Phase sequence detection device of PWM (Pulse Width Modulation) control mode

Abstract

The utility model provides a PWM control mode phase sequence detection device comprising a signal acquisition module, a signal conversion module, a phase sequence detection module and a power supply module, the signal acquisition module is connected with the signal conversion module, the signal conversion module is connected with the phase sequence detection module, and the power supply module is connected with the phase sequence detection module. The power supply module is respectively connected with the signal acquisition module, the signal conversion module and the phase sequence detection module, the signal acquisition module is connected with a three-phase wiring end of a to-be-detected device through a UVW three-phase wiring, and the signal acquisition module is used for acquiring a PWM driving signal of the to-be-detected device and inputting the PWM driving signal to the signal conversion module; the signal conversion module converts the PWM driving signal into a PWM sine and cosine waveform signal and inputs the PWM sine and cosine waveform signal to the phase sequence detection module, and the phase sequence detection module receives the PWM sine and cosine waveform signal and then is used for completing phase sequence detection of the to-be-detected equipment. The phase sequence detection circuit has the effect of accurately realizing phase sequence detection.

Description

Technical Field

[0001] The utility model belongs to the technical field of motor detection, and in particular relates to a phase sequence detection device in a PWM control mode. Background Art

[0002] Three-phase alternating current is a form of electric energy transmission, referred to as three-phase electricity. A three-phase AC power supply is a power supply composed of three AC potentials with the same frequency, equal amplitude, and phase difference of 120°. Three-phase AC power has many uses. Most AC power equipment in industry, such as motors, use three-phase AC power. Once the phase sequence is connected incorrectly during engineering wiring, it will have a serious impact on the load. Therefore, in the industrial field, the phase sequence of the three-phase power supply needs to be detected before connecting to the three-phase power. Taking the motor control system of new energy vehicles as an example, when the U, V, and W three-phase wiring harnesses of the three-phase drive motor (including the main drive and the air pump / oil pump auxiliary drive unit) are misaligned, the motor will change from forward to reverse, resulting in abnormal operation of the vehicle or the air pump / oil pump, and even causing safety accidents.

[0003] Normally, after the motor is assembled, visual inspection or one-to-one measurement with a multimeter is used to check the correctness of the wiring harness assembly. Although the above solution is low-cost, it has certain defects. During the wiring harness production process, the connection of a single wire in the phase is misaligned, that is, the wiring harness of the right connector is misaligned. Because this link mainly uses visual methods to detect the consistency of the wiring harness mark and the connector jack, it is inevitable that human errors will cause phase misalignment. Utility Model Content

[0004] The utility model provides a phase sequence detection device in a PWM control mode, so as to solve the problem that the existing phase sequence detection mode is prone to detection errors due to human errors.

[0005] The phase sequence detection device of PWM control mode provided by the utility model comprises: a signal acquisition module, a signal conversion module, a phase sequence detection module and a power supply module, wherein the signal acquisition module is connected to the signal conversion module, the signal conversion module is connected to the phase sequence detection module, the power supply module is respectively connected to the signal acquisition module, the signal conversion module and the phase sequence detection module, the signal acquisition module is connected to the three-phase terminal of the device under test through UVW three-phase wiring, the signal acquisition module is used to acquire the PWM drive signal of the device under test, and input the PWM drive signal to the signal conversion module, the signal conversion module converts the PWM drive signal into a PWM sine-cosine waveform signal, and inputs the PWM sine-cosine waveform signal into the phase sequence detection module, and the phase sequence detection module is used to complete the phase sequence detection of the device under test after receiving the PWM sine-cosine waveform signal.

[0006] Optionally, the phase sequence detection module includes a bypass unit, an optocoupler unit and an inverted phase detection unit, the bypass unit is connected to the output end of the signal conversion module, the optocoupler unit is connected to the bypass unit, the inverted phase detection unit is connected to the optocoupler unit, and the inverted phase detection unit is used to output the phase sequence detection result.

[0007] Optionally, the bypass unit includes a first resistor R1, a second resistor R2, a first diode D1, a second diode D2, a third diode D3 and a fourth diode D4, and the optical coupling unit includes a first optical coupler U1 and a second optical coupler U2, and the first optical coupler U1 and the second optical coupler U2 each include two input terminals and two output terminals;

[0008] One end of the first resistor R1 is connected to the first output end of the signal conversion module, the other end of the first resistor R1 is connected to the cathode of the first diode D1, the anode of the first diode D1 is respectively connected to the anode of the second diode D2 and the second input end of the first optical coupler U1, the cathode of the second diode D2 is respectively connected to the second output end of the signal conversion module and the first input end of the first optical coupler U1, the first output end of the first optical coupler U1 is connected to the anti-phase detection unit, and the second output end of the first optical coupler U1 is connected to the power supply module;

[0009] One end of the second resistor R2 is connected to the third output end of the signal conversion module, the other end of the second resistor R2 is connected to the cathode of the third diode D3, the anode of the third diode D3 is respectively connected to the anode of the fourth diode D4 and the second input end of the second optical coupler U2, the cathode of the fourth diode D4 is respectively connected to the second output end of the signal conversion module and the first input end of the second optical coupler U2, the first output end of the second optical coupler U2 is connected to the anti-phase detection unit, and the second output end of the second optical coupler U2 is connected to the power supply module.

[0010] Optionally, the anti-phase detection unit includes a third resistor R3, a fourth resistor R4, a first inverter A1, a second inverter A2 and an anti-phase detection chip, one end of the third resistor R3 is connected to the first output end of the first optical coupler U1, the other end of the third resistor R3 is connected to the input end of the first inverter A1, the output end of the first inverter A1 is connected to the first input end of the anti-phase detection chip, one end of the fourth resistor R4 is connected to the first output end of the second optical coupler U2, the other end of the fourth resistor R4 is connected to the input end of the second inverter A2, the output end of the second inverter A2 is connected to the second input end of the anti-phase detection chip, and the anti-phase detection chip outputs the phase sequence detection result through the output end.

[0011] Optionally, the phase sequence detection module further includes a first filtering unit and a second filtering unit, wherein the first filtering unit is connected between the first optical coupler U1 and the first inverter A1, and the second filtering unit is connected between the second optical coupler U2 and the second inverter A2.

[0012] Optionally, the first filtering unit includes a fifth resistor R5 and a first capacitor C1, one end of the fifth resistor R5 and the first capacitor C1 are connected in parallel between the first output end of the first optical coupler U1 and the third resistor R3, and the other ends of the fifth resistor R5 and the first capacitor C1 are grounded, and the second filtering unit includes a sixth resistor R6 and a second capacitor C2, one end of the sixth resistor R6 and the second capacitor C2 are connected in parallel between the first output end of the second optical coupler U2 and the fourth resistor R4, and the other ends of the sixth resistor R6 and the second capacitor C2 are grounded.

[0013] Optionally, the device further includes a device function test bench, and the signal acquisition module, the signal conversion module, the phase sequence detection module and the power supply module are all built into the device function test bench.

[0014] Optionally, the device further comprises a screen display module, wherein the screen display module is respectively connected to the signal acquisition module, the signal conversion module and the output end of the inversion detection chip, and the screen display module is connected to the power supply module.

[0015] Optionally, the output end of the phase detection chip is connected to the main control system of the equipment function test bench, and the main control system is connected to the screen display module.

[0016] Optionally, the signal conversion module includes a low-pass filter, an operational amplifier and an RC resonant circuit, the signal acquisition module is connected to the low-pass filter, the low-pass filter is connected to the operational amplifier, the operational amplifier is connected to the RC resonant circuit, and the RC resonant circuit is connected to the phase sequence detection module.

[0017] The beneficial effects of the utility model are:

[0018] The PWM drive signal of the device under test is collected by the signal acquisition module, and the PWM drive signal is input into the signal conversion module, and then the PWM drive signal is converted into a PWM sine-cosine waveform signal by the signal conversion module, and the PWM sine-cosine waveform signal is input into the phase sequence detection module, and finally the phase sequence detection of the device under test is completed after the phase sequence detection module receives the PWM sine-cosine waveform signal. Compared with the prior art, the phase sequence detection process in the utility model can avoid human operation, thereby avoiding detection errors caused by human operation and improving the accuracy and efficiency of phase sequence detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of a phase sequence detection device of a PWM control mode in the utility model.

[0020] Figure 2 It is a signal waveform diagram of the PWM sine-cosine waveform signal in the utility model.

[0021] Figure 3 It is a module schematic diagram of the phase sequence detection module in the utility model.

[0022] Description of reference numerals:

[0023] 1. Signal acquisition module; 2. Signal conversion module; 3. Phase sequence detection module; 4. Power supply module; 5. Screen display module; 6. Main control system; 31. Bypass unit; 32. Optocoupler unit; 33. Reverse phase detection unit; 34. First filter unit; 35. Second filter unit. DETAILED DESCRIPTION

[0024] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0025] The utility model discloses a phase sequence detection device of PWM control mode. Figure 1The phase sequence detection device of PWM control mode includes a signal acquisition module 1, a signal conversion module, a phase sequence detection module 3 and a power supply module 4. The signal acquisition module 1 is connected to the signal conversion module, the signal conversion module is connected to the phase sequence detection module 3, the power supply module 4 is respectively connected to the signal acquisition module 1, the signal conversion module and the phase sequence detection module 3, and the signal acquisition module 1 is connected to the three-phase terminal of the device under test through UVW three-phase wiring. The signal acquisition module 1 can be an STM32 single-chip microcomputer, and the signal acquisition module 1 is used to collect the PWM drive signal of the device under test and input the PWM drive signal to the signal conversion module.

[0026] The signal conversion module includes a low-pass filter, an operational amplifier and an RC resonant circuit. The signal acquisition module 1 is connected to the low-pass filter, the low-pass filter is connected to the operational amplifier, the operational amplifier is connected to the RC resonant circuit, and the RC resonant circuit is connected to the phase sequence detection module 3. The signal conversion module converts the PWM drive signal into a PWM sine-cosine waveform signal, and inputs the PWM sine-cosine waveform signal to the phase sequence detection module 3. Figure 2 , Figure 2 That is, the signal waveform of the PWM sine-cosine waveform signal output by the signal conversion module. The phase sequence detection module 3 is used to complete the phase sequence detection of the device under test after receiving the PWM sine-cosine waveform signal.

[0027] like Figure 1 As shown, the phase sequence detection device of the PWM control mode also includes a device function test bench and a screen display module 5. The signal acquisition module 1, the signal conversion module, the phase sequence detection module 3 and the power supply module 4 are all built in the device function test bench. The screen display module 5 is arranged on the surface of the device function test bench, and the screen display module 5 is powered by the power supply module 4. The device function test bench has a main control system 6, which is powered by the power supply module 4. The main control system 6 is also connected to the phase sequence detection module 3 to obtain the detection result of the phase sequence detection module 3. The main control system 6 can manage and record the device information and phase sequence detection result of each device to be tested. The main control system 6 is also connected to the screen display module 5, so that the data information recorded by the main control system 6 is displayed in the screen display module 5. The screen display module 5 is a comprehensive display integrated with components such as an oscilloscope and an electronic display screen. The screen display module 5 is connected to the signal acquisition module 1, the signal conversion module and the phase sequence detection module 3 respectively. The screen display module 5 can display the PWM driving signal waveform collected by the signal acquisition module 1 , the PWM sine-cosine waveform signal converted by the signal conversion module, and the phase sequence detection result output by the phase sequence detection module 3 .

[0028] Reference Figure 3The phase sequence detection module 3 includes a bypass unit 31, an optical coupling unit 32 and an anti-phase detection unit 33. The bypass unit 31 is connected to the output end of the signal conversion module, the optical coupling unit 32 is connected to the bypass unit 31, and the anti-phase detection unit 33 is connected to the optical coupling unit 32. The anti-phase detection unit 33 is used to output the phase sequence detection result. The bypass unit 31 includes a first resistor R1, a second resistor R2, a first diode D1, a second diode D2, a third diode D3 and a fourth diode D4. The optical coupling unit 32 includes a first optical coupler U1 and a second optical coupler U2. The first optical coupler U1 and the second optical coupler U2 each include two input ends and two output ends.

[0029] One end of the first resistor R1 is connected to the first output end of the signal conversion module, the other end of the first resistor R1 is connected to the cathode of the first diode D1, the anode of the first diode D1 is connected to the anode of the second diode D2 and the second input end of the first optical coupler U1, the cathode of the second diode D2 is connected to the second output end of the signal conversion module and the first input end of the first optical coupler U1, the first output end of the first optical coupler U1 is connected to the reverse phase detection unit 33, and the second output end of the first optical coupler U1 is connected to the power supply module 4. One end of the second resistor R2 is connected to the third output end of the signal conversion module, the other end of the second resistor R2 is connected to the cathode of the third diode D3, the anode of the third diode D3 is connected to the anode of the fourth diode D4 and the second input end of the second optical coupler U2, the cathode of the fourth diode D4 is connected to the second output end of the signal conversion module and the first input end of the second optical coupler U2, the first output end of the second optical coupler U2 is connected to the reverse phase detection unit 33, and the second output end of the second optical coupler U2 is connected to the power supply module 4.

[0030] The anti-phase detection unit 33 includes a third resistor R3, a fourth resistor R4, a first inverter A1, a second inverter A2 and an anti-phase detection chip, one end of the third resistor R3 is connected to the first output end of the first optical coupler U1, the other end of the third resistor R3 is connected to the input end of the first inverter A1, the output end of the first inverter A1 is connected to the first input end of the anti-phase detection chip, one end of the fourth resistor R4 is connected to the first output end of the second optical coupler U2, the other end of the fourth resistor R4 is connected to the input end of the second inverter A2, the output end of the second inverter A2 is connected to the second input end of the anti-phase detection chip, and the anti-phase detection chip outputs the phase sequence detection result through the output end. The anti-phase detection chip can adopt a MM32F3270-LQFP48 chip or a detection chip composed of a plurality of operational amplifiers and comparators.

[0031] like Figure 3As shown, the phase sequence detection module 3 also includes a first filter unit 34 and a second filter unit 35, the first filter unit 34 is connected between the first optical coupler U1 and the first inverter A1, and the second filter unit 35 is connected between the second optical coupler U2 and the second inverter A2. The first filter unit 34 includes a fifth resistor R5 and a first capacitor C1, one end of the fifth resistor R5 and the first capacitor C1 are both connected in parallel between the first output end of the first optical coupler U1 and the third resistor R3, and the other end of the fifth resistor R5 and the first capacitor C1 are both grounded, and the second filter unit 35 includes a sixth resistor R6 and a second capacitor C2, one end of the sixth resistor R6 and the second capacitor C2 are both connected in parallel between the first output end of the second optical coupler U2 and the fourth resistor R4, and the other end of the sixth resistor R6 and the second capacitor C2 are both grounded.

[0032] In one embodiment, if the anti-phase detection chip is a detection chip composed of multiple operational amplifiers and comparators, it specifically includes two groups of voltage followers and a voltage comparator, wherein each group of voltage followers includes an operational amplifier and a capacitor. The first optical coupler U1 outputs a signal through the first output end and outputs it to the input end of one group of voltage followers through the first filtering unit 34, and the second optical coupler U2 outputs a signal through the first output end and outputs it to the input end of another group of voltage followers through the second filtering unit 35. The output ends of the two groups of voltage followers are connected to the input end of the voltage comparator, and the voltage comparison result is output by the voltage comparator as the phase sequence detection result.

[0033] In another embodiment, if the anti-phase detection chip is a single-chip chip, it can be determined whether the signal output by the first optical coupler U1 through the first output terminal is a high level. If it is a high level, after a preset first delay time, it is determined whether the signal output by the second optical coupler U2 through the first output terminal is a low level. If it is a low level, it is determined that the phase sequence of the three-phase power supply is positive, otherwise the phase sequence of the three-phase power supply is incorrect. If the signal output by the first optical coupler U1 through the first output terminal is a low level, after a preset second delay time, it is determined whether the signal output by the second optical coupler U2 through the first output terminal is a low level. If it is a low level, the phase sequence of the three-phase power supply is positive, otherwise the phase sequence of the three-phase power supply is incorrect.

[0034] A person skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of protection of the present application is limited to these examples. In line with the concept of the present application, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of different aspects of one or more embodiments of the present application as described above, which are not provided in detail for the sake of simplicity.

[0035] One or more embodiments of the present application are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the present application. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of one or more embodiments of the present application should be included in the protection scope of the present application.

Claims

1. A phase sequence detection device of PWM control mode, characterized in that: The device includes a signal acquisition module, a signal conversion module, a phase sequence detection module and a power supply module. The signal acquisition module is connected to the signal conversion module, the signal conversion module is connected to the phase sequence detection module, the power supply module is connected to the signal acquisition module, the signal conversion module and the phase sequence detection module respectively, the signal acquisition module is connected to the three-phase terminal of the device under test through UVW three-phase wiring, the signal acquisition module is used to acquire the PWM drive signal of the device under test, and input the PWM drive signal to the signal conversion module, the signal conversion module converts the PWM drive signal into a PWM sine-cosine waveform signal, and inputs the PWM sine-cosine waveform signal into the phase sequence detection module, and the phase sequence detection module is used to complete the phase sequence detection of the device under test after receiving the PWM sine-cosine waveform signal.

2. The phase sequence detection device of PWM control method according to claim 1, characterized in that: The phase sequence detection module includes a bypass unit, an optical coupling unit and an anti-phase detection unit. The bypass unit is connected to the output end of the signal conversion module, the optical coupling unit is connected to the bypass unit, the anti-phase detection unit is connected to the optical coupling unit, and the anti-phase detection unit is used to output the phase sequence detection result.

3. The phase sequence detection device of PWM control method according to claim 2, characterized in that: The bypass unit includes a first resistor R1, a second resistor R2, a first diode D1, a second diode D2, a third diode D3 and a fourth diode D4, and the optical coupling unit includes a first optical coupler U1 and a second optical coupler U2, and the first optical coupler U1 and the second optical coupler U2 each include two input terminals and two output terminals; One end of the first resistor R1 is connected to the first output end of the signal conversion module, the other end of the first resistor R1 is connected to the cathode of the first diode D1, the anode of the first diode D1 is respectively connected to the anode of the second diode D2 and the second input end of the first optical coupler U1, the cathode of the second diode D2 is respectively connected to the second output end of the signal conversion module and the first input end of the first optical coupler U1, the first output end of the first optical coupler U1 is connected to the anti-phase detection unit, and the second output end of the first optical coupler U1 is connected to the power supply module; One end of the second resistor R2 is connected to the third output end of the signal conversion module, the other end of the second resistor R2 is connected to the cathode of the third diode D3, the anode of the third diode D3 is respectively connected to the anode of the fourth diode D4 and the second input end of the second optical coupler U2, the cathode of the fourth diode D4 is respectively connected to the second output end of the signal conversion module and the first input end of the second optical coupler U2, the first output end of the second optical coupler U2 is connected to the anti-phase detection unit, and the second output end of the second optical coupler U2 is connected to the power supply module.

4. The phase sequence detection device of PWM control method according to claim 3, characterized in that: The reverse phase detection unit includes a third resistor R3, a fourth resistor R4, a first inverter A1, a second inverter A2 and a reverse phase detection chip, one end of the third resistor R3 is connected to the first output end of the first optical coupler U1, the other end of the third resistor R3 is connected to the input end of the first inverter A1, the output end of the first inverter A1 is connected to the first input end of the reverse phase detection chip, one end of the fourth resistor R4 is connected to the first output end of the second optical coupler U2, the other end of the fourth resistor R4 is connected to the input end of the second inverter A2, the output end of the second inverter A2 is connected to the second input end of the reverse phase detection chip, and the reverse phase detection chip outputs the phase sequence detection result through the output end.

5. The phase sequence detection device of PWM control method according to claim 4, characterized in that: The phase sequence detection module further includes a first filtering unit and a second filtering unit. The first filtering unit is connected between the first optical coupler U1 and the first inverter A1, and the second filtering unit is connected between the second optical coupler U2 and the second inverter A2.

6. The phase sequence detection device of PWM control method according to claim 5, characterized in that: The first filtering unit includes a fifth resistor R5 and a first capacitor C1, one end of the fifth resistor R5 and the first capacitor C1 are connected in parallel between the first output end of the first optical coupler U1 and the third resistor R3, and the other ends of the fifth resistor R5 and the first capacitor C1 are grounded. The second filtering unit includes a sixth resistor R6 and a second capacitor C2, one end of the sixth resistor R6 and the second capacitor C2 are connected in parallel between the first output end of the second optical coupler U2 and the fourth resistor R4, and the other ends of the sixth resistor R6 and the second capacitor C2 are grounded.

7. The phase sequence detection device of PWM control method according to claim 4, characterized in that: The device also includes an equipment function test bench, and the signal acquisition module, the signal conversion module, the phase sequence detection module and the power supply module are all built in the equipment function test bench.

8. The phase sequence detection device of PWM control method according to claim 7, characterized in that: The device further comprises a screen display module, which is respectively connected to the signal acquisition module, the signal conversion module and the output end of the anti-phase detection chip, and is connected to the power supply module.

9. The phase sequence detection device of PWM control method according to claim 8, characterized in that: The output end of the phase detection chip is connected to the main control system of the equipment function test bench, and the main control system is connected to the screen display module.

10. The phase sequence detection device of PWM control method according to claim 1, characterized in that: The signal conversion module includes a low-pass filter, an operational amplifier and an RC resonant circuit. The signal acquisition module is connected to the low-pass filter, the low-pass filter is connected to the operational amplifier, the operational amplifier is connected to the RC resonant circuit, and the RC resonant circuit is connected to the phase sequence detection module.

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