Analog AC / DC motor control system for detecting air conditioner control panel

Abstract

The utility model provides an analog AC / DC motor control system for detecting an air conditioner control panel, which is characterized in that a DCPG motor driving signal receiving circuit is used for being respectively connected to an output signal end of a DCPG motor driving circuit of a detected control panel and is used for receiving a control signal sent by the DC motor driving circuit of the detected control panel or a PG of the detected control panel; the received signal level conversion circuit is connected with the DC motor driving signal receiving circuit and the PG motor driving signal receiving circuit and is used for converting a control signal into a level and inputting the level to the central processing unit for identification processing; the feedback signal output circuit is connected with the central processing unit through the output signal level conversion circuit, and the feedback signal is sent to the feedback input end of the DC motor drive circuit or the PG motor drive circuit of the tested control board after being converted into a level. According to the utility model, the working circuit simulating the DCPG motor is arranged to communicate with the DCPG motor driving circuit of the tested control board, and whether the circuit function of the tested control board is normal or not is judged through the central processing unit.

Description

Technical Field

[0001] The utility model relates to the technical field of air conditioner detection, and particularly relates to an analog AC / DC motor control system for detecting an air conditioner control board. Background Art

[0002] Traditional household air conditioners are generally divided into two parts: an indoor unit and an outdoor unit. Each part has a fan motor for blowing the cold or hot air inside the air conditioner outside the body to provide heat or cold air to the room. For different energy efficiency levels or different product series, the types of fan motors used are generally two types: DC motors (direct current motors) or PG motors (alternating current motors). Since the working principles of the two motors are different, the principles for the control board to drive them are also different. In the motor drive circuit detection process of the traditional control board, when detecting the control board, a motor with a corresponding function is plugged into its motor drive interface, and the working state of the motor is observed to see if it is normal or if a fault code indicating abnormal motor operation is reported, so as to determine whether the drive and feedback circuits of the control board are normal. The final determination of this detection method is made manually, which has a certain degree of uncertainty, is prone to missed detection or misjudgment, and affects the timeliness and stability of the production detection process. Once a functional abnormality occurs in the motor drive circuit of the control board, it is also easy to cause damage to the motor load, and the motor load needs to be replaced in time, resulting in a great waste of material and time costs.

[0003] Based on this, there is an urgent need for an analog AC / DC motor control circuit that can be compatible with DC motors and PG motors and detect their drive circuits. Summary of the Utility Model

[0004] To solve the above problems, the utility model aims to provide an analog AC / DC motor control system for detecting an air conditioner control board. By setting up a working circuit that simulates DC / PG motors and communicating with the DC / PG motor drive circuit of the control board to be tested, the central processing unit is used to determine whether the circuit function of the control board to be tested is normal, simplifying the detection process of the DC / PG motor drive circuit of the control board to be tested and avoiding the actual operation of the DC / PG motor load.

[0005] To achieve the above object, the technical solution of the utility model is realized as follows:

[0006] An analog AC and DC motor control system for detecting an air conditioner control board, comprising a DC motor drive signal receiving circuit, a PG motor drive signal receiving circuit, a received signal level conversion circuit, an output signal level conversion circuit, a feedback signal output circuit, and a central processing unit. The DC motor drive signal receiving circuit and the PG motor drive signal receiving circuit are respectively used to connect to the output signal terminals of the DC motor drive circuit and the PG motor drive circuit of the control board to be measured, and are used to receive the control signals sent by the DC motor drive circuit or the PG of the control board to be measured. The received signal level conversion circuit is connected to the DC motor drive signal receiving circuit and the PG motor drive signal receiving circuit, and is used to convert the level of the control signal and then input it to the central processing unit for identification and processing. The feedback signal output circuit is connected to the central processing unit through the output signal level conversion circuit, and is used to convert the level of the feedback signal processed by the central processing unit and then send it to the feedback input terminals of the DC motor drive circuit or the PG motor drive circuit of the control board to be measured.

[0007] Further, the PG motor drive signal receiving circuit includes a receiving port CN1, a step-down resistor R8, a step-down resistor R9, a step-down resistor R10, a current-limiting resistor R1, a forward clamping diode D1, a reverse clamping diode D2, and a resistor R2. The receiving port CN1 is sequentially connected to the step-down resistor R8, the step-down resistor R9, the step-down resistor R10, the current-limiting resistor R1, and the forward clamping diode D1 in parallel with the reverse clamping diode D2 and the resistor R2. The DC motor drive signal receiving circuit includes a receiving port CN3, and the receiving port CN3 is sequentially connected to the current-limiting resistor R1, the forward clamping diode D1 in parallel with the reverse clamping diode D2, and the resistor R2.

[0008] Further, the received signal level conversion circuit includes an optocoupler U1, a pull-up resistor R3, a current-limiting resistor R4, and a pull-down capacitor C1. The primary of the optocoupler U1 is connected to the reverse clamping diode D2 and the resistor R2 in parallel. A current-limiting resistor R4 and a pull-down capacitor C1 are connected between the secondary of the optocoupler U1 and the central processing unit to form a resistor-capacitor low-pass filter circuit. The secondary signal port of the optocoupler U1 is connected to the pull-up resistor R3 and is connected to +3.3V DC.

[0009] Further, the output signal level conversion circuit includes an optocoupler U2, a pull-up resistor R7, and a driving triode T1. The driving triode T1 is connected between the primary of the optocoupler U2 and the central processing unit. The primary input terminal of the optocoupler U2 is connected to the pull-up resistor R7 and is connected to +3.3V DC.

[0010] Further, the feedback signal output circuit includes an output port CN2, a protection resistor R5, and a current-limiting resistor R6. A protection resistor R5 and a current-limiting resistor R6 are connected in parallel between the secondary of the optocoupler U2 and the output port CN2.

[0011] Further, the forward clamping diode D1 and the reverse clamping diode D2 are of the model GS1M, the optocoupler U1 is of the model PC817C, the optocoupler U2 is of the model PC817, and the driving triode T1 is of the model LMUN2232.

[0012] Beneficial effects: By setting up a working circuit to simulate a DC / PG motor and communicating with the DC / PG motor drive circuit of the control board under test, the central processing unit is used to determine whether the circuit function of the control board under test is normal, simplifying the detection process of the DC / PG motor drive circuit of the control board under test and avoiding the actual operation of the DC / PG motor load. Description of the Drawings

[0013] The drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments and descriptions thereof of the present invention are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0014] Figure 1 is a structural function schematic diagram of the analog AC / DC motor control system for detecting an air conditioner control board according to an embodiment of the present invention;

[0015] Figure 2 is a circuit diagram of the analog AC / DC motor control system for detecting an air conditioner control board according to an embodiment of the present invention. Detailed Embodiments

[0016] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0017] Embodiment 1

[0018] See Figure 1-2: An analog AC / DC motor control system for detecting an air conditioner control board, comprising a DC motor drive signal receiving circuit, a PG motor drive signal receiving circuit, a received signal level conversion circuit, an output signal level conversion circuit, a feedback signal output circuit, and a central processing unit. The DC motor drive signal receiving circuit and the PG motor drive signal receiving circuit are respectively used to connect to the output signal terminals of the DC motor drive circuit and the PG motor drive circuit of the control board to be measured, and are used to receive the control signals sent by the DC motor drive circuit or the PG of the control board to be measured. The received signal level conversion circuit is connected to the DC motor drive signal receiving circuit and the PG motor drive signal receiving circuit, and is used to convert the control signal level and then input it to the central processing unit for identification and processing. The feedback signal output circuit is connected to the central processing unit through the output signal level conversion circuit, and is used to convert the feedback signal processed by the central processing unit and then send it to the feedback input terminals of the DC motor drive circuit or the PG motor drive circuit of the control board to be measured.

[0019] In this embodiment, by setting up the working circuits of the analog DC / PG motors to communicate with the DC / PG motor drive circuits of the control board to be measured, the central processing unit is used to judge whether the circuit functions of the control board to be measured are normal, simplifying the detection process of the DC / PG motor drive circuits of the control board to be measured and avoiding the actual operation of the DC / PG motor loads.

[0020] It should be noted that in this embodiment, the DC / PG motor drive circuits of the control board to be measured need to be detected separately, and the DC / PG motor drive circuits cannot be detected simultaneously to prevent mutual interference and reduce the detection accuracy.

[0021] In a specific example, the PG motor drive signal receiving circuit includes a receiving port CN1, a step-down resistor R8, a step-down resistor R9, a step-down resistor R10, a current-limiting resistor R1, a forward clamping diode D1, a reverse clamping diode D2, and a resistor R2. The receiving port CN1 is sequentially connected to the step-down resistor R8, the step-down resistor R9, the step-down resistor R10, the current-limiting resistor R1, and the forward clamping diode is connected in parallel with the reverse clamping diode D2 and the resistor R2. The DC motor drive signal receiving circuit includes a receiving port CN3, and the receiving port CN3 is sequentially connected to the current-limiting resistor R1, the forward clamping diode D1 is connected in parallel with the reverse clamping diode D2 and the resistor R2.

[0022] It should be noted that the PG motor drive signal receiving circuit and the DC motor drive signal receiving circuit in this embodiment share the current-limiting resistor R1, the forward clamping diode D1, the parallel-connected reverse clamping diode D2, and the resistor R2. The parallel-connected reverse clamping diode D2 and the resistor R2 are used to protect the received signal level conversion circuit. The receiving ports CN1 and CN3 in this embodiment are respectively used to connect to the PG motor drive circuit and the DC motor drive circuit of the control board to be measured, improving the adaptability and compatibility of the detection.

[0023] In a specific example, the received signal level conversion circuit includes an optocoupler U1, a pull-up resistor R3, a current-limiting resistor R4, and a pull-down capacitor C1. The primary of the optocoupler U1 is connected to the parallel-connected reverse clamping diode D2 and the resistor R2. A current-limiting resistor R4 and a pull-down capacitor C1 are connected between the secondary of the optocoupler U1 and the central processing unit to form a resistor-capacitor low-pass filter circuit. The secondary signal port of the optocoupler U1 is connected to the pull-up resistor R3 and is connected to +3.3V DC.

[0024] This embodiment can ensure the stability and correctness of the output signal of the secondary of the optocoupler U1.

[0025] In a specific example, the output signal level conversion circuit includes an optocoupler U2, a pull-up resistor R7, and a driving triode T1. A driving triode T1 is connected between the primary of the optocoupler U2 and the central processing unit. The primary input terminal of the optocoupler U2 is connected to the pull-up resistor R7 and is connected to +3.3V DC.

[0026] The driving triode T1 in this embodiment is used to send a feedback square wave signal. The pull-up resistor R7 is used to protect the circuit and ensure the stable conduction and cut-off of the driving triode.

[0027] In a specific example, the feedback signal output circuit includes an output port CN2, a protection resistor R5, and a current-limiting resistor R6. A protection resistor R5 and a current-limiting resistor R6 are connected in parallel between the secondary of the optocoupler U2 and the output port CN2.

[0028] In a specific example, the model of the forward clamping diode D1 and the reverse clamping diode D2 is GS1M, the model of the optocoupler U1 is PC817C, the model of the optocoupler U2 is PC817, and the model of the driving triode T1 is LMUN2232.

[0029] In this example, the diode D1 and D2 are of the GS1M model. D1 can protect the primary of the optocoupler U1 to conduct reliably during the high-level part of the square wave signal. And in cooperation with the voltage-dividing resistors R8, R9, R10, the current-limiting resistor R1, the reverse clamping diode D2, and the parallel resistor R2, it can protect the optocoupler U1 from damage. The optocoupler U1 is of the PC817C model; when the primary of the optocoupler U1 conducts and cuts off, a square wave signal with corresponding frequency and duty cycle can be obtained and input to the CPU, which is received and analyzed by the main control unit. The T1 triode is of the LMUN2232 model, and its internal self-limiting current and pull-down resistors are used to protect its internal structure from damage; the U2 is of the PC817 model. For the square wave signal sent by the CPU, the high and low level changes can be achieved through the conduction and cut-off of T1 and U2, and a square wave signal with corresponding frequency and duty cycle is output to the signal receiving circuit of the control board under test. Thus, an analog detection circuit and a communication signal loop of the control board under test are formed to analyze the signal and determine whether the circuit function of the control board under test is normal.

[0030] The process of the analog DC motor control circuit of this embodiment for detecting the drive circuit of the air conditioner control board includes the following steps:

[0031] Step 1: Connect the strong power ground DGND pin, drive signal VSP pin, feedback signal FB pin, VCC-OUT (+15V) pin, and GND-OUT pin in the motor drive circuit of the control board under test to the receiving port CN3 and the output port CN2;

[0032] Step 2: During the detection process, the motor drive signal sent by the control board under test, after passing through the optocoupler U1 of the analog DC motor control circuit, will be converted from the original high-level signal (+15V) to a low-level signal (+3.3V) that meets the CPU working requirements;

[0033] Step 3: After the CPU receives the drive signal of the control board under test, it will send a corresponding feedback signal to the control board under test. This signal is a low-level signal (+3.3V), which needs to pass through the optocoupler U2 of the detection circuit to convert it into a high-level signal (+15V) that meets the feedback circuit of the control board under test;

[0034] Step 4: During the detection process, if the CPU detects that the drive signal and feedback signal of the control board under test reach balance and no longer fluctuate, it is determined that the DC motor drive circuit of the control board under test is normal.

[0035] The working principle of the analog DC motor control circuit in this embodiment for detecting the drive circuit of the air conditioner control board is as follows. First, connect the motor drive circuit ports of the control board under test to ports CN1 and CN3. When starting the detection, according to the working principle of the DC motor, the control board under test sends a PWM square wave signal corresponding to the required speed to the receiving port CN3 of the analog detection circuit through the DC motor drive circuit. In the high-level effective voltage part of the square wave signal, the primary diode of the optocoupler U1 conducts, and current flows through it, causing the output terminal of the optocoupler U1 to conduct and output a low level; while in the low-level signal part of the square wave signal received by CN3, the current of the primary diode of the optocoupler is cut off, causing the output terminal of the optocoupler to close and output a low level; thus, the CPU unit of the analog circuit receives the motor drive signal of the control board under test that has been converted. After the CPU unit receives the speed drive square wave signal of the control board under test, according to the parsed speed requirement, it sends a feedback square wave signal with a corresponding duty cycle. When reverse driving the triode T1 and the signal output by the CPU is in the high-level part, the reverse driving triode T1 outputs a low level; when the primary of the optocoupler U2 detects the low level output by the triode T1, the internal primary diode conducts, and current flows through it, causing the output terminal of the optocoupler to conduct and output a low level; while when the signal output by the CPU is in the low-level part, the reverse driving triode T1 is cut off, and the output terminal is floating; when the primary of the optocoupler U2 detects the floating signal output by the triode T1, the current of the internal primary diode is cut off, causing the output terminal of the optocoupler to cut off and output a high level; thus, the feedback square wave signal output by the CPU can be sent to the feedback receiving circuit of the control board under test; the CPUs of the control board under test and the analog detection circuit jointly analyze the input and output square wave signals. When reaching the required balance state, the CPU of the analog detection circuit determines that the DC motor working circuit of the control board under test is normal.

[0036] The process of the analog PG motor control circuit in this embodiment for detecting the drive circuit of the air conditioner control board includes the following steps:

[0037] Step 1: Connect the fan drive FAN-L pin, neutral line ACN pin, feedback signal FB pin, VCC-OUT (+5V) pin, and feedback signal ground GND-OUT pin in the motor drive circuit of the control board under test to the corresponding terminals CN1 and CN2;

[0038] Step 2: During the detection process, the motor drive signal sent by the main board under test is divided and limited in current by the resistors R7, R8, R9, and R10 of the detection circuit, and then the effective voltage of the drive signal transmitted to the primary of the optocoupler is reduced to a voltage value within the withstand voltage range of the optocoupler to ensure the normal operation of the circuit; then, the high-level signal (+15V) of the primary is converted into a low-level signal (+3.3V) that meets the CPU operation through the optocoupler;

[0039] Step 3: After the CPU receives the drive signal of the control board under test, it will send a corresponding feedback signal to the control board under test. This signal is a low-level signal (+3.3V), and it needs to pass through the optocoupler U2 of the detection circuit to convert it into a high-level signal (+5V) that meets the feedback circuit of the control board under test.

[0040] Step 4: During the detection process, if the detection tooling detects that the drive signal and feedback signal of the control board under test reach equilibrium and no longer fluctuate, it is determined that the PG motor drive circuit of the control board under test is normal.

[0041] The working principle of the analog PG motor control circuit in this embodiment for detecting the drive circuit of the air conditioner control board is as follows. First, connect the motor drive circuit port of the control board under test to the ports CN1 and CN2 of the analog detection circuit. When starting the detection, according to the working principle of the PG motor, the control board under test sends a PWM square wave signal corresponding to the required speed to the receiving port CN1 of the analog detection circuit through the PG motor drive circuit. In the high-level effective voltage part of the square wave signal, first, the signal is divided by three voltage-dividing resistors, causing the primary diode of the optocoupler U1 to conduct, and current flows through, making the output end of the optocoupler conduct and output a low level. In the low-level signal part of the square wave signal received by CN1, the current of the primary diode of the optocoupler is cut off, causing the output end of the optocoupler to close and output a low level. Thus, the CPU unit of the analog circuit receives the converted motor drive signal of the control board under test. After the CPU unit receives the speed drive square wave signal of the control board under test, according to the parsed speed requirement, it sends a feedback square wave signal with a corresponding duty cycle. When reverse driving the triode T1 and the signal output by the CPU is at the high-level part, the reverse driving triode T1 outputs a low level. When the primary of the optocoupler U2 detects the low level output by the triode T1, the internal primary diode conducts, and current flows through, making the output end of the optocoupler conduct and output a low level. When the signal output by the CPU is at the low-level part, the reverse driving triode T1 is cut off, and the output end is floating. When the primary of the optocoupler U2 detects the floating signal output by the triode T1, the current of the internal primary diode is cut off, causing the output end of the optocoupler to cut off and output a high level. Thus, the feedback square wave signal output by the CPU can be sent to the feedback receiving circuit of the control board under test. The CPUs of the control board under test and the analog detection circuit jointly analyze the input and output square wave signals. When reaching the required equilibrium state, the CPU of the analog detection circuit determines that the PG motor working circuit of the control board under test is normal.

[0042] The above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A simulated AC and DC motor control system for detecting an air conditioning control panel, characterized in that: It includes a DC motor drive signal receiving circuit, a PG motor drive signal receiving circuit, a receiving signal level conversion circuit, an output signal level conversion circuit, a feedback signal output circuit and a central processing unit. The DC motor drive signal receiving circuit and the PG motor drive signal receiving circuit are used to be connected to the output signal ends of the DC motor drive circuit and the PG motor drive circuit of the control board under test, respectively, and are used to receive the control signal sent by the DC motor drive circuit or the PG of the control board under test; the receiving signal level conversion circuit is connected to the DC motor drive signal receiving circuit and the PG motor drive signal receiving circuit to convert the control signal level and input it to the central processing unit for identification processing; the feedback signal output circuit is connected to the central processing unit through the output signal level conversion circuit to convert the feedback signal processed by the central processing unit and send it to the feedback input end of the DC motor drive circuit or the PG motor drive circuit of the control board under test after the level conversion.

2. The simulated AC and DC motor control system for detecting an air conditioning control panel according to claim 1, characterized in that: The PG motor drive signal receiving circuit includes a receiving port CN1, a step-down resistor R8, a step-down resistor R9, a step-down resistor R10, a current limiting resistor R1, a forward clamping diode D1, a reverse clamping diode D2 and a resistor R2; the receiving port CN1 is connected in sequence to the step-down resistor R8, the step-down resistor R9, the step-down resistor R10, the current limiting resistor R1, the forward clamping diode connected in parallel with the reverse clamping diode D2 and the resistor R2; the DC motor drive signal receiving circuit includes a receiving port CN3, and the receiving port CN3 is connected in sequence to the current limiting resistor R1, the forward clamping diode D1 connected in parallel with the reverse clamping diode D2 and the resistor R2.

3. The simulated AC and DC motor control system for detecting an air conditioning control panel according to claim 2, characterized in that: The receiving signal level conversion circuit includes a photocoupler U1, a pull-up resistor R3, a current limiting resistor R4, and a pull-down capacitor C1. The primary of the photocoupler U1 is connected to a reverse clamping diode D2 and a resistor R2 in parallel. The secondary of the photocoupler U1 is connected to a central processing unit via a current limiting resistor R4 and a pull-down capacitor C1 to form a resistor-capacitor low-pass filter circuit. The secondary signal port of the photocoupler U1 is connected to the pull-up resistor R3 and connected to +3.3V DC.

4. The simulated AC and DC motor control system for detecting an air conditioning control panel according to claim 1, characterized in that: The output signal level conversion circuit includes a photocoupler U2, a pull-up resistor R7, and a driving transistor T1. The driving transistor T1 is connected between the primary of the photocoupler U2 and the central processing unit, and the primary input end of the photocoupler U2 is connected to the pull-up resistor R7 and connected to +3.3V DC.

5. The simulated AC and DC motor control system for detecting an air conditioning control panel according to claim 4, characterized in that: The feedback signal output circuit includes an output port CN2, a protection resistor R5, and a current limiting resistor R6. The protection resistor R5 and the current limiting resistor R6 are connected in parallel between the secondary of the photocoupler U2 and the output port CN2.

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