Rotary transformer simulation device

Abstract

The utility model provides a rotary transformer simulation device, which is applied to the technical field of motor testing, and comprises a main controller and an input signal conditioning module, the input end of the main controller is connected with a first input signal, and the output end of the main controller outputs a first output signal through a first output signal module; outputting a second output signal through a second output signal module; the first output signal module comprises a digital-to-analog converter I and an output signal conditioning module I, and the second output signal module comprises a digital-to-analog converter II and an output signal conditioning module II; the input signal conditioning module receives a second input signal and then processes the second input signal, the processed signal is respectively transmitted to the main controller, the digital-to-analog converter I and the digital-to-analog converter II, and the second input signal is an excitation signal EXC output by the motor control driving unit. The device is small in size, light in weight and low in cost, can be suitable for a large-scale production environment, does not have the problems of mechanical wear, aging and the like, and is relatively low in maintenance cost.

Description

Technical Field

[0001] The utility model belongs to the technical field of motor testing, and in particular relates to a rotary transformer simulation device. Background Art

[0002] The production test of the motor control drive unit of new energy vehicles requires the test equipment to be able to output the corresponding resolver signal. The resolver has high reliability and sufficiently high accuracy, and is widely used in the new energy industry for sampling the angle and speed of permanent magnet motors.

[0003] The rotary transformer, also known as the synchronous resolver, is an electromagnetic sensor. Figure 1 As shown in the figure, it consists of a stator and a rotor. The stator winding is the primary side of the transformer and receives the excitation voltage; the rotor winding is the secondary side of the transformer and obtains the induced voltage through electromagnetic coupling. The input signal and output signal of the rotary transformer are as follows: Figure 2 As shown, the input signal of the resolver is the excitation signal, and the output signal of the resolver is two sinusoidal modulation signals, which are a high-frequency carrier signal (generally 10kHz) and a low-frequency envelope signal that changes with the motor speed. The phase difference between the two signals is 90°.

[0004] In traditional test equipment, there are two ways to generate or simulate resolver signals:

[0005] A purely mechanical method is to use a motor to drive the transmission mechanism to rotate the resolver rotor to achieve true output of the resolver signal. In this method, the overall equipment is large in size, and the mechanical mechanism is prone to wear and aging. In some long-term uninterrupted test projects such as aging tests, the test equipment itself has a high failure rate and a relatively high maintenance cost.

[0006] Another method is to use a standard desktop waveform generator to generate two phase-locked orthogonal signals, and then use an analog multiplication device to multiply the excitation signal output by the motor controller with the two orthogonal signals, and finally realize the two-way modulation signal output of the simulated rotary transformer. This method can simulate the rotary transformer signal well, but the standard desktop signal generator is large and expensive, and the analog multiplication device is also relatively expensive. This solution is not the preferred solution for large-scale production testing. Utility Model Content

[0007] In view of the above problems in the prior art, the purpose of the utility model is to provide a rotating transformer simulation device which is small in size, light in weight, low in cost, suitable for large-scale production environments, free from problems such as mechanical wear and aging, and has low maintenance costs.

[0008] A rotary transformer simulation device comprises a main controller and an input signal conditioning module, wherein the input end of the main controller is connected to a first input signal, and the output end of the main controller outputs a first output signal through a first output signal module, and outputs a second output signal through a second output signal module; the first output signal module comprises a digital-to-analog converter 1 and an output signal conditioning module 1, and the second output signal module comprises a digital-to-analog converter 2 and an output signal conditioning module 2; the input signal conditioning module processes the second input signal after being connected to the second input signal, and transmits the processed signal to the main controller, the digital-to-analog converter 1, and the digital-to-analog converter 2 respectively, and the second input signal is an excitation signal EXC output by a motor control drive unit.

[0009] Preferably, the main controller includes an analog-to-digital conversion unit, a CAN communication interface and an SPI communication interface. The analog-to-digital conversion unit of the main controller is connected to the output end of the input signal conditioning module, and the analog-to-digital conversion unit is used to sample the excitation signal EXC and detect whether the excitation signal EXC is abnormal; the CAN communication interface of the main controller is connected to a CAN transceiver, and the CAN transceiver is connected to a host computer PC through a CAN bus. The host computer PC transmits a first input signal to the main controller, and the first input signal is a control signal; the SPI communication interface of the main controller includes a first interface SPI 1 and a second interface SPI2, the first interface SPI 1 is connected to digital-to-analog converter one, and the second interface SPI2 is connected to digital-to-analog converter two.

[0010] Preferably, the first digital-to-analog converter and the second digital-to-analog converter are both 12-bit current-type output multiplication digital-to-analog converters with an R-2R architecture.

[0011] Preferably, the input signal conditioning module is used to convert the excitation signal EXC output by the motor control drive unit into a single-ended signal, and scale the single-ended signal to a signal processing range of the analog-to-digital conversion unit of the main controller.

[0012] Preferably, the first excitation signal EXC+ and the second excitation signal EXC- output by the motor control drive unit are respectively transmitted to the first amplifier and the second amplifier through the filtering unit, the output ends of the first amplifier and the second amplifier are input to the input end of the third amplifier, and the output end of the third amplifier transmits a single-ended signal to the analog-to-digital conversion unit of the main controller.

[0013] Preferably, the output signal conditioning module 1 is used to convert the current output by the digital-to-analog converter 1 into a voltage, and output a first output signal after low-pass filtering and proportional amplification processing, and the first output signal is a sinusoidal signal SIN.

[0014] Preferably, the output signal conditioning module 2 is used to convert the current output by the digital-to-analog converter 2 into a voltage, and output a second output signal after low-pass filtering and proportional amplification processing, wherein the second output signal is a cosine signal COS.

[0015] Preferably, the information parameters carried by the first input signal include pole pair number, rotation speed, transformation ratio and rotation direction.

[0016] Preferably, the main controller is an MCU, and the MCU generates a digital waveform by means of distributed real-time communication.

[0017] The beneficial effects of the utility model are as follows: the rotary transformer simulation device adopts electronic components to realize the simulation of the rotary transformer signal, which is mainly realized through the main controller and the digital-to-analog converter 1 and the digital-to-analog converter 2. The core hardware structure is simple. After the configuration of the simulation device is completed, external command intervention is no longer required, and accurate sine signals and cosine signals with stable output can be generated.

[0018] Compared with the method of generating a resolver signal by rotating the resolver rotor through a transmission mechanism, simulating the resolver signal through electronic components can significantly reduce the size and weight of the overall equipment, and there is no problem of mechanical wear and aging. It has high reliability and low maintenance costs.

[0019] Compared with the method of generating a rotary transformer signal through a waveform generator, the electronic components of the simulation device can be integrated on a PCB board, which has a higher degree of integration, a smaller size, and a lower cost, and can be applied to a large-scale production environment.

[0020] In addition, the digital-to-analog converter not only realizes the quantization of digital signals, but also completes the signal multiplication and modulation function, eliminating the need to use additional hardware multiplication devices and lowering production costs.

[0021] With fault detection function, MCU samples the excitation signal EXC in real time through the analog-to-digital conversion unit to determine whether the excitation signal EXC is abnormal, which can make the test results more detailed and accurate, and facilitate the fault location of the tested product. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0023] Figure 1 It is the schematic diagram of the existing rotary transformer;

[0024] Figure 2 It is a waveform diagram of the input signal and output signal of the existing rotary transformer;

[0025] Figure 3 It is a principle block diagram of the utility model;

[0026] Figure 4 It is a connection diagram of the application scenario of the utility model;

[0027] Figure 5 It is a circuit diagram of the input signal conditioning module of the utility model;

[0028] Figure 6 It is a circuit diagram of the main controller of the utility model;

[0029] Figure 7 is a circuit diagram of the first output signal module of the utility model;

[0030] Figure 8 is a circuit diagram of the second output signal module of the utility model;

[0031] Fig. 9 It is a circuit diagram of a CAN transceiver of the utility model. DETAILED DESCRIPTION

[0032] Embodiment 1

[0033] like Figure 3 , Figure 4 As shown, a rotary transformer simulation device includes a main controller, an input signal conditioning module, a first output signal module and a second output signal module. The input end of the main controller is connected to the first input signal, and the output end of the main controller outputs the first output signal through the first output signal module and outputs the second output signal through the second output signal module. The input signal conditioning module processes the second input signal after being connected to the second input signal, and transmits the processed signal to the main controller, the first digital-to-analog converter, and the second digital-to-analog converter respectively. The second input signal is the excitation signal EXC output by the motor control drive unit.

[0034] like Figure 7 , Figure 8 As shown, specifically, the first output signal module includes a digital-to-analog converter 1 and an output signal conditioning module 1, and the second output signal module includes a digital-to-analog converter 2 and an output signal conditioning module 2. Wherein, the digital-to-analog converter 1 and the digital-to-analog converter 2 are both 12-bit current-type output multiplication digital-to-analog converters with an R-2R architecture, and the digital-to-analog converter model selected in this embodiment is AD5452.

[0035] The output signal conditioning module 1 is used to convert the current output by the digital-to-analog converter 1 into a voltage, and output a first output signal after low-pass filtering and proportional amplification processing. The first output signal is a sinusoidal signal SIN.

[0036] The output signal conditioning module 2 is used to convert the current output by the digital-to-analog converter 2 into a voltage, and output a second output signal after low-pass filtering and proportional amplification processing. The second output signal is a cosine signal COS.

[0037] In addition, if Figure 6 As shown, the main controller is an MCU, and the model of the MCU in this embodiment is STM32G474, and the MCU generates a digital waveform by distributed real-time communication. Among them, the main controller includes an analog-to-digital conversion unit, a CAN communication interface, and an SPI communication interface. The analog-to-digital conversion unit of the main controller is connected to the output end of the input signal conditioning module, and the analog-to-digital conversion unit is used to sample the excitation signal EXC and detect whether the excitation signal EXC is abnormal.

[0038] like Fig. 9 As shown, the CAN communication interface of the main controller is connected to the CAN transceiver, and the CAN transceiver is connected to the host computer PC through the CAN bus. The host computer PC transmits a first input signal to the main controller. The first input signal is a control signal. The information parameters carried by the first input signal include the number of pole pairs, rotation speed, transformation ratio and rotation direction, which are used to control the working state of the rotary transformer simulation device. The model of the CAN transceiver is MCP2558FD.

[0039] The SPI communication interface of the main controller includes a first interface SPI1 and a second interface SPI2. The first interface SPI1 is connected to a first digital-to-analog converter, and the second interface SPI2 is connected to a second digital-to-analog converter.

[0040] like Figure 5 As shown, specifically, the input signal conditioning module is used to convert the excitation signal EXC output by the motor control drive unit into a single-ended signal, and scale the single-ended signal to the signal processing range of the analog-to-digital conversion unit of the main controller. The input signal conditioning module includes a first amplifier, a second amplifier and a third amplifier. The first excitation signal EXC+ and the second excitation signal EXC- output by the motor control drive unit are respectively transmitted to the first amplifier and the second amplifier through the filtering unit. The output ends of the first amplifier and the second amplifier are input to the input end of the third amplifier, and the output end of the third amplifier transmits a single-ended signal to the analog-to-digital conversion unit of the main controller.

[0041] When the resolver simulation device is used, the excitation signal EXC, the sine signal SIN, and the cosine signal COS are respectively connected to the signal interfaces corresponding to the motor control drive unit to be tested, wherein the frequency of the excitation signal EXC is generally around 10KHz, and the sine signal SIN and the cosine signal COS are two-way modulation signals with the excitation signal EXC as the carrier, which contain the angular displacement and angular velocity information of the resolver.

[0042] Working principle: When the rotary transformer simulation device is in use, the host computer PC sends the relevant parameter information such as the number of pole pairs, rotation speed, transformation ratio and rotation direction required for the rotary transformer signal simulation to the MCU through the CAN bus. After receiving and parsing the instructions, the MCU generates configuration parameters, which include the sampling rate of the analog-to-digital conversion unit and the digital-to-analog converter, the sine signal wave table, the cosine signal wave table, etc.; then the MCU starts the analog-to-digital conversion unit for sampling to detect whether the excitation signal EXC is abnormal. If the excitation signal EXC is normal, the sine signal wave table and the cosine signal wave table data are sent to the digital-to-analog converter 1 and the digital-to-analog converter 2 through the SPI communication interface respectively; the digital-to-analog converter 1 and the digital-to-analog converter 2 then multiply the quantized signal of the wave table with the excitation signal EXC to obtain the final first output signal and second output signal, namely the sine signal SIN and the cosine signal COS.

[0043] Specifically, the MCU generates a set of sine signal wave tables and a set of cosine signal wave tables respectively through software DDS; the MCU sends the data of the sine signal wave table to the digital-to-analog converter 1 through the first interface SPI 1, and the digital-to-analog converter 1 internally quantizes to obtain signal 1 U1; the MCU also sends the data of the cosine signal wave table to the digital-to-analog converter 2 through the second interface SPI2, and the digital-to-analog converter 2 internally quantizes to obtain signal 2 U2.

[0044] The signal output by the input signal conditioning module is recorded as the processed signal U EXC , DAC 1 and DAC 2 have functions similar to analog multipliers. DAC 1 will convert signal 1 U1 and U EXC Multiply to get the conversion signal -U DAC1 And output, the digital-to-analog converter 2 will convert the signal U2 and U EXC Multiply to get the conversion signal U DAC2 And output, finally, the conversion signal U DAC1 After being processed by the output signal conditioning module 1, a sinusoidal signal SIN is generated and output, and the conversion signal U DAC2 After being processed by the output signal conditioning module 2, a cosine signal COS is generated and output.

[0045] The above description is only a preferred embodiment of the utility model and is not intended to limit the utility model. Although the utility model is described in detail with reference to the above embodiments, those skilled in the art can still modify the technical solutions recorded in the above embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A rotary transformer simulation device, characterized in that: It includes a main controller and an input signal conditioning module, wherein the input end of the main controller is connected to a first input signal, and the output end of the main controller outputs a first output signal through a first output signal module and outputs a second output signal through a second output signal module; The first output signal module includes a digital-to-analog converter 1 and an output signal conditioning module 1, and the second output signal module includes a digital-to-analog converter 2 and an output signal conditioning module 2; The input signal conditioning module processes the second input signal after receiving it, and transmits the processed signal to the main controller, the first digital-to-analog converter, and the second digital-to-analog converter respectively. The second input signal is the excitation signal EXC output by the motor control drive unit.

2. The rotary transformer simulation device according to claim 1, characterized in that: The main controller includes an analog-to-digital conversion unit, a CAN communication interface and an SPI communication interface. The analog-to-digital conversion unit of the main controller is connected to the output end of the input signal conditioning module. The analog-to-digital conversion unit is used to sample the excitation signal EXC and detect whether the excitation signal EXC is abnormal. The CAN communication interface of the main controller is connected to a CAN transceiver, the CAN transceiver is connected to a host computer PC via a CAN bus, and the host computer PC transmits a first input signal to the main controller, wherein the first input signal is a control signal; The SPI communication interface of the main controller includes a first interface SPI1 and a second interface SPI2. The first interface SPI1 is connected to a first digital-to-analog converter, and the second interface SPI2 is connected to a second digital-to-analog converter.

3. The rotary transformer simulation device according to claim 2, characterized in that: The first digital-to-analog converter and the second digital-to-analog converter are both 12-bit current-type output multiplication digital-to-analog converters with an R-2R architecture.

4. The rotary transformer simulation device according to claim 2, characterized in that: The input signal conditioning module is used to convert the excitation signal EXC output by the motor control drive unit into a single-ended signal, and scale the single-ended signal to a signal processing range of the analog-to-digital conversion unit of the main controller.

5. The rotary transformer simulation device according to claim 4, characterized in that: The first excitation signal EXC+ and the second excitation signal EXC- output by the motor control drive unit are respectively transmitted to the first amplifier and the second amplifier through the filtering unit, the output ends of the first amplifier and the second amplifier are input to the input end of the third amplifier, and the output end of the third amplifier transmits a single-ended signal to the analog-to-digital conversion unit of the main controller.

6. The rotary transformer simulation device according to claim 1, characterized in that: The output signal conditioning module 1 is used to convert the current output by the digital-to-analog converter 1 into a voltage, and output a first output signal after low-pass filtering and proportional amplification processing, wherein the first output signal is a sinusoidal signal SIN.

7. The rotary transformer simulation device according to claim 1, characterized in that: The output signal conditioning module 2 is used to convert the current output by the digital-to-analog converter 2 into a voltage, and output a second output signal after low-pass filtering and proportional amplification, wherein the second output signal is a cosine signal COS.

8. The rotary transformer simulation device according to claim 1, characterized in that: The information parameters carried by the first input signal include the number of pole pairs, rotation speed, transformation ratio and rotation direction.

9. The rotary transformer simulation device according to claim 1, characterized in that: The main controller is an MCU, and the MCU generates a digital waveform by means of distributed real-time communication.

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