unless expressly stated or limited otherwise, a first feature "above" or "below" a second feature may include both the first and second features being in direct contact, and may also include the first and second features not being in direct contact but being in contact with each other by way of additional features therebetween. Moreover, a first feature being "above," "over" and "on" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature is higher in level than the second feature. The first feature being "under", "below" and "beneath" the second feature includes the first feature being directly under and obliquely below the second feature, or simply means that the first feature is less level than the second feature.

The following disclosure provides many different embodiments or examples for implementing different structures of the present application. In order to simplify the disclosure of the present application, the components and arrangements of specific examples are described below. Of course, they are merely examples and are not intended to limit the present application. Furthermore, the present application may repeat reference numerals and/or letters in the various examples, which are for the purpose of brevity and clarity, and which do not in themselves indicate the relationship between the various embodiments and/or arrangements discussed. In addition, the present application provides examples of various specific processes and materials, but one of ordinary skill in the art may recognize the application of other processes and/or the use of other materials.

In the existing brushless direct current motor control technology, high-voltage IGBT or MOS, driving IC and control PWM signals can be integrated into one chip, and bus voltage, 15V control and speed regulation control signals are provided by the whole air conditioner to realize the control scheme of motor operation.

Because of the upgrading of energy efficiency, the scheme of the built-in control board of the direct current motor is used more and more, and the built-in control board of the direct current motor means that the motor control board is arranged inside the motor, and motor driving voltage is provided through the whole air conditioner. Because the built-in control board of the motor is connected with the whole air conditioner through the opposite plug connector, the loosening of the terminal can cause ignition, and the surge signal impact is easily formed on the direct current bus due to the fluctuation of the power grid voltage in part of areas, so that the motor control board is in over-power failure.

In view of this, referring to fig. 1, the embodiment of the present application provides a protection circuit 10, where the protection circuit 10 is used for a motor device 100, the motor device 100 includes a motor control chip 20, the motor control chip 20 is connected to a bus terminal VM, the bus terminal VM is used for supplying power to the motor control chip 20, and the protection circuit 10 includes a first surge absorption module 11, a second surge absorption module 12 and a resonance module 13.

One end of the first surge absorbing module 11 is connected to the bus terminal VM, and the other end of the first surge absorbing module 11 is connected to the ground GND, for absorbing a surge voltage signal of the first frequency band of the bus terminal VM. One end of the second surge absorbing module 12 is connected with the bus terminal VM, the other end of the second surge absorbing module 12 is connected with the ground terminal GND for absorbing a surge voltage signal of a second frequency band of the bus terminal VM, and the first frequency band is smaller than the second frequency band, one end of the resonance module 13 is connected with the bus terminal VM, and the other end of the resonance module 13 is connected with the ground terminal GND for absorbing an impact current and an impact voltage of the bus terminal VM.

Referring to fig. 2, the present application further provides a motor apparatus 100, where the motor apparatus 100 includes the protection circuit 10 described above.

In the protection circuit 10 of this embodiment, the first surge absorption module 11 absorbs the surge voltage signal of the first frequency band of the bus terminal VM, the second surge absorption module 12 absorbs the surge voltage signal of the second frequency band of the bus terminal VM, and the resonance module 13 filters out the surge impact current and the surge voltage of the bus terminal VM, so that the surge signal of the bus terminal VM is prevented from impacting the motor control chip 20 to cause the motor control chip 20 to fail in an over-current manner, and thus, the protection circuit 10 can effectively play a protection role on the motor control chip 20, and the reliability of the motor device 100 is improved.

Specifically, the motor device 100 may be a brushless dc motor of an air conditioner, that is, the protection circuit 10 may be used for the brushless dc motor of the air conditioner, the motor device 100 and the whole air conditioner are connected through opposite terminals, and the motor control chip 20 is installed inside the motor control board, and the motor control chip 20 is used for driving the motor to work. The protection circuit 10 may be installed in the motor apparatus 100.

Referring to fig. 2, the motor device 100 may include a bus end VM, a motor control chip 20 and a motor 30, where the bus end VM may be electrically connected to the air conditioner through a wire insertion terminal, the bus end VM is further connected to the motor control chip 20, for providing voltage to the motor control chip 20, the motor control chip 20 is connected to the motor 30, and the motor control chip 20 may be integrated with modules such as an IGBT module, a driving module, and a PWM signal processing module, for driving the motor 30 to make the air conditioner fan work.

The protection circuit 10 may be located inside the motor device 100 and connected to the bus terminal VM and the ground terminal GND for eliminating surge impact on the bus terminal VM. As can be appreciated, the surge impacts transient waves of current, voltage or power transmitted along the line, the surge impacts the failure of the motor control board easily, so that the surge impacts in the bus terminal VM are eliminated through the protection circuit 10, and the surge impacts are prevented from flowing into the motor control board, so that the safety of the motor control board is ensured, and the motor device 100 can work normally.

Further, the protection circuit 10 may include a first surge absorbing module 11, a second surge absorbing module 12 and a resonance module 13. The first surge absorbing module 11 is electrically connected to the busbar terminal VM and the ground terminal GND, the second surge absorbing module 12 is electrically connected to the busbar terminal VM and the ground terminal GND, and the resonance module 13 is electrically connected to the busbar terminal VM and the ground terminal GND.

The first surge absorbing module 11 is configured to filter a surge voltage signal of a first frequency band in the bus-bar terminal VM, the second surge absorbing module 12 is configured to filter a surge voltage signal of a second frequency band in the bus-bar terminal VM, and the first frequency band is smaller than the second frequency band, for example, the first frequency band may be a low-voltage frequency band, and the second frequency band may be a high-voltage frequency band, that is, the first surge absorbing module 11 is configured to absorb a low-frequency surge voltage signal in the bus-bar terminal VM, and the second surge absorbing module 12 is configured to absorb a high-frequency surge voltage signal in the bus-bar terminal VM. The resonance module 13 is used to absorb the rush current and the surge voltage of the bus-bar terminal VM.

In some embodiments, the first surge absorbing module 11 includes a thin film capacitor C1. As will be understood by those skilled in the art, the film capacitor C1 is a capacitor having a cylindrical structure in which a metal foil is used as an electrode and is laminated with a plastic film such as polyethylene, polypropylene, polystyrene or polycarbonate from both ends and then wound. The thin film capacitor C1 has the advantages of no polarity, high insulation resistance, excellent frequency characteristic (wide frequency response), small dielectric loss, long service life and the like, so that the low-frequency surge voltage signal on the bus terminal VM can be reduced by using the thin film capacitor C1 as the surge voltage signal for absorbing the low frequency band.

In this embodiment, the capacitance value of the thin film capacitor C1 is 0.2 microfarads or more. As can be appreciated, if the capacitance of the thin film capacitor C1 is too small, the bearing capacity of the thin film capacitor C1 is limited and is easy to be damaged, which may cause that the low frequency surge voltage signal cannot be absorbed later, so that the bearing capacity of the thin film capacitor C1 can be ensured by setting the capacitance of the thin film capacitor C1 to be greater than or equal to 10 microfarads in the embodiment. For example, the capacitance value of the thin film capacitor C1 may be 0.2 microfarads, 0.22 microfarads, 0.24 microfarads, 0.3 microfarads, 0.4 microfarads or more, and the specific size of the thin film capacitor C1 is not limited, and may be selected according to practical situations, for example, in the present embodiment, the thin film capacitor C1 may be 0.22 microfarads.

In some embodiments, the second surge absorption module 12 includes a high voltage tile capacitor C2.

The high-voltage ceramic chip capacitor C2 is a capacitor using a ceramic material as a medium, the high-voltage ceramic chip capacitor C2 can resist abrasion and direct current high voltage, and the capacity loss changes along with the temperature frequency, has high stability, can eliminate high-frequency interference, and is reliable in long-term operation.

In this way, the second surge absorbing module 12 can ensure to absorb the high-frequency surge voltage signal of the bus terminal VM by providing the high-voltage ceramic chip capacitor C2.

In some embodiments, the capacitance of the high voltage chip capacitor C2 is 10 nanofarads or more. If the capacitance of the high-voltage ceramic chip capacitor C2 is too small, the high-voltage ceramic chip capacitor C2 has limited bearing capacity and is easy to damage, and may not absorb the high-frequency surge voltage signal later, so in this embodiment, the capacitance of the high-voltage ceramic chip capacitor C2 is set to be equal to or greater than 10 nano-meters, and the bearing capacity of the high-voltage ceramic chip capacitor C2 can be ensured, for example, in this embodiment, the capacitance of the high-voltage ceramic chip capacitor C2 can be equal to 10 nano-meters.

In some embodiments, the resonance module 13 may be an RC resonance circuit, and in particular, the resonance module 13 may include a filter capacitor C3, a first resistor R1, and a second resistor R2. The filter capacitor C3 comprises a first end and a second end, the first end of the filter resistor is connected with the bus terminal VM, and the second end of the filter resistor is connected with the first resistor R1 and the second resistor R2.

One end of the first resistor R1 is connected with the second end of the filter capacitor C3, and the other end of the first resistor R1 is connected with the grounding end GND.

One end of the second resistor R2 is connected with the second end of the filter capacitor C3, and the other end of the second resistor R2 is connected with the ground end GND.

In some embodiments, the filter capacitor C3 may be a high-voltage ceramic capacitor, and the capacitance of the filter capacitor C3 is greater than or equal to 10 nano-farads. For example, in some examples, the capacitance of the filter capacitor C3 may be 10 nanofarads. The first resistor R1 and the second resistor R2 have the same resistance value, and are both 22 ohms.

In some embodiments, the protection circuit 10 further includes a third resistor R3, where one end of the third resistor R3 is connected to the bus terminal VM, and the other end is connected to the first surge absorption module 11, the second surge absorption module 12, and the resonance module 13.

Referring to fig. 3, fig. 3 is a waveform test chart of the motor control chip 20 at the moment of switching on/off the bus end VM in the operation state of the motor device 100, and it can be determined in the test that the protection circuit 10 can effectively ensure the safety of the motor control chip 20.

In some embodiments, the motor apparatus 100 may further include a hall detection module, a current limiting module, and a temperature protection module, wherein the hall detection module is used for detecting a rotation speed of the motor, the current limiting module is used for controlling a current of the motor, and the temperature protection module is used for detecting a temperature of the motor.

In the description of the present specification, reference to the terms "one embodiment," "certain embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present application. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the present application have been shown and described, it will be understood by those of ordinary skill in the art that: many changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the application, the scope of which is defined by the claims and their equivalents.

Claims

1. A protection circuit for a motor device, characterized in that, the motor device includes motor control chip, motor control chip is connected with the busbar end, the busbar end is used for motor control chip power supply, protection circuit includes:

2. The protection circuit of claim 1, wherein the first surge absorption module comprises a thin film capacitor.

3. The protection circuit of claim 2, wherein the capacitance of the thin film capacitor is greater than or equal to 0.2 microfarads.

4. The protection circuit of claim 3, wherein the second surge absorption module comprises a high voltage tile capacitor.

5. The protection circuit of claim 4, wherein the capacitance of the high voltage tile capacitor is greater than or equal to 10 nanofarads.

6. The protection circuit of claim 1, wherein the resonant module comprises:

the first end of the filter capacitor is connected with the bus end;

one end of the first resistor is connected with the second end of the filter capacitor, and the other end of the first resistor is connected with the grounding end;

7. The protection circuit of claim 6, wherein the first resistor and the second resistor have equal resistance values, and the capacitance value of the filter capacitor is greater than or equal to 10 nanofarads.

8. The protection circuit of claim 1, further comprising:

9. An electrical machine arrangement comprising a protection circuit as claimed in any one of claims 1 to 8.

10. The motor apparatus of claim 9 further comprising a motor control chip, a bus terminal and a motor, the motor control chip being connected to the bus terminal and the motor, respectively, the bus terminal being configured to power the motor control chip, the motor control chip being configured to drive the motor.