A stepping motor fault detection method, system and air conditioner

Abstract

The application provides a kind of stepper motor fault detection method, the stepper motor fault detection method is used to detect whether the fault of stepper motor or drive circuit occurs, the stepper motor fault detection method includes: obtaining the working state of stepper motor;Obtain drive IC current value I1;If the drive IC current value I1 is not equal to the normal current value in the working state of the stepper motor, then the single-chip microcomputer controls the failure indicating lamp to be bright.Compared with prior art, the stepper motor fault detection method of the application can effectively detect whether the fault of stepper motor or drive circuit occurs, which is convenient for reminding the staff of the abnormality of stepper motor or drive circuit and checking and repairing, to avoid the error of expansion valve movement angle causing air conditioner operation abnormality.

Description

Technical Field

[0001] This invention relates to the field of air conditioning, and more specifically, to a stepper motor fault detection method, system, and air conditioner. Background Technology

[0002] Expansion valves are now widely used in air conditioning system pressure regulation. The expansion valve is usually driven by a stepper motor. However, in the current technology, stepper motors usually use open-loop control. When the stepper motor has a short circuit, open circuit or other circuit abnormalities, the staff cannot know and cannot repair it in time. This will cause the expansion valve to move in the wrong angle, which will affect the system pressure and cause abnormal operation of the air conditioner.

[0003] In view of this, the present invention is hereby proposed. Summary of the Invention

[0004] The purpose of this invention is to propose a stepper motor fault detection method, system, and air conditioner to solve the problem in the prior art where when a stepper motor experiences a short circuit, open circuit, or other circuit abnormalities, the operator cannot know and cannot repair it in time, which leads to errors in the expansion valve's movement angle, thereby affecting the system pressure and causing abnormal air conditioner operation.

[0005] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0006] A stepper motor fault detection method is provided, which is used to detect whether a stepper motor and its drive circuit have malfunctioned. The stepper motor fault detection method includes:

[0007] Obtain the operating status of the stepper motor;

[0008] Obtain the current value I1 of the driver IC;

[0009] If the current value I1 of the driver IC is not equal to the normal current value of the stepper motor under working conditions, the microcontroller control fault indicator light will illuminate.

[0010] The stepper motor fault detection method described in this invention can effectively detect whether the stepper motor or drive circuit has malfunctioned, making it easy to remind staff of abnormalities in the stepper motor or drive circuit and to check and repair them, thus avoiding errors in the expansion valve's movement angle that could cause abnormal air conditioner operation.

[0011] Furthermore, the operating status of the stepper motor is obtained by detecting the low-level output of the four drive I / O channels of the microcontroller.

[0012] This setting makes it easy to obtain the operating status of the stepper motor.

[0013] Furthermore, the operating state of the stepper motor is obtained by detecting the low-level outputs of the four drive I / O channels of the microcontroller. Specifically, when all four drive I / O channels of the microcontroller output a low level, the stepper motor is in standby mode; when only one of the four drive I / O channels of the microcontroller outputs a low level, the stepper motor is operating in single-phase mode; and when two of the four drive I / O channels of the microcontroller output a low level, the stepper motor is operating in two-phase mode.

[0014] This setting facilitates the determination of the stepper motor's operating status based on the low-level output of the microcontroller's four drive I / O channels.

[0015] Furthermore, the normal current value of the stepper motor during operation specifically includes:

[0016] When the stepper motor is in standby mode, the normal current is 0; when the stepper motor is in single-phase operation, the current is... When the stepper motor operates in two-phase mode, the current is

[0017] This setting helps determine if the stepper motor or drive circuit is malfunctioning.

[0018] Furthermore, the current value I1 of the driver IC is obtained through a current detection circuit, and the current detection circuit feeds back the current value I1 of the driver IC to the microcontroller after obtaining it.

[0019] This setting facilitates the acquisition of the driver IC current value I1, which can then be compared with the normal current value of the stepper motor during operation, thereby determining whether the stepper motor or the drive circuit is malfunctioning.

[0020] In a second aspect, the present invention provides a stepper motor fault detection system, wherein the stepper motor fault detection system uses any one of the stepper motor fault detection methods described herein.

[0021] Furthermore, the stepper motor fault detection system includes a microcontroller, a driver IC, a stepper motor, and a fault indicator light. The microcontroller is connected to the driver IC and the fault indicator light, and the driver IC is also connected to the stepper motor. A current detection circuit is set between the microcontroller and the driver IC, and a voltage detection circuit is set between the microcontroller and the stepper motor.

[0022] This setting can effectively detect whether the expansion valve stepper motor or drive circuit is malfunctioning.

[0023] Furthermore, the current detection circuit is configured for single-resistor sampling.

[0024] This setting facilitates accurate detection of the stepper motor's operating current.

[0025] Furthermore, the stepper motor includes four phases, namely A, B, C, and D, and the microcontroller includes four drive I / O channels to control the conduction state of the four phases A, B, C, and D of the stepper motor respectively.

[0026] This setting facilitates precise control of the stepper motor by the microcontroller.

[0027] In a third aspect, the present invention provides an air conditioner that uses a stepper motor fault detection system as described in any one of the claims.

[0028] Compared with the prior art, the stepper motor fault detection method, system and air conditioner of the present invention can effectively detect whether the stepper motor or drive circuit has failed, which can help to remind staff to check and repair abnormalities in the stepper motor or drive circuit, and avoid abnormal operation of the air conditioner caused by incorrect movement angle of the expansion valve. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the structure of a stepper motor fault detection system according to an embodiment of the present invention;

[0030] Figure 2 This is a flowchart illustrating a stepper motor fault detection method according to an embodiment of the present invention.

[0031] Explanation of reference numerals in the attached figures:

[0032] 1. Microcontroller; 2. Driver IC; 3. Stepper motor; 4. Fault indicator light; 5. Current detection circuit; 6. Voltage detection circuit. Detailed Implementation

[0033] It should be noted that, unless otherwise specified, the embodiments and features described in the embodiments of the present invention can be combined with each other. The descriptions of "first," "second," etc., mentioned in the embodiments of the present invention are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0034] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0035] Example 1

[0036] This embodiment proposes a stepper motor fault detection method, which is used to detect whether a fault has occurred in the stepper motor 3 and its drive circuit. The stepper motor fault detection method includes:

[0037] Obtain the operating status of stepper motor 3;

[0038] Get the current value I1 of driver IC2;

[0039] If the current value I1 of the driver IC2 is not equal to the normal current value of the stepper motor 3 under the working state, the microcontroller 1 controls the fault indicator light 4 to light up.

[0040] The stepper motor fault detection method described in this embodiment can effectively detect whether the stepper motor 3 or the drive circuit has malfunctioned, which can help remind staff to check and repair the abnormal stepper motor 3 or the drive circuit, and avoid the expansion valve movement angle causing the air conditioner to malfunction.

[0041] Specifically, the operating state of the stepper motor 3 is obtained by detecting the low-level output of the four drive I / O channels of the microcontroller 1.

[0042] This setting facilitates the acquisition of the operating status of stepper motor 3.

[0043] Specifically, the operating state of the stepper motor 3 is obtained by detecting the low-level outputs of the four drive I / O channels of the microcontroller 1, including: when all four drive I / O channels of the microcontroller 1 output low level, the stepper motor 3 is in standby (not working); when only one of the four drive I / O channels of the microcontroller 1 outputs low level, the stepper motor 3 is operating in single-phase mode; when two of the four drive I / O channels of the microcontroller 1 output low level, the stepper motor 3 is operating in two-phase mode.

[0044] This setting facilitates the determination of the operating status of the stepper motor 3 based on the low-level output of the four drive I / O pins of the microcontroller 1.

[0045] Specifically, the stepper motor 3 includes four phases, namely A, B, C, and D, and the microcontroller 1 includes four drive I / O channels, which control the conduction state of the four phases A, B, C, and D of the stepper motor 3 respectively.

[0046] This setting facilitates precise control of the stepper motor 3 by the microcontroller 1.

[0047] More specifically, the stepper motor 3 includes four phases A, B, C, and D. Assuming the DC resistance of each phase is RX, the operating current of each phase is: Under normal operating conditions, the forward direction cycles through the four-phase eight-beat sequence A→AB→B→BC→C→CD→D→DA for a set number of steps; the reverse direction cycles through the sequence D→DC→C→CB→B→BA→A→AD for a set number of steps.

[0048] Specifically, the normal current value of the stepper motor 3 under operating conditions includes:

[0049] When the stepper motor 3 is in standby mode, its normal current is 0; when the stepper motor 3 is in single-phase operation, the current is... When the stepper motor 3 operates in two-phase mode, the current is

[0050] This setting helps determine if the stepper motor 3 or the drive circuit is malfunctioning.

[0051] Specifically, the current value I1 of the driver IC2 is obtained through the current detection circuit 5, and the current detection circuit 5 feeds back the current value I1 of the driver IC2 to the microcontroller 1 after obtaining it.

[0052] More specifically, this embodiment of a stepper motor fault detection method includes the following steps:

[0053] S1, Begin;

[0054] S2. Microcontroller 1 determines whether all four drive I / Os of microcontroller 1 are outputting low level; if yes, proceed to S3; if no, proceed to S5.

[0055] Step S2 determines whether all four drive I / Os of the microcontroller 1 output a low level, which helps to determine whether the stepper motor 3 is in standby (not working). When all four drive I / Os of the microcontroller 1 output a low level, the stepper motor 3 is in standby (not working).

[0056] S3, Detect the current value I1 of driver IC2;

[0057] Specifically, the current I1 of the driver IC2 (i.e., the operating current of the stepper motor 3) is detected by the current detection circuit 5.

[0058] S4. Microcontroller 1 determines whether the current I1 of driver IC2 is equal to 0; if yes, proceed to S12; if no, proceed to S11.

[0059] When the stepper motor 3 is in standby mode, the normal current value is 0. If the current value I1 = 0, it means that the stepper motor 3 is in standby mode and does not work, which is normal. Otherwise, if I1 ≠ 0, it means that the stepper motor 3 or the drive circuit is abnormal, and the microcontroller 1 controls the fault indicator light 4 to light up.

[0060] S5. Microcontroller 1 determines whether only one of its four driver I / O channels outputs a low level; if yes, proceed to S6; if no, proceed to S8.

[0061] Step S5 determines whether only one of the four drive I / O channels of the microcontroller 1 outputs a low level, which helps to determine whether the stepper motor 3 is operating in single-phase mode. When only one of the four drive I / O channels of the microcontroller 1 outputs a low level, the stepper motor 3 is operating in single-phase mode.

[0062] S6. Detect the current value I1 of driver IC2;

[0063] S7. Determine if the current I1 of driver IC2 is equal to... If yes, proceed to S12; otherwise, proceed to S11.

[0064] When the stepper motor 3 operates in single-phase mode, the current is... If the current value at this time This indicates that stepper motor 3 is working properly; otherwise... This indicates a problem with stepper motor 3 or its drive circuit, and microcontroller 1 will control fault indicator light 4 to illuminate.

[0065] S8. Microcontroller 1 determines whether two of its four driver I / O channels output a low level; if yes, proceed to S9; if no, proceed to S11.

[0066] Step S8 checks whether two of the four drive I / O channels of the microcontroller 1 output a low level. This helps determine whether the stepper motor 3 is operating in two-phase mode. When two of the four drive I / O channels of the microcontroller 1 output a low level, the stepper motor 3 is operating in two-phase mode. If the stepper motor 3 is neither in standby mode, nor in single-phase mode, nor in two-phase mode, it indicates a problem with the stepper motor 3 or its drive circuit, and the microcontroller 1 will control the fault indicator light 4 to illuminate.

[0067] S9, Detect the current I1 of driver IC2;

[0068] S10. Determine if the current I1 of driver IC2 is equal to... If yes, proceed to S12; otherwise, proceed to S11.

[0069] When the stepper motor 3 operates in two-phase mode, the current is If the current value at this time This indicates that stepper motor 3 is working properly; otherwise... This indicates a problem with stepper motor 3 or its drive circuit, and microcontroller 1 will control fault indicator light 4 to illuminate.

[0070] S11, the microcontroller 1 controls the fault indicator light 4 to light up;

[0071] The setting of step S11 is convenient for reminding staff of abnormalities in stepper motor 3 or drive circuit, so that staff can be aware of and inspect and repair in a timely manner, and avoid abnormal operation of air conditioner caused by incorrect movement angle of expansion valve.

[0072] S12, End.

[0073] Specifically, the stepper motor fault detection method uses the stepper motor fault detection system as described in any one of Embodiment 2 to detect whether the stepper motor 3 and the drive circuit have malfunctioned.

[0074] The stepper motor fault detection method described in this embodiment can effectively detect whether the stepper motor 3 or the drive circuit has malfunctioned through steps S1-S12, which can help remind staff to check and repair abnormalities in the stepper motor 3 or the drive circuit, and avoid errors in the movement angle of the expansion valve that could cause abnormal operation of the air conditioner.

[0075] During the execution of S12, step S1 is returned in real time.

[0076] This setting can detect whether the stepper motor 3 or the drive circuit is faulty in real time, which can help remind staff to check and repair abnormalities in the stepper motor 3 or the drive circuit, and avoid errors in the movement angle of the expansion valve that could cause abnormal operation of the air conditioner.

[0077] Example 2

[0078] This embodiment proposes a stepper motor fault detection system, which uses the stepper motor fault detection method described in any one of Embodiment 1.

[0079] The stepper motor fault detection system includes a microcontroller 1, a driver IC 2, a stepper motor 3, and a fault indicator light 4. The microcontroller 1 is connected to the driver IC 2 and the fault indicator light 4, respectively. The driver IC 2 is also connected to the stepper motor 3. A current detection circuit 5 is set between the microcontroller 1 and the driver IC 2, and a voltage detection circuit 6 is set between the microcontroller 1 and the stepper motor 3.

[0080] The stepper motor fault detection system described in this embodiment can effectively detect whether the stepper motor 3 or the drive circuit has malfunctioned, which can help remind staff to check and repair the abnormal stepper motor 3 or the drive circuit, and avoid the expansion valve's movement angle causing abnormal air conditioner operation.

[0081] The microcontroller 1 controls the driver IC 2 to drive the stepper motor 3. The stepper motor 3 is connected to the expansion valve and drives the expansion valve to move. The current detection circuit 5 detects the operating current of the stepper motor 3 and feeds it back to the microcontroller 1 after acquiring the operating current. The voltage detection circuit 6 detects the operating voltage of the stepper motor 3 and feeds it back to the microcontroller 1 after acquiring the operating voltage.

[0082] The fault indicator light 4 is used to indicate that the stepper motor 3 or the drive circuit is malfunctioning.

[0083] The current detection circuit 5 is configured for single-resistor sampling.

[0084] This setting facilitates accurate detection of the operating current of the stepper motor 3.

[0085] Specifically, the stepper motor 3 includes four phases, namely A, B, C, and D, and the microcontroller 1 includes four drive I / O channels, which control the conduction state of the four phases A, B, C, and D of the stepper motor 3 respectively.

[0086] This setting facilitates precise control of the stepper motor 3 by the microcontroller 1.

[0087] Specifically, the chip used for microcontroller 1 is not limited. In this embodiment, preferably, microcontroller 1 uses the ATMEGA48V chip, which is also the core component of this device. The ATMEGA48V chip microcontroller 1 is a high-performance, low-power 8-bit AVR microcontroller 1 with an advanced RISC architecture. It can be programmed with 131 instructions, most of which are executed in a single clock cycle. It has 32×8 general-purpose working registers, fully static operation, and achieves a performance of up to 16 MIPS when operating at 16MHz. The controller of the ATMEGA48V chip microcontroller 1 outputs a 4-phase, 8-beat pulse signal to drive the electronic expansion valve stepper motor 3, adjusting the valve opening degree and quickly controlling the refrigerant flow in the refrigeration system.

[0088] The stepper motor fault detection system described in this embodiment can effectively detect whether the stepper motor 3 or the drive circuit has malfunctioned, which can help remind staff to check and repair the abnormal stepper motor 3 or the drive circuit, and avoid the expansion valve's movement angle causing abnormal air conditioner operation.

[0089] Example 3

[0090] This embodiment proposes an air conditioner that uses a stepper motor fault detection method as described in any one of Embodiment 1 and a stepper motor fault detection system as described in Embodiment 2.

[0091] The air conditioner includes not only the stepper motor fault detection system but also other related components such as a condenser and a compressor. Since the specific structure and assembly relationship of these components are existing technologies, they will not be described in detail here.

[0092] The air conditioner described in this embodiment can effectively detect whether the stepper motor 3 or the drive circuit is faulty, which can help remind staff to check and repair abnormalities in the stepper motor 3 or the drive circuit, and avoid abnormal operation of the air conditioner caused by incorrect movement angle of the expansion valve.

[0093] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A stepper motor fault detection method, characterized in that, The stepper motor fault detection method is used to detect whether a fault has occurred in the stepper motor (3) or the drive circuit. The stepper motor fault detection method includes: Obtain the working status of the stepper motor (3); Obtain the current value I1 of the driver IC (2); If the current value I1 of the driver IC (2) is not equal to the normal current value of the stepper motor (3) under working conditions, the microcontroller (1) controls the fault indicator (4) to light up. The working state of the stepper motor (3) is obtained by the low level output of the four drive IOs of the single-chip microcomputer (1); The method is applied to the stepper motor fault detection system, which includes a microcontroller (1), a driver IC (2), a stepper motor (3), and a fault indicator (4). The microcontroller (1) is connected to the driver IC (2) and the fault indicator (4) respectively. The driver IC (2) is also connected to the stepper motor (3). A current detection circuit (5) is set between the microcontroller (1) and the driver IC (2), and a voltage detection circuit (6) is set between the microcontroller (1) and the stepper motor (3). The current detection circuit (5) is set to single-resistor sampling. The working state of the stepper motor (3) is obtained by the low-level output of the four drive IOs of the microcontroller (1). Specifically, when all four drive IOs of the microcontroller (1) output low level, the working state of the stepper motor (3) is standby; when only one of the four drive IOs of the microcontroller (1) outputs low level, the working state of the stepper motor (3) is single-phase operation; when two of the four drive IOs of the microcontroller (1) output low level, the working state of the stepper motor (3) is two-phase operation.

2. The stepper motor fault detection method according to claim 1, characterized in that, The normal current value of the stepper motor (3) under operating conditions specifically includes: When the stepper motor (3) is in standby mode, its normal current value is 0; when the stepper motor (3) is in single-phase operation, its current value is... When the stepper motor (3) is in two-phase operation, the current is 2. The DC resistance of each phase is R. X .

3. The stepper motor fault detection method according to claim 1, characterized in that, The current value I1 of the driver IC (2) is obtained by the current detection circuit (5). After obtaining the current value I1 of the driver IC (2), the current detection circuit (5) feeds back the current value I1 of the driver IC (2) to the microcontroller (1).

4. A stepper motor fault detection system, characterized in that, The stepper motor fault detection system uses a stepper motor fault detection method as described in any one of claims 1-3.

5. A stepper motor fault detection system according to claim 4, characterized in that, The stepper motor (3) has four phases, namely A, B, C and D. The microcontroller (1) has four drive I / O channels, which control the conduction state of the four phases A, B, C and D of the stepper motor (3).

6. An air conditioner, characterized in that, The air conditioner uses a stepper motor fault detection system as described in any one of claims 4-5.

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