Over-temperature protection circuit, circuit board and air conditioner system of air conditioner system

Abstract

The application provides an over-temperature protection circuit of an air conditioner system, a circuit board and the air conditioner system. The air conditioner system comprises an open-winding motor, a first IPM module and a second IPM module. The over-temperature protection circuit comprises a voltage comparison module, a switching module and an MCU module. The first IPM module outputs a first temperature signal to an input end of the voltage comparison module. The second IPM module outputs a second temperature signal to the input end of the voltage comparison module. The voltage comparison module is used for comparing the first temperature signal and the second temperature signal and outputting a level control signal. The switching module is used for determining a signal output state according to the level control signal. The signal output state comprises outputting the first temperature signal or outputting the second temperature signal. The MCU module is used for controlling a working state of the first IPM module according to the first temperature signal or controlling a working state of the second IPM module according to the second temperature signal. The effect of simultaneously monitoring the working states of the first IPM module and the second IPM module can be achieved, and the hardware circuit design cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of air conditioner technology, and in particular to an over-temperature protection circuit, circuit board, and air conditioner system for an air conditioner system. Background Technology

[0002] Open-winding motors are widely used in various household appliances, such as air conditioning systems. Typically, intelligent power modules (IPMs) are placed on both sides of the open-winding motor for coordinated control. The IPM module integrates power switching devices and drive circuits. During operation, the IPM module is prone to overheating due to factors such as rapid switching of the switching devices or excessive power, which may damage the switching devices and affect the normal operation of the drive circuit, thus reducing the working stability of the open-winding motor. Therefore, related technologies usually include a corresponding over-temperature protection circuit in each IPM module to monitor its operating status. This requires separate monitoring of the operating status of different IPM modules and occupies multiple control chip ports, increasing the cost of hardware circuit design. Summary of the Invention

[0003] This invention aims to at least solve one of the technical problems existing in the prior art. To this end, this invention proposes an over-temperature protection circuit, circuit board, and air conditioning system for an air conditioner system, which can simultaneously monitor the operating status of the first IPM module and the second IPM module, thereby reducing the hardware circuit design cost.

[0004] In a first aspect, embodiments of the present invention provide an over-temperature protection circuit for an air conditioning system. The air conditioning system includes an open-winding motor, a first IPM module and a second IPM module disposed on both sides of the open-winding motor. The over-temperature protection circuit includes a voltage comparison module, a switching module, and an MCU module. The first IPM module outputs a first temperature signal to the input terminal of the voltage comparison module, and the second IPM module outputs a second temperature signal to the input terminal of the voltage comparison module. The voltage comparison module is used to compare the first temperature signal and the second temperature signal and output a level control signal. The switching module is connected to the voltage comparison module, the first IPM module, and the second IPM module respectively. The switching module is used to determine a signal output state according to the level control signal. The signal output state includes outputting the first temperature signal or outputting the second temperature signal. The MCU module is connected to the switching module, the first IPM module, and the second IPM module respectively. The MCU module is used to control the operating state of the first IPM module according to the first temperature signal or to control the operating state of the second IPM module according to the second temperature signal.

[0005] The over-temperature protection circuit of the air conditioner system provided by the embodiments of the present invention has at least the following beneficial effects: the first IPM module outputs a first temperature signal to the input terminal of the voltage comparison module, and the second IPM module outputs a second temperature signal to the input terminal of the voltage comparison module. The voltage comparison module compares the received first temperature signal and second temperature signal and outputs a level control signal to the switch module. The switch module is connected to the first IPM module and the second IPM module respectively, and can determine the signal output state according to the level control signal. That is, the switch module can output the first temperature signal to the MCU module according to the level control signal, or output the second temperature signal to the MCU module according to the level control signal. The MCU module can control the working state of the first IPM module according to the first temperature signal, or control the working state of the second IPM module according to the second temperature signal, thereby achieving the effect of simultaneously monitoring the working state of the first IPM module and the second IPM module, reducing the hardware circuit design cost.

[0006] In the over-temperature protection circuit of the above-mentioned air conditioning system, the switching module includes a first terminal connected to the output terminal of the first IPM module, a second terminal connected to the output terminal of the second IPM module, a third terminal connected as an output terminal to the MCU module, and a control terminal connected to the output terminal of the voltage comparison module; the level control signal includes a first level signal and a second level signal; when the control terminal receives the first level signal, the switching module connects the first terminal and the third terminal; when the control terminal receives the second level signal, the switching module connects the second terminal and the third terminal.

[0007] When the control terminal receives a first-level signal from the voltage comparison module, the switch module turns on the first and third terminals, thereby inputting the first temperature signal output by the first IPM module to the MCU module. When the control terminal receives a second-level signal from the voltage comparison module, the switch module turns on the second and third terminals, thereby inputting the second temperature signal output by the second IPM module to the MCU module.

[0008] In the over-temperature protection circuit of the above-mentioned air conditioning system, the voltage comparison module includes a comparator. One input terminal of the comparator is connected to the first IPM module to obtain the first temperature signal, and the other input terminal of the comparator is connected to the second IPM module to obtain the second temperature signal. The output terminal of the comparator is connected to the control terminal and is used to output the first level signal when the first temperature signal is greater than the second temperature signal and to output the second level signal when the second temperature signal is greater than the first temperature signal.

[0009] By setting a comparator in the voltage comparison module and connecting its two input terminals to the first IPM module and the second IPM module respectively, a first temperature signal and a second temperature signal can be acquired. The comparator compares the first temperature signal and the second temperature signal and outputs a level control signal to the control terminal of the switch module. When the first temperature signal is greater than the second temperature signal, the comparator outputs a first level signal. After receiving the first level signal, the control terminal of the switch module conducts the first terminal and the third terminal, thereby inputting the first temperature signal to the MCU module. When the second temperature signal is greater than the first temperature signal, the comparator outputs a second level signal. After receiving the second level signal, the control terminal of the switch module conducts the second terminal and the third terminal, thereby inputting the second temperature signal to the MCU module.

[0010] In the over-temperature protection circuit of the above-mentioned air conditioning system, the switching module further includes a first switch connected in series between the first terminal and the output terminal of the first IPM module, and a second switch connected in series between the second terminal and the output terminal of the second IPM module.

[0011] It should be noted that the first switch is connected in series between the first terminal and the output terminal of the first IPM module. When the first switch is closed and the control terminal receives the first level signal, the first temperature signal can be turned on to flow to the first channel of the MCU module. The first temperature signal is output from the output terminal of the first IPM module, flows through the first switch, the first terminal, and the third terminal in sequence, and is finally input into the MCU module. Similarly, when the second switch is closed and the control terminal receives the second level signal, the second temperature signal can be turned on to flow to the second channel of the MCU module. The second temperature signal is output from the output terminal of the second IPM module, flows through the second switch, the second terminal, and the third terminal in sequence, and is finally input into the MCU module.

[0012] In the over-temperature protection circuit of the above-mentioned air conditioning system, the switching module further includes an enable terminal; when the enable terminal receives a first enable signal, it controls the first switch and the second switch to close; when the enable terminal receives a second enable signal, it controls the first switch and the second switch to open.

[0013] It should be noted that the switch module also has an enable terminal, which determines the connection state of the switch module's input and output. When the enable terminal receives the first enable signal, i.e., it is in the enabled state, it controls the first and second switches to close, and the input and output of the switch module are in a conducting state. At this time, if the control terminal receives the first level signal, it connects the first and third terminals; if the control terminal receives the second level signal, it connects the second and third terminals. When the enable terminal receives the second enable signal, i.e., it is in the disabled state, it controls the first and second switches to open, and the input and output of the switch module are in a blocked state. At this time, no matter how the level control signal received by the control terminal changes, the corresponding conducting channel cannot be connected.

[0014] In the over-temperature protection circuit of the above-mentioned air conditioning system, the output terminal of the voltage comparison module is also connected to the MCU module to output the level control signal to the MCU module.

[0015] It should be noted that by connecting the output of the voltage comparator module to the MCU module, a level control signal can be output to the MCU module. The MCU module can determine the conduction state of the switch module based on the level control signal, thereby identifying the IPM module corresponding to the currently received temperature signal. This facilitates the control of different IPM modules. For example, when the MCU module receives a first level signal from the voltage comparator module, it can determine that the switch module is conducting at both the first and third terminals, and the currently received temperature signal corresponds to the first temperature signal of the first IPM module. Therefore, the MCU module can control the operating state of the first IPM module based on the first temperature signal. Alternatively, when the MCU module receives a second level signal from the voltage comparator module, it can determine that the switch module is conducting at both the second and third terminals, and the currently received temperature signal corresponds to the second temperature signal of the second IPM module. Therefore, the MCU module can control the operating state of the second IPM module based on the second temperature signal.

[0016] In the over-temperature protection circuit of the above-mentioned air conditioning system, the switching module is provided with a conduction status output port connected to the MCU module.

[0017] It should be noted that by setting the on / off state output port of the switch module, a signal including the on / off state can be input to the MCU module. For example, a level control signal can be output to the MCU module. The MCU module can determine the on / off state of the switch module based on the level control signal, thereby determining the IPM module corresponding to the currently received temperature signal, which facilitates the control of different IPM modules.

[0018] In the over-temperature protection circuit of the above-mentioned air conditioning system, the first IPM module includes a first temperature detection circuit for outputting the first temperature signal; the second IPM module includes a second temperature detection circuit for outputting the second temperature signal.

[0019] The first IPM module is equipped with a first temperature detection circuit, which is used to output a first temperature signal. By connecting the output terminal of the first temperature detection circuit to a voltage comparison module, the first temperature signal can be input to the voltage comparison module. The second IPM module is equipped with a second temperature detection circuit, which is used to output a second temperature signal. By connecting the output terminal of the second temperature detection circuit to a voltage comparison module, the second temperature signal can be input to the voltage comparison module.

[0020] In the over-temperature protection circuit of the above-mentioned air conditioning system, controlling the operating state of the first IPM module according to the first temperature signal includes:

[0021] When the first temperature signal is greater than a preset temperature threshold, the switching frequency of the first IPM module is reduced.

[0022] It should be noted that when the MCU module receives the first temperature signal, it compares it with a preset temperature threshold. If the first temperature signal exceeds the preset threshold, it indicates that the operating temperature of the first IPM module is too high. In this case, the switching frequency of the first IPM module is reduced, i.e., the SVPWM signal of the first IPM module is adjusted. This reduces the switching losses of the first IPM module, effectively lowering its temperature and ensuring it operates within a normal temperature range. This protects the first IPM module and guarantees the reliability of the open-winding motor. The preset temperature threshold represents the extreme temperature. If the first temperature signal exceeds this extreme temperature, the IPM module will overheat, potentially damaging the switching devices and affecting the normal operation of the drive circuit.

[0023] In the over-temperature protection circuit of the above-mentioned air conditioning system, controlling the operating state of the second IPM module according to the second temperature signal includes:

[0024] When the second temperature signal is greater than the preset temperature threshold, the switching frequency of the second IPM module is reduced.

[0025] It should be noted that when the MCU module receives the second temperature signal, it compares the second temperature signal with the preset temperature threshold. If the second temperature signal is greater than the preset temperature threshold, it indicates that the operating temperature of the second IPM module is too high. In this case, the switching frequency of the second IPM module is reduced, that is, the SVPWM signal of the second IPM module is adjusted. This can reduce the switching loss of the second IPM module, thereby effectively reducing the temperature of the second IPM module and keeping it operating within the normal temperature range. This protects the second IPM module and ensures the reliability of the open-winding motor.

[0026] Secondly, embodiments of the present invention provide a circuit board including the over-temperature protection circuit described in the first aspect of the embodiments above.

[0027] The circuit board provided by the embodiments of the present invention has at least the following beneficial effects: the first IPM module outputs a first temperature signal to the input terminal of the voltage comparison module, and the second IPM module outputs a second temperature signal to the input terminal of the voltage comparison module. The voltage comparison module compares the received first temperature signal and second temperature signal and outputs a level control signal to the switch module. The switch module is connected to the first IPM module and the second IPM module respectively, and can determine the signal output state according to the level control signal. That is, the switch module can output the first temperature signal to the MCU module according to the level control signal, or output the second temperature signal to the MCU module according to the level control signal. The MCU module can control the working state of the first IPM module according to the first temperature signal, or control the working state of the second IPM module according to the second temperature signal, thereby achieving the effect of simultaneously monitoring the working state of the first IPM module and the second IPM module, reducing the hardware circuit design cost.

[0028] Thirdly, embodiments of the present invention provide an air conditioning system, including an over-temperature protection circuit as described in the first aspect embodiment above or a circuit board as described in the second aspect embodiment above.

[0029] The air conditioner system provided by the embodiments of the present invention has at least the following beneficial effects: the first IPM module outputs a first temperature signal to the input terminal of the voltage comparison module, and the second IPM module outputs a second temperature signal to the input terminal of the voltage comparison module. The voltage comparison module compares the received first temperature signal and second temperature signal and outputs a level control signal to the switch module. The switch module is connected to the first IPM module and the second IPM module respectively, and can determine the signal output state according to the level control signal. That is, the switch module can output the first temperature signal to the MCU module according to the level control signal, or output the second temperature signal to the MCU module according to the level control signal. The MCU module can control the working state of the first IPM module according to the first temperature signal, or control the working state of the second IPM module according to the second temperature signal, thereby achieving the effect of simultaneously monitoring the working state of the first IPM module and the second IPM module, reducing the hardware circuit design cost.

[0030] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the description, claims, and drawings. Attached Figure Description

[0031] The present invention will be further described below with reference to the accompanying drawings and embodiments;

[0032] Figure 1 This is a schematic diagram of the motor drive system provided in Embodiment 1 of the present invention;

[0033] Figure 2 This is a schematic diagram of the over-temperature protection circuit of the air conditioner system provided in Embodiment 2 of the present invention;

[0034] Figure 3 This is a schematic diagram of the over-temperature protection circuit of the air conditioner system provided in Embodiment 3 of the present invention;

[0035] Figure 4 This is a schematic diagram of the over-temperature protection circuit of the air conditioner system provided in Embodiment 4 of the present invention;

[0036] Figure 5 This is a schematic diagram of the over-temperature protection circuit of the air conditioner system provided in Embodiment 5 of the present invention;

[0037] Figure 6 This is a flowchart of the control method for the over-temperature protection circuit provided in Embodiment Six of the present invention;

[0038] Figure 7This is a diagram of the SVPWM signal of sector I of phase a under normal driving and adjustment switching state of the first IPM module under over-temperature conditions, provided in Embodiment 7 of the present invention.

[0039] Figure 8 This is a diagram of the SVPWM signal of sector I of phase a under normal driving and adjustment switching state of the second IPM module under over-temperature conditions, as provided in Embodiment 8 of the present invention. Detailed Implementation

[0040] This section will describe in detail specific embodiments of the present invention. Preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the drawings is to supplement the textual description with graphics, so that people can intuitively and vividly understand each technical feature and overall technical solution of the present invention, but they should not be construed as limiting the scope of protection of the present invention.

[0041] In the description of the embodiments of the present invention, "several" means one or more, "multiple" means two or more, "greater than," "less than," "exceeding," etc. are understood to exclude the number itself, while "above," "below," "within," etc. are understood to include the number itself. "At least one" refers to one or more, and "at least one of the following" and similar expressions refer to any combination of these items, including any combination of single or multiple items. If "first," "second," etc., are used in the description, they are only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance or implicitly indicating the number of indicated technical features or the order of the indicated technical features.

[0042] It should be noted that the terms "set," "install," and "connect" in the embodiments of this invention should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in the embodiments of this invention in conjunction with the specific content of the technical solution.

[0043] It should be noted that the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0044] This invention provides an over-temperature protection circuit, circuit board, and air conditioning system for an air conditioner system, which can simultaneously monitor the operating status of the first IPM module and the second IPM module, thereby reducing the cost of hardware circuit design.

[0045] The embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0046] like Figure 1As shown, the air conditioning system is equipped with a motor drive system to meet the working requirements of the air conditioning system. The motor drive system includes an open-winding motor 100, a first IPM module 200, and a second IPM module 300. The first IPM module 200 and the second IPM module 300 are respectively located on both sides of the open-winding motor 100. The open-winding motor 100 is driven by the coordinated control of the first IPM module 200 and the second IPM module 300 to ensure the normal operation of the open-winding motor 100.

[0047] like Figure 1 and Figure 2 As shown, a first aspect embodiment of the present invention provides an over-temperature protection circuit for an air conditioning system. The air conditioning system includes an open-winding motor 100, a first IPM module 200 and a second IPM module 300 disposed on both sides of the open-winding motor 100. The over-temperature protection circuit includes a voltage comparison module 400, a switching module 500 and an MCU module 600. The first IPM module 200 outputs a first temperature signal to the input terminal of the voltage comparison module 400, and the second IPM module 300 outputs a second temperature signal to the input terminal of the voltage comparison module 400. The voltage comparison module 400 is used to compare the first temperature signal and the second temperature signal and output the signal. The output level control signal is provided; the switch module 500 is connected to the voltage comparison module 400, the first IPM module 200 and the second IPM module 300 respectively. The switch module 500 is used to determine the signal output state according to the level control signal. The signal output state includes outputting a first temperature signal or outputting a second temperature signal; the MCU module 600 is connected to the switch module 500, the first IPM module 200 and the second IPM module 300 respectively. The MCU module 600 is used to control the working state of the first IPM module 200 according to the first temperature signal, or control the working state of the second IPM module 300 according to the second temperature signal.

[0048] It will be understood by those skilled in the art that Figure 1 The motor drive system shown in the figure and Figure 2 The over-temperature protection circuit shown does not constitute a limitation on the embodiments of the present invention. It may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0049] It should be noted that the open-winding motor 100 can be a permanent magnet synchronous machine (PMSM). The first IPM module 200 and the second IPM module 300 drive the open-winding motor 100 through a space vector pulse width modulation (SVPWM) signal. The main idea of ​​SVPWM is to use the ideal flux linkage circle of the stator of the three-phase symmetrical motor when powered by a three-phase symmetrical sinusoidal voltage as a reference standard, and to make appropriate switching according to the different switching modes of the three-phase inverter to form a PWM wave, and to use the actual flux linkage vector formed to track its accurate flux linkage circle.

[0050] The first IPM module 200 can output a first temperature signal T. IPM1 The first temperature signal reflects the operating status of the first IPM module 200. If the MCU module 600 receives the first temperature signal, it can determine whether the temperature of the first IPM module 200 is too high during operation, i.e., whether overheating has occurred. Similarly, the second IPM module 300 can output the second temperature signal T. IPM2 The second temperature signal can reflect the working status of the second IPM module 300. If the MCU module 600 receives the second temperature signal, it can determine whether the second IPM module 300 has overheated during operation. It should be noted that both the first and second temperature signals are voltage signals.

[0051] The over-temperature protection circuit of the air conditioner system provided in the first aspect embodiment above includes a first IPM module 200 outputting a first temperature signal to the input terminal of a voltage comparison module 400, and a second IPM module 300 outputting a second temperature signal to the input terminal of the voltage comparison module 400. The voltage comparison module 400 compares the received first and second temperature signals and outputs a level control signal to a switch module 500. The switch module 500 is connected to the first IPM module 200 and the second IPM module 300 respectively, and can determine the signal output state according to the level control signal. That is, the switch module 500 can output the first temperature signal to the MCU module 600 according to the level control signal, or output the second temperature signal to the MCU module 600 according to the level control signal. The MCU module 600 can control the working state of the first IPM module 200 according to the first temperature signal, or control the working state of the second IPM module 300 according to the second temperature signal, thereby achieving the effect of simultaneously monitoring the working state of the first IPM module 200 and the second IPM module 300, reducing the hardware circuit design cost.

[0052] Specifically, during motor drive system operation, by connecting the voltage comparison module 400 to the first IPM module 200 and the second IPM module 300 respectively, the voltage comparison module 400 can compare the received first and second temperature signals and output a level control signal. By connecting the output terminal of the voltage comparison module 400 to the switch module 500, the switch module 500 can input the first temperature signal to the MCU module 600 or the second temperature signal to the MCU module 600 according to the level control signal. When the MCU receives the first temperature signal, it controls the operating state of the first IPM module 200 according to the first temperature signal; when the MCU receives the second temperature signal, it controls the operating state of the second IPM module 300 according to the second temperature signal. Unlike the prior art scheme that separately detects different IPM modules and feeds back to the MCU module 600 through different ports, the over-temperature protection circuit of this embodiment can reduce the use of ports and simultaneously coordinate the control of the first IPM module 200 and the second IPM module 300.

[0053] It is understandable that by comparing the first temperature signal and the second temperature signal, different comparison results can be obtained. The comparison results include the first temperature signal being greater than the second temperature signal or the second temperature signal being greater than the first temperature signal. Different comparison results correspond to different level control signals, thereby determining different signal output states.

[0054] like Figure 3 As shown, in the over-temperature protection circuit of the above-mentioned air conditioning system, the switching module 500 includes a first terminal V1 connected to the output terminal of the first IPM module 200, a second terminal V2 connected to the output terminal of the second IPM module 300, a third terminal V3 connected as an output terminal to the MCU module 600, and a control terminal IN connected to the output terminal of the voltage comparison module 400; the level control signal includes a first level signal and a second level signal; when the control terminal IN receives the first level signal, the switching module 500 turns on the first terminal V1 and the third terminal V3; when the control terminal IN receives the second level signal, the switching module 500 turns on the second terminal V2 and the third terminal V3.

[0055] The switching module 500 includes a first terminal V1, a second terminal V2, a third terminal V3, and a control terminal IN. The first terminal V1 is connected to the output terminal of the first IPM module 200, the second terminal V2 is connected to the output terminal of the second IPM module 300, and the control terminal IN is connected to the output terminal of the voltage comparison module 400. The voltage comparison module 400 outputs a level control signal to the control terminal IN. The level control signal includes a first level signal and a second level signal. When the control terminal IN receives the first level signal from the voltage comparison module 400, the switching module 500 turns on the first terminal V1 and the third terminal V3, thereby inputting the first temperature signal output by the first IPM module 200 to the MCU module 600. When the control terminal IN receives the second level signal from the voltage comparison module 400, the switching module 500 turns on the second terminal V2 and the third terminal V3, thereby inputting the second temperature signal output by the second IPM module 300 to the MCU module 600.

[0056] It should be noted that the first level signal is a high level signal, and the second level signal is a low level signal. When the voltage comparison module 400 outputs a high level signal, the switch module 500 turns on the first terminal V1 and the third terminal V3, and the first temperature signal is input to the MCU module 600. When the voltage comparison module 400 outputs a low level signal, the switch module 500 turns on the second terminal V2 and the third terminal V3, and the second temperature signal is input to the MCU module 600. Alternatively, the first level signal is a low level signal, and the second level signal is a high level signal. When the voltage comparison module 400 outputs a low level signal, the switch module 500 turns on the first terminal V1 and the third terminal V3, and the first temperature signal is input to the MCU module 600. When the voltage comparison module 400 outputs a high level signal, the switch module 500 turns on the second terminal V2 and the third terminal V3, and the second temperature signal is input to the MCU module 600.

[0057] like Figure 3 As shown, in the over-temperature protection circuit of the above-mentioned air conditioning system, the voltage comparison module 400 includes a comparator 410. One input terminal of the comparator 410 is connected to the first IPM module 200 to obtain a first temperature signal, and the other input terminal of the comparator 410 is connected to the second IPM module 300 to obtain a second temperature signal. The output terminal of the comparator 410 is connected to the control terminal IN, and is used to output a first level signal when the first temperature signal is greater than the second temperature signal, and to output a second level signal when the second temperature signal is greater than the first temperature signal.

[0058] By setting a comparator 410 in the voltage comparison module 400 and connecting the two input terminals of the comparator 410 to the first IPM module 200 and the second IPM module 300 respectively, a first temperature signal and a second temperature signal can be obtained. The comparator 410 compares the first temperature signal and the second temperature signal and outputs a level control signal to the control terminal IN of the switch module 500. When the first temperature signal is greater than the second temperature signal, the comparator 410 outputs a first level signal. After receiving the first level signal, the control terminal IN of the switch module 500 conducts the first terminal V1 and the third terminal V3, thereby inputting the first temperature signal to the MCU module 600. When the second temperature signal is greater than the first temperature signal, the comparator 410 outputs a second level signal. After receiving the second level signal, the control terminal IN of the switch module 500 conducts the second terminal V2 and the third terminal V3, thereby inputting the second temperature signal to the MCU module 600.

[0059] It should be noted that during operation, the open-winding motor 100 is controlled in coordination by the first IPM module 200 and the second IPM module 300. The first IPM module 200 and the second IPM module 300 will influence each other. The first temperature signal and the second temperature signal are compared by the voltage comparison module 400, and the signal output state is adjusted by the switch module 500. The higher temperature signal is input to the MCU module 600, and the MCU module 600 controls the working state of the corresponding IPM module. For example, in the case of over-temperature, over-temperature protection measures are taken to reduce the temperature of the IPM module with the higher temperature, so as to ensure the stability of the open-winding motor 100.

[0060] In the over-temperature protection circuit of the above-mentioned air conditioning system, the switch module 500 also includes a first switch S1 connected in series between the first terminal V1 and the output terminal of the first IPM module 200, and a second switch S2 connected in series between the second terminal V2 and the output terminal of the second IPM module 300.

[0061] It should be noted that the first switch S1 is connected in series between the first terminal V1 and the output terminal of the first IPM module 200. When the first switch S1 is closed and the control terminal IN receives the first level signal, the first temperature signal can be turned on to flow to the first channel S1A of the MCU module 600. The first temperature signal is output from the output terminal of the first IPM module 200, flows sequentially through the first switch S1, the first terminal V1, and the third terminal V3, and is finally input into the MCU module 600. Similarly, when the second switch S2 is closed and the control terminal IN receives the second level signal, the second temperature signal can be turned on to flow to the second channel S2A of the MCU module 600. The second temperature signal is output from the output terminal of the second IPM module 300, flows sequentially through the second switch S2, the second terminal V2, and the third terminal V3, and is finally input into the MCU module 600.

[0062] like Figure 3 As shown, in the over-temperature protection circuit of the above-mentioned air conditioning system, the switch module 500 also includes an enable terminal EN; when the enable terminal EN receives a first enable signal, it controls the first switch S1 and the second switch S2 to close; when the enable terminal EN receives a second enable signal, it controls the first switch S1 and the second switch S2 to open.

[0063] It should be noted that the switch module 500 also has an enable terminal EN, which is used to determine the connection state of the input and output of the switch module 500. When the enable terminal EN receives the first enable signal, that is, it is in the enabled state, and controls the first switch S1 and the second switch S2 to close, and the input and output of the switch module 500 are in the conducting state. At this time, if the control terminal IN receives the first level signal, the first terminal V1 and the third terminal V3 are connected; if the control terminal IN receives the second level signal, the second terminal V2 and the third terminal V3 are connected. When the enable terminal EN receives the second enable signal, that is, it is in the disabled state, and controls the first switch S1 and the second switch S2 to open, and the input and output of the switch module 500 are in the blocked state. At this time, no matter how the level control signal received by the control terminal IN changes, the corresponding channel cannot be connected.

[0064] The following example uses a first enable signal that is low, a second enable signal that is high, a first level signal that is high, and a second level signal that is low.

[0065] As shown in Table 1 below, Table 1 is the logic table for determining the IPM temperature. EN represents the enable terminal; when the input state of EN is 0, it indicates that the first enable signal has been received; when the input state of EN is 1, it indicates that the second enable signal has been received. IN represents the control terminal; when the input state of IN is 1, it indicates that the first level signal has been received; when the input state of IN is 0, it indicates that the second level signal has been received. T IPM1 Indicates the first temperature signal; T IPM2 S1A represents the second temperature signal; S2A represents the first channel; S2A represents the second channel.

[0066] Specifically, when the enable terminal EN receives the first enable signal, if the first temperature signal is greater than the second temperature signal, the voltage comparison module 400 outputs a high-level signal to the control terminal IN of the switch module 500. The control terminal IN connects the first terminal V1 and the third terminal V3, that is, the first channel S1A is turned on, and the first temperature signal is input to the MCU module 600. If the second temperature signal is greater than the first temperature signal, the voltage comparison module 400 outputs a low-level signal to the control terminal IN of the switch module 500. The control terminal IN connects the second terminal V2 and the third terminal V3, that is, the second channel S2A is turned on, and the second temperature signal is input to the MCU module 600.

[0067] Table 1 Logic table for determining IPM temperature

[0068]

[0069] like Figure 4 As shown, in the over-temperature protection circuit of the above air conditioning system, the output terminal of the voltage comparison module 400 is also connected to the MCU module 600 to output the level control signal to the MCU module 600.

[0070] It should be noted that by connecting the output of the voltage comparator module 400 to the MCU module 600, a level control signal can be output to the MCU module 600. The MCU module 600 can determine the conduction state of the switch module 500 based on the level control signal, thereby determining the IPM module corresponding to the currently received temperature signal, facilitating the control of different IPM modules. For example, when the MCU module 600 receives a first level signal from the voltage comparator module 400, it can determine that the switch module 500 is conducting its first terminal V1 and third terminal V3, and the currently received temperature signal corresponds to the first temperature signal of the first IPM module 200. Therefore, the operating state of the first IPM module 200 is controlled based on the first temperature signal. Alternatively, when the MCU module 600 receives a second level signal from the voltage comparator module 400, it can determine that the switch module 500 is conducting its second terminal V2 and third terminal V3, and the currently received temperature signal corresponds to the second temperature signal of the second IPM module 300. Therefore, the operating state of the second IPM module 300 is controlled based on the second temperature signal.

[0071] In the over-temperature protection circuit of the air conditioning system described above, the switch module 500 is provided with an on-state output port connected to the MCU module 600.

[0072] It should be noted that by setting an on / off state output port in the switch module 500, a signal including the on / off state can be input to the MCU module 600. For example, a level control signal can be output to the MCU module 600. The MCU module 600 can determine the on / off state of the switch module 500 based on the level control signal, thereby determining the IPM module corresponding to the currently received temperature signal, which facilitates the control of different IPM modules.

[0073] like Figure 5 As shown, in the over-temperature protection circuit of the above-mentioned air conditioning system, the first IPM module 200 includes a first temperature detection circuit 210 for outputting a first temperature signal; the second IPM module 300 includes a second temperature detection circuit 310 for outputting a second temperature signal.

[0074] The first IPM module 200 is equipped with a first temperature detection circuit 210, which outputs a first temperature signal. By connecting the output of the first temperature detection circuit 210 to the voltage comparison module 400, the first temperature signal can be input to the voltage comparison module 400. Similarly, the output of the first temperature detection circuit 210 and the output of the second temperature detection circuit 310 can be connected to the voltage comparison module 400, allowing the first temperature signal to be input to the switch module 500.

[0075] It should be noted that the first temperature detection circuit is integrated into the first IPM module 200 and can detect the first temperature signal of the first IPM module 200 at any time, and the second temperature detection circuit is integrated into the second IPM module 300 and can detect the second temperature signal of the second IPM module 300 at any time.

[0076] In the over-temperature protection circuit of the aforementioned air conditioning system, the operating state of the first IPM module 200 is controlled according to the first temperature signal, including:

[0077] When the first temperature signal is greater than the preset temperature threshold, the switching frequency of the first IPM module 200 is reduced.

[0078] It should be noted that when the MCU module 600 receives the first temperature signal, it compares the first temperature signal with a preset temperature threshold. If the first temperature signal is greater than the preset temperature threshold, it indicates that the operating temperature of the first IPM module 200 is too high. Therefore, the switching frequency of the first IPM module 200 is reduced, i.e., the SVPWM signal of the first IPM module 200 is adjusted. This reduces the switching losses of the first IPM module 200, thereby effectively reducing its temperature and ensuring that the first IPM module 200 operates within its normal temperature range. This protects the first IPM module 200 and ensures the reliability of the open-winding motor 100. The preset temperature threshold represents the extreme temperature. If the first temperature signal is greater than the extreme temperature, it indicates that the IPM module is overheating, which may damage the switching devices and affect the normal operation of the drive circuit.

[0079] After reducing the switching frequency of the first IPM module 200, when the first temperature signal drops to less than or equal to the preset temperature threshold, the open winding motor 100 is driven according to the normal SVPWM signal.

[0080] Understandably, when the MCU module 600 receives the first temperature signal, it compares the first temperature signal with the preset temperature threshold. If the first temperature signal is less than or equal to the preset temperature threshold, it means that the first IPM module 200 is working within the normal temperature range and drives the open winding motor 100 according to the normal SVPWM signal.

[0081] In the over-temperature protection circuit of the aforementioned air conditioning system, the operating state of the second IPM module 300 is controlled according to the second temperature signal, including:

[0082] When the second temperature signal is greater than the preset temperature threshold, the switching frequency of the second IPM module 300 is reduced.

[0083] It should be noted that when the MCU module 600 receives the second temperature signal, it compares the second temperature signal with a preset temperature threshold. If the second temperature signal is greater than the preset temperature threshold, it indicates that the operating temperature of the second IPM module 300 is too high. In this case, the switching frequency of the second IPM module 300 is reduced, that is, the SVPWM signal of the second IPM module 300 is adjusted. This can reduce the switching loss of the second IPM module 300, thereby effectively reducing the temperature of the second IPM module 300 and keeping it operating within the normal temperature range. This protects the second IPM module 300 and ensures the reliability of the open-winding motor 100.

[0084] After reducing the switching frequency of the second IPM module 300, when the second temperature signal drops to less than or equal to the preset temperature threshold, the open winding motor 100 is driven according to the normal SVPWM signal.

[0085] Understandably, when the MCU module 600 receives the second temperature signal, it compares the second temperature signal with the preset temperature threshold. If the second temperature signal is less than or equal to the preset temperature threshold, it means that the second IPM module 300 is operating within the normal temperature range and drives the open winding motor 100 according to the normal SVPWM signal.

[0086] Unlike existing technologies where IPM modules shut down for protection when the temperature exceeds a threshold, this invention achieves cooling without shutting down by adjusting the SVPWM signal of the IPM module. This ensures that the open-winding motor 100 can operate normally for extended periods, thus improving the stability and reliability of the air conditioning system.

[0087] like Figure 6 As shown, the specific working process of the over-temperature protection circuit according to an embodiment of the present invention will be described below, and the control method of the over-temperature protection circuit is as follows:

[0088] 1. Upon startup, the first IPM module (IPM1) and the second IPM module (IPM2) output the first temperature signal T. IPM1 Second temperature signal T IPM2 ;

[0089] 2. Voltage comparison module compares T IPM1 and T IPM2 When T IPM1 >T IPM2 This indicates that the first temperature signal is greater than the second temperature signal. The voltage comparison module outputs a high-level signal 1 to the control terminal IN of the switch module, and the first channel S1A is turned on. IPM1 Input to the MCU module; when T IPM2 >T IPM1 The voltage comparator module outputs a low-level signal 0, the second channel S2A is turned on, and T... IPM2 Input is sent to the MCU module; in this embodiment, the IPM module operates at a temperature of -25℃ to 80℃. IPM1 T IPM2 The temperature display range (voltage signal) is 60℃ (2V) to 80℃ (2.5V).

[0090] 3. If T IPM1 Input is sent to the MCU module, and the MCU module compares T. IPM1 and preset temperature threshold T IPM极限 Determine T IPM1 >T IPM极限 When T IPM1 >T IPM极限 Adjusting the SVPWM signal controlling IPM1 reduces the switching losses of IPM1, thereby lowering the temperature of IPM1; if T IPM2 Input is sent to the MCU module, and the MCU module compares T. IPM2 and preset temperature threshold T IPM极限 Determine T IPM2 >T IPM极限 When T IPM2 >T IPM极限 Adjusting the SVPWM signal controlling IPM2 reduces the switching losses of IPM2, thereby lowering the temperature of IPM2; if T IPM1 ≤T IPM极限 Normal control of IPM1's SVPWM signal, or if T IPM2 ≤T IPM极限 The SVPWM signal of IPM2 is normally controlled; in this embodiment, T IPM极限 =75℃ (2.375V).

[0091] It should be noted that, in this embodiment of the invention, the voltage comparison module 400 compares the first temperature signal with the second temperature signal, and inputs the higher temperature signal into the MCU module 600. The MCU module 600 determines whether the input temperature signal is greater than a preset temperature threshold. If it is greater than the preset temperature threshold, the switching state of the corresponding IPM module is adjusted to reduce the switching loss of the IPM module, thereby reducing the temperature of the corresponding IPM module and ensuring the normal operation of the open winding motor 100.

[0092] like Figure 7 As shown, Figure 7 The image above shows the SVPWM signal diagram of sector I of phase a under normal driving conditions of the first IPM module (IPM1) under over-temperature conditions. Figure 7 The following is a diagram of the SVPWM signal of sector I of phase a when the first IPM module (IPM1) adjusts the switching state under over-temperature conditions, assuming that T is at this time. IPM1 >T IPM2 If IPM1 overheats, the SVPWM signal controlling IPM1 is adjusted to clamp the switching transistor of IPM1 into a certain switching state, reducing its switching loss. The second IPM module (IPM2) is also adjusted to ensure normal drive of the open winding motor 100.

[0093] like Figure 8 As shown, Figure 8 The image above shows the SVPWM signal diagram of sector I of phase a under normal driving conditions when the second IPM module (IPM2) is over-temperature. Figure 8 The following is a diagram of the SVPWM signal of sector I of phase a when the switching state is adjusted under over-temperature conditions of the second IPM module (IPM2), assuming that T is at this time. IPM2 >T IPM1 If IPM2 overheats, adjust the SVPWM signal of IPM2 to clamp the switching transistor of IPM2 into a certain switching state, reduce its switching loss, and adaptively adjust the first IPM module (IPM1) to ensure normal drive of the open winding motor 100.

[0094] A second aspect of the present invention provides a circuit board including the over-temperature protection circuit described in the first aspect embodiment above. A first IPM module 200 outputs a first temperature signal to the input terminal of a voltage comparison module 400, while a second IPM module 300 outputs a second temperature signal to the input terminal of the voltage comparison module 400. The voltage comparison module 400 compares the received first and second temperature signals and outputs a level control signal to a switch module 500. The switch module 500 is connected to both the first IPM module 200 and the second IPM module 300, and can determine the signal output state based on the level control signal. That is, the switch module 500 can output the first temperature signal to the MCU module 600 or the second temperature signal to the MCU module 600 based on the level control signal. The MCU module 600 can control the operating state of the first IPM module 200 or the second IPM module 300 based on the first temperature signal, thereby achieving the effect of simultaneously monitoring the operating states of the first IPM module 200 and the second IPM module 300, reducing hardware circuit design costs.

[0095] A third aspect of the present invention provides an air conditioner system, including an over-temperature protection circuit as described in the first aspect embodiment or a circuit board as described in the second aspect embodiment. A first IPM module 200 outputs a first temperature signal to the input terminal of a voltage comparison module 400, while a second IPM module 300 outputs a second temperature signal to the input terminal of the voltage comparison module 400. The voltage comparison module 400 compares the received first and second temperature signals and outputs a level control signal to a switch module 500. The switch module 500 is connected to both the first IPM module 200 and the second IPM module 300, and can determine the signal output state based on the level control signal. That is, the switch module 500 can output the first temperature signal to the MCU module 600 or the second temperature signal to the MCU module 600 based on the level control signal. The MCU module 600 can control the operating state of the first IPM module 200 or the second IPM module 300 based on the first temperature signal, thereby achieving the effect of simultaneously monitoring the operating states of the first IPM module 200 and the second IPM module 300, reducing hardware circuit design costs.

[0096] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0097] The above provides a detailed description of the preferred embodiments of the present invention. However, the present invention is not limited to the above embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention. All such equivalent modifications or substitutions are included within the scope defined by the claims of the present invention.

Claims

1. An over-temperature protection circuit for an air conditioning system, characterized in that, The air conditioning system includes an open-winding motor, a first IPM module and a second IPM module disposed on both sides of the open-winding motor, and the over-temperature protection circuit includes: A voltage comparison module is provided, wherein the first IPM module outputs a first temperature signal to the input terminal of the voltage comparison module, and the second IPM module outputs a second temperature signal to the input terminal of the voltage comparison module. The voltage comparison module is used to compare the first temperature signal and the second temperature signal and output a level control signal. A switching module is connected to the voltage comparison module, the first IPM module, and the second IPM module respectively. The switching module is used to determine the signal output state according to the level control signal. The signal output state includes outputting the first temperature signal or outputting the second temperature signal. The MCU module is connected to the switch module, the first IPM module, and the second IPM module respectively. The output terminal of the voltage comparison module is also connected to the MCU module to output the level control signal to the MCU module. The MCU module is used to determine the currently received temperature signal according to the level control signal, and control the working state of the first IPM module according to the first temperature signal, or control the working state of the second IPM module according to the second temperature signal.

2. The over-temperature protection circuit according to claim 1, characterized in that, The switching module includes a first terminal connected to the output terminal of the first IPM module, a second terminal connected to the output terminal of the second IPM module, a third terminal connected as an output terminal to the MCU module, and a control terminal connected to the output terminal of the voltage comparison module; the level control signal includes a first level signal and a second level signal; When the control terminal receives the first level signal, the switch module connects the first terminal and the third terminal; When the control terminal receives the second level signal, the switch module connects the second terminal and the third terminal.

3. The over-temperature protection circuit according to claim 2, characterized in that, The voltage comparison module includes a comparator. One input terminal of the comparator is connected to the first IPM module to obtain the first temperature signal, and the other input terminal of the comparator is connected to the second IPM module to obtain the second temperature signal. The output terminal of the comparator is connected to the control terminal and is used to output the first level signal when the first temperature signal is greater than the second temperature signal and to output the second level signal when the second temperature signal is greater than the first temperature signal.

4. The over-temperature protection circuit according to claim 2, characterized in that, The switching module further includes a first switch connected in series between the first terminal and the output terminal of the first IPM module, and a second switch connected in series between the second terminal and the output terminal of the second IPM module.

5. The over-temperature protection circuit according to claim 4, characterized in that, The switch module further includes an enable terminal; when the enable terminal receives a first enable signal, it controls the first switch and the second switch to close; when the enable terminal receives a second enable signal, it controls the first switch and the second switch to open.

6. The over-temperature protection circuit according to claim 2, characterized in that, The switch module is provided with an on / off output port connected to the MCU module.

7. The over-temperature protection circuit according to claim 1, characterized in that, The first IPM module includes a first temperature detection circuit for outputting the first temperature signal; the second IPM module includes a second temperature detection circuit for outputting the second temperature signal.

8. The over-temperature protection circuit according to claim 1, characterized in that, The step of controlling the operating state of the first IPM module according to the first temperature signal includes: When the first temperature signal is greater than a preset temperature threshold, the switching frequency of the first IPM module is reduced.

9. The over-temperature protection circuit according to claim 1, characterized in that, The step of controlling the operating state of the second IPM module according to the second temperature signal includes: When the second temperature signal is greater than the preset temperature threshold, the switching frequency of the second IPM module is reduced.

10. A circuit board, characterized in that, It includes an over-temperature protection circuit as described in any one of claims 1 to 9.

11. An air conditioning system, characterized in that, It includes an over-temperature protection circuit as described in any one of claims 1 to 9 or a circuit board as described in claim 10.

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