CN218824520U

CN218824520U - Rotary transformation signal generation device for testing new energy automobile inverter

Info

Publication number: CN218824520U
Application number: CN202222999081.3U
Authority: CN
Inventors: 陆宝石
Original assignee: Shenzhen Ti Intelligent Technology Suzhou Co ltd
Current assignee: Shenzhen Ti Intelligent Technology Suzhou Co ltd
Priority date: 2022-11-11
Filing date: 2022-11-11
Publication date: 2023-04-07
Anticipated expiration: 2032-11-11

Abstract

The utility model provides a become signal generation device soon for new energy automobile dc-to-ac converter test, including signal generation circuit, sinusoidal way and cosine circuit be connected with signal generation circuit respectively, sinusoidal way includes the first amplifier that input and the first output of signal generation circuit are connected, the first modulation circuit that first input and first amplifier output are connected, the sinusoidal excitation signal of being connected with first modulation circuit second input, the first single-ended poor circuit of commentaries on classics of being connected with first modulation circuit output, the cosine circuit includes that the input moves the looks ware 90 of being connected with signal generation circuit second output, move the second amplifier of looks ware output connection with 90, the second modulation circuit of being connected of first input and second amplifier output, the second single-ended poor circuit of revolving of being connected with second modulation circuit output. The utility model discloses need not PLC and outside servo motor and can generate high-quality sine and cosine signal, occupation space is little, and the cost is lower.

Description

Rotary transformation signal generation device for testing new energy automobile inverter

Technical Field

The utility model relates to a become signal generation device soon for new energy automobile dc-to-ac converter test.

Background

A rotation sensor, also called a resolver, is a sensor for measuring angular displacement and angular velocity of a rotating shaft of a rotating object. In the aging test process of the new energy automobile inverter, a real motor is generally not used as a load, and a reactor is used. In order to make the inverter work normally, a rotation sensor must be used to simulate the rotation speed signal of the real motor. In the prior art, a rotary transformer signal simulates the position state of an automobile at rest and different rotating speeds by driving a rotary transformer sensor through an external servo motor in a linkage manner. However, the conventional motor rotation method has the following two disadvantages: 1. the quality of sine and cosine signals is easily influenced by mechanical positioning, manufacturing process variation and the like, and stable and high-precision sine and cosine signals cannot be output. 2. Additional motor control programs, hardware such as a PLC and the like need to be added, the space occupation is large, and the cost is high.

SUMMERY OF THE UTILITY MODEL

The utility model provides a become signal generation device soon for new energy automobile dc-to-ac converter test need not PLC and outside servo motor can generate high-quality sine and cosine signal, and occupation space is little, and the cost is lower.

The utility model discloses a following technical scheme realizes:

a rotary variable signal generating device for testing a new energy automobile inverter comprises a signal generating circuit, a sine circuit and a cosine circuit, wherein the sine circuit and the cosine circuit are respectively connected with the signal generating circuit, the sine circuit comprises a first amplifier, a first modulation circuit, a sine exciting signal, a first single-end to differential circuit and a second single-end to differential circuit, the input end of the first amplifier is connected with the first output end of the signal generating circuit, the first modulation circuit is connected with the output end of the first modulation circuit, the first single-end to differential circuit outputs a rotary sine signal, the cosine circuit comprises a 90-degree phase shifter, the input end of the 90-degree phase shifter is connected with the second output end of the signal generating circuit, the second amplifier is connected with the output end of the 90-degree phase shifter, the first input end of the second modulation circuit is connected with the output end of the second amplifier, the second single-end to differential circuit is connected with the output end of the second modulation circuit, the sine exciting signal is connected with the second input end of the second modulation circuit, the second single-end to differential circuit outputs a rotary cosine signal, and the first amplifier and the second amplifier are both programmable gain amplifiers.

Furthermore, the signal generating circuit comprises an MCU, a current generator with an input end connected with the output end of the MCU, and an I/V conversion circuit connected with the output end of the current generator, wherein the I/V conversion circuit outputs a voltage signal corresponding to the current signal generated by the current generator.

Further, the current generator is a DDS chip with model AD 9834.

Furthermore, the I/V conversion circuit includes two pull-down resistors respectively connected in series with two output terminals of the DDS chip, one end of each of the two pull-down resistors is grounded, and the other end of each of the two pull-down resistors is respectively used as a first output terminal and a second output terminal of the signal generation circuit.

Further, the first modulation circuit and the second modulation circuit each include an analog multiplier.

Further, the sinusoidal excitation signal is a sinusoidal fundamental frequency signal.

The utility model discloses following beneficial effect has:

the utility model discloses a signal generator generates sinusoidal signal according to the demand, this sinusoidal signal is all the way through first amplifier and with sinusoidal excitation signal modulation back again obtain the rotary change sinusoidal signal through first single-ended commentaries on classics differential circuit, another way of sinusoidal signal that signal generator generated becomes the cosine signal with same frequency and amplitude through 90 phase shift circuit, this cosine signal obtains the rotary change cosine signal through the second single-ended commentaries on classics differential circuit again after second amplifier and with sinusoidal excitation signal modulation, so realized producing the rotary change signal through pure circuit promptly, need not PLC and servo motor in the circuit, the rotary change signal high quality and the temperature of production, also need not any machining part, the rotary change signal quality can not receive mechanical positioning influence, shared space has also been reduced, prior art scheme needs 450mm 600mm space, and the utility model discloses only need 150mm 1.6mm space, the cost is still reduced simultaneously, the utility model discloses the cost is only for prior art about 30%.

Drawings

The present invention will be described in further detail with reference to the accompanying drawings.

Fig. 1 is a schematic block diagram of the present invention.

Fig. 2 is a circuit diagram of the signal generating circuit of the present invention.

Fig. 3 is an internal circuit diagram of the programmable gain amplifier of the present invention.

Fig. 4 is a circuit diagram of the 90 ° phase shifter of the present invention.

Wherein, 1, a signal generating circuit; 11. MCU; 12. a current generator; 13. an I/V conversion circuit; 2. a sine path; 21. a first amplifier; 22. a first modulation circuit; 23. a first single-ended to differential circuit; 3. a cosine path; 31. a 90 DEG phase shifter; 32. a second amplifier; 33. a second modulation circuit; 34. a second single-ended to differential circuit.

Detailed Description

As shown in fig. 1, the resolver signal generating device for testing the new energy automobile inverter includes a signal generating circuit 1, a sine circuit 2 and a cosine circuit 3 respectively connected to the signal generating circuit 1, where the sine circuit 2 includes a first amplifier 21 whose input end is connected to a first output end of the signal generating circuit 1, a first modulation circuit 22 whose first input end is connected to an output end of the first amplifier 21, a sine excitation signal connected to a second input end of the first modulation circuit 22, and a first single-ended differential conversion circuit 23 connected to an output end of the first modulation circuit 22, where the first single-ended differential conversion circuit 23 outputs a rotational sine signal (SIN +, SIN-), the cosine circuit 3 includes a 90 ° phase shifter 31 whose input end is connected to a second output end of the signal generating circuit 1, a second amplifier 32 connected to an output end of the 90 ° phase shifter 31, a second modulation circuit 33 whose first input end is connected to an output end of the second amplifier 32, and a second differential conversion circuit connected to an output end of the second modulation circuit 33, where the sine excitation signal is connected to a second input end of the second modulation circuit 33, and the second single-ended differential conversion circuit outputs a COS rotational signal (COS +, COS rotational signal).

The signal generating circuit 1 includes an MCU11, a current generator 12 having an input terminal connected to an output terminal of the MCU11, and an I/V conversion circuit 13 connected to an output terminal of the current generator 12, wherein the I/V conversion circuit 13 outputs a voltage signal corresponding to a current signal generated by the current generator 12, and a specific circuit of the signal generating circuit 1 is shown in fig. 2. The first amplifier 21 and the second amplifier 32 are both Programmable Gain Amplifiers (PGA), and the selectable gains of the programmable gain amplifiers are 1,2,4,8 \8230 \ 128 times, which can respectively provide 1 × vcal,0.9 × vcal,0.1 × vcal and reference voltage input Vref calibration for the internal ADC of the DDS chip, thus greatly eliminating the gain error and gain error of the ADC and improving the signal accuracy. The internal circuitry of the programmable gain amplifier is shown in fig. 3.

In the present embodiment, the current generator 12 is a DDS chip with model AD 9834. The waveform output generated by the DAC in the DDS chip is complementary current output, so that the I/V conversion circuit 13 is required to convert the waveform output into a voltage signal. The I/V conversion circuit 13 includes two pull-down resistors R respectively connected in series with the two output terminals of the DDS chip, one end of each of the two pull-down resistors R is grounded, and the other end of each of the two pull-down resistors R is respectively used as a first output terminal and a second output terminal of the signal generation circuit 1. In this embodiment, the two pull-down resistors R have a resistance of 200 Ω.

The AD9834 chip can realize the following functions: the frequency output can be selected finely, the frequency selection from low to high is realized, the frequency minimum resolution is 0.279Hz, sine waves with the frequency step size of 0.279Hz and 37.5MHz from 0.279Hz can be emitted; the frequency hopping can be carried out quickly, and the phase continuity can be ensured, which is difficult to realize in the traditional analog signal generator; an initial phase setting can be achieved.

The resolver sensor has a pair of cosine differential signals in addition to a pair of sine differential signals. The sine signal generated by the DDS needs to be phase shifted by 90 ° to become a cosine signal, and fig. 4 shows the internal circuit of the 90 ° phase shifter 31. In an electronic circuit, at the moment of electrifying a capacitor, the circuit charges the capacitor, the current which is charged at the beginning is the maximum value, the voltage approaches 0, the current is gradually reduced along with the continuous increase of the electric charge quantity at two ends of the capacitor, and the voltage is gradually increased until the charging of the capacitor is finished. At this time, the voltage at the two ends of the capacitor is the maximum value, the charging current of the capacitor is the minimum value, and in fig. 4, the terminal voltage of the capacitor C6 is taken as the output VOUT, so that a signal with a phase shifted by 90 ° can be obtained.

In the present embodiment, the first modulation circuit 22 and the second modulation circuit 33 each include an analog multiplier. An analog multiplier is an existing integrated circuit. The sine signal of the sine path 2 and the cosine signal of the cosine path 3 are multiplied by externally input base frequency signals (EXC _ P and EXC _ N) through analog multipliers respectively, so that the modulation of the signals is realized.

The above description is only a preferred embodiment of the present invention, and therefore the scope of the present invention should not be limited thereby, and all equivalent changes and modifications made within the scope of the claims and the specification should be considered within the scope of the present invention.

Claims

1. The utility model provides a become signal generating device soon for new energy automobile inverter test which characterized in that: the sine circuit comprises a first amplifier with an input end connected with a first output end of the signal generating circuit, a first modulation circuit with a first input end connected with an output end of the first amplifier, a sine excitation signal connected with a second input end of the first modulation circuit, and a first single-end differential-to-differential circuit connected with an output end of the first modulation circuit, wherein the first single-end differential-to-differential circuit outputs a rotating sine signal, the cosine circuit comprises a 90-degree phase shifter with an input end connected with a second output end of the signal generating circuit, a second amplifier connected with an output end of the 90-degree phase shifter, a second modulation circuit with a first input end connected with an output end of the second amplifier, and a second single-end differential-to-differential circuit connected with an output end of the second modulation circuit, the sine excitation signal is connected with a second input end of the second modulation circuit, the second single-end differential-to-differential circuit outputs a rotating cosine signal, and the first amplifier and the second amplifier are both programmable gain amplifiers.

2. The resolver signal generating device for testing the new energy automobile inverter according to claim 1, wherein: the signal generating circuit comprises an MCU, a current generator with an input end connected with the output end of the MCU, and an I/V conversion circuit connected with the output end of the current generator, wherein the I/V conversion circuit outputs a voltage signal corresponding to a current signal generated by the current generator.

3. The resolver signal generating device for testing the new energy automobile inverter according to claim 2, wherein: the current generator is a DDS chip with the model number of AD 9834.

4. The resolver signal generating device for testing the new energy automobile inverter according to claim 3, wherein the resolver signal generating device comprises: the I/V conversion circuit comprises two pull-down resistors which are respectively connected with the two output ends of the DDS chip in series, one ends of the two pull-down resistors are grounded, and the other ends of the two pull-down resistors are respectively used as a first output end and a second output end of the signal generation circuit.

5. The resolver signal generating device for testing the new energy automobile inverter according to claim 1,2, 3 or 4, wherein: the first modulation circuit and the second modulation circuit each include an analog multiplier.

6. The rotation signal generating device for the inverter test of the new energy automobile according to claim 1,2, 3 or 4, characterized in that: the sine excitation signal is a sine fundamental frequency signal.