CN209029928U - An energy feedback device in a converter load test - Google Patents

Abstract

The utility model proposes an energy feedback device in a load test of a converter, comprising: a full-bridge inverter module, a full-bridge drive module, a first LC filter module, a transformer isolation module, a full-bridge rectifier module, and a second LC filter module Module, Boost boost module, control module, keyboard module, voltage transformer module, voltage signal preprocessing module, current transformer module, current signal preprocessing module, AD sampling module, optocoupler isolation module. The full-bridge inverter module, the full-bridge drive module and the first LC filter module complete the DC-AC conversion function; the full-bridge rectifier module, the second LC filter module and the Boost boost module jointly complete the AC-DC conversion function, the conversion output is fed back to the front end of the full-bridge inverter module to achieve energy feedback. The utility model has the advantages that the stable sinusoidal alternating current can be output, the energy feedback is realized, the system is stable, and the precision is high.

Description

An energy feedback device in a converter load test

technical field

The utility model belongs to the field of power supplies, in particular to an energy feedback device in a load test of a converter.

Background technique

The energy feedback device in the load test of the converter is a device that returns energy to the input end and supplies power to the rear stage together with the DC power supply, thereby achieving the purpose of saving energy. The energy feedback device in the load test has a very wide range of applications, and is widely used in various load tests of various converters, power supply aging tests and other tests that require loads. With the development of the electronics industry in recent years, a large number of converters, power supplies and other devices need to be tested under load, and direct testing will waste a lot of electrical energy. If the power wasted in these tests could be recovered, it would save a lot of energy. Therefore, the energy feedback device in the load test is a device that is very much needed in the market.

Nowadays, the energy feedback device on the market is still in the developing state. Most load tests still consume a lot of electric energy. An energy feedback device with controllable feedback voltage, high efficiency, high precision, high system stability and good human-computer interaction is urgently needed. .

Utility model content

The purpose of the utility model is to realize the energy feedback in the load experiment of the converter and effectively reduce the energy loss of the load experiment, but the application range of the energy feedback device is not limited to the load experiment.

In order to achieve the above purpose, the technical solution adopted by the present invention is: an energy feedback device in a load test of a converter, comprising: a full-bridge inverter module, a full-bridge drive module, a first LC filter module, a transformer isolation module, Full-bridge rectifier module, second LC filter module, boost boost module, control module, keyboard module, voltage transformer module, voltage signal preprocessing module, current transformer module, current signal preprocessing module, AD sampling module, optocoupler Isolated module.

The full-bridge inverter module, the first LC filter module, the transformer isolation module, the full-bridge rectifier module, the second LC filter module, and the Boost boosting module are sequentially connected in series through wires; the full-bridge inverter module and the The boost boosting module is connected by wires; the full-bridge inverter module is connected with the full-bridge drive module by wires; the full-bridge drive module is connected with the optocoupler isolation module; the boost booster module is connected with the optocoupler The isolation module is connected; the first LC filter module is respectively connected with the voltage transformer module and the current transformer module through wires in sequence; the voltage signal preprocessing module is connected with the voltage transformer module; the current signal The preprocessing module is connected with the current transformer module; the AD sampling module is respectively connected with the voltage signal preprocessing module and the current signal preprocessing module through wires in sequence; the control module is respectively connected with the AD sampling module , the optocoupler isolation module and the keyboard module are connected in turn by wires.

Preferably, the full-bridge inverter module, the full-bridge drive module and the first LC filter module complete the DC-AC conversion function; the full-bridge rectifier module, the second LC filter module and the Boost boost module jointly complete the AC conversion function -DC conversion function, the conversion output is fed back to the front end of the full-bridge inverter module to achieve energy feedback;

Preferably, the full-bridge inverter module inverts the DC signal into an AC signal according to the driving signal.

Preferably, the full-bridge driving module generates the driving signal according to the isolated sinusoidal pulse modulation signal.

Preferably, the first LC filter module is used to filter the AC signal and output the filtered sinusoidal AC signal.

Preferably, the transformer isolation module is used to obtain the isolated sinusoidal AC signal from the filtered sinusoidal AC signal through AC step-down and AC boost, and is composed of a 220V/48V step-down transformer and a 48V/220V step-up transformer. The 220V The /48V step-down transformer is used for AC step-down, and the 48V/220V step-up transformer is used for AC step-up.

Preferably, the full-bridge rectifier module is used to rectify the isolated sinusoidal AC signal to obtain a rectified DC signal.

Preferably, the second LC filter module is used to filter the rectified DC signal and output the filtered DC signal;

Preferably, the boost module boosts the voltage of the filtered DC signal according to the isolated pulse signal, and feeds back the DC signal after the voltage boost to the full-bridge inverter module to achieve energy return.

Preferably, the voltage transformer module is used to convert the AC strong voltage signal into a voltage acquisition signal.

Preferably, the current transformer module is used to convert the AC strong current signal into the current acquisition signal.

Preferably, the voltage signal preprocessing module is used for filtering and preprocessing the voltage acquisition signal to obtain the analog voltage signal.

Preferably, the current signal preprocessing module is used for filtering and preprocessing the current acquisition signal to obtain the analog current signal.

Preferably, the AD sampling module is configured to convert an analog voltage signal into a digital voltage signal, convert an analog current signal into a digital current signal, and transmit the digital voltage signal and the digital current signal to the control module.

Preferably, the keyboard module is used to set the signal frequency, voltage amplitude, and current amplitude to meet different power supply requirements of loads, and is a matrix keyboard.

Preferably, the control module is configured to generate a sinusoidal pulse modulation signal and a pulse signal according to the digital voltage signal and the digital current signal, and display the digital voltage signal, the digital current signal and the signal frequency and voltage amplitude set by the keyboard module in real time, current amplitude.

Preferably, the optocoupler isolation module is used for isolating the sinusoidal pulse modulation signal through the optocoupler to obtain the isolated sinusoidal pulse modulation signal, and isolating the pulse signal through the optocoupler to obtain the isolated pulse signal.

Preferably, the voltage transformer module is used for converting strong AC voltage signals into voltage acquisition signals; the current transformer module is used for converting strong alternating current current signals into current acquisition signals; the voltage signal preprocessing module is used for The acquisition signal is filtered and preprocessed to obtain an analog voltage signal; the current signal preprocessing module is used to filter and preprocess the current acquisition signal to obtain an analog current signal; the AD sampling module is used to convert the analog voltage signal into a digital voltage signal, and convert the analog voltage signal into a digital voltage signal. The current signal is converted into a digital current signal, and the digital voltage signal and the digital current signal are transmitted to the control module; the keyboard module is used to set the signal frequency, voltage amplitude, and current amplitude to meet the different power supply requirements of the load, and is a matrix keyboard; the control module is used to generate sinusoidal pulse modulation signal and pulse signal according to digital voltage signal and digital current signal, and display digital voltage signal, digital current signal and the signal frequency, voltage amplitude, current set by the keyboard module in real time Amplitude; the optocoupler isolation module is used to isolate the sinusoidal pulse modulation signal through the optocoupler to obtain the isolated sinusoidal pulse modulation signal, and isolate the pulse signal through the optocoupler to obtain the isolated pulse signal; the full-bridge drive module The sinusoidal pulse modulation signal generated by the inverter generates a drive signal; the full-bridge inverter module inverts the DC signal into an AC signal according to the drive signal; the first LC filter module is used to filter the AC signal and output the filtered sinusoidal AC signal; The transformer isolation module is used for rectifying the sinusoidal AC signal after filtering to obtain an isolated sinusoidal AC signal through AC step-down and AC boosting; the full-bridge rectification module is used for rectifying the isolated sinusoidal AC signal to obtain a rectified DC signal; The second LC filter module is used for filtering the rectified DC signal and outputting the filtered DC signal; the boost boosting module boosts the voltage of the filtered DC signal according to the isolated pulse signal, and feeds back the DC signal after the voltage boost to the full-bridge inverter module to achieve energy return.

The effect of the utility model is that stable sinusoidal alternating current can be output, energy feedback is realized, the system is stable and the precision is high.

Description of drawings

Fig. 1: is the structural sketch of the utility model;

Fig. 2 is the circuit diagram of the full-bridge inverter module of the present invention;

Fig. 3: It is the circuit diagram of the full-bridge drive module of the utility model

Fig. 4: is the first LC filter module circuit diagram of the utility model;

Fig. 5: It is a schematic diagram of the transformer isolation module structure of the utility model;

Fig. 6 is the circuit diagram of the full-bridge rectifier module of the present invention;

Fig. 7: is the second LC filter module circuit diagram of the utility model;

FIG. 8 is a circuit diagram of a Boost boosting module of the present invention;

Fig. 9: It is the schematic diagram of the control module structure of the utility model

Figure 10: is a schematic diagram of the keyboard module structure of the present invention

Fig. 11: is the voltage transformer module circuit diagram of the utility model;

Fig. 12: It is the circuit diagram of the voltage signal preprocessing module of the utility model

Fig. 13: It is the circuit diagram of the current transformer module of the present utility model;

Figure 14: is the circuit diagram of the current signal preprocessing module of the present invention

Fig. 15: is the AD sampling module circuit diagram of the utility model;

FIG. 16 is a circuit diagram of an optocoupler isolation module of the present invention.

Detailed ways

In order to facilitate those skilled in the art to understand and implement the present utility model, the present utility model will be described in further detail below with reference to the accompanying drawings and embodiments. to limit the present invention.

Referring to FIG. 1, the technical solution adopted in the embodiment of the present invention is: an energy feedback device in a load test of a converter, comprising: a full-bridge inverter module 1, a full-bridge drive module 2, and a first LC filter module 3. Transformer isolation module 4, full bridge rectifier module 5, second LC filter module 6, Boost boost module 7, control module 8, keyboard module 9, voltage transformer module 10, voltage signal preprocessing module 11, current transformer module 12, current signal preprocessing module 13, AD sampling module 14, optocoupler isolation module 15;

The full-bridge inverter module 1, the first LC filter module 3, the transformer isolation module 4, the full-bridge rectifier module 5, the second LC filter module 6, and the boost booster module 7; the full-bridge inverter module 1 and the The boost module 7 is connected by wires; the full-bridge inverter module 1 is connected with the full-bridge drive module 2 by wires; the full-bridge drive module 2 is connected with the optocoupler isolation module 15; the The boost boosting module 7 is connected with the optocoupler isolation module 15; the first LC filter module 3 is respectively connected with the voltage transformer module 10 and the current transformer module 12 through wires in sequence; the voltage signal preprocessing The module 11 is connected with the voltage transformer module 10; the current signal preprocessing module 13 is connected with the current transformer module 12; the AD sampling module 14 is respectively connected with the voltage signal preprocessing module 11, the current signal The preprocessing module 13 is connected in sequence through wires; the control module 8 is respectively connected with the AD sampling module 14 , the optocoupler isolation module 15 and the keyboard module 9 in sequence through wires.

The full-bridge inverter module, the full-bridge drive module and the first LC filter module complete the DC-AC conversion function; the full-bridge rectifier module, the second LC filter module and the Boost boost module jointly complete the AC-DC conversion function, the conversion output is fed back to the front end of the full-bridge inverter module to achieve energy feedback.

The full-bridge inverter module inverts the DC signal into an AC signal according to the driving signal, and is composed of four low-power-consumption switch tubes CSD19536 and peripheral circuits.

The full-bridge driving module generates a driving signal according to the isolated sinusoidal pulse modulation signal, and is composed of two half-bridge driving chips UCC27211 and peripheral circuits.

The first LC filter module is used for filtering the AC signal and outputting the filtered sinusoidal AC signal.

The transformer isolation module is used to obtain the isolated sinusoidal AC signal from the filtered sinusoidal AC signal through AC step-down and AC boost, and is composed of a 220V/48V step-down transformer and a 48V/220V step-up transformer. The step-up transformer is used for AC step-down, and the 48V/220V step-up transformer is used for AC step-up.

The full-bridge rectifier module is used to rectify the isolated sinusoidal AC signal to obtain a rectified DC signal, and is composed of four diodes MBR10100CT.

The second LC filter module is used for filtering the rectified DC signal and outputting the filtered DC signal.

The boost boosting module boosts the voltage of the filtered DC signal according to the isolated pulse signal, and feeds back the DC signal after the voltage boost to the full-bridge inverter module to achieve energy return. The drive chip UCC27211, inductor, freewheeling Diode, switch tube CSD19536, filter capacitor.

The voltage transformer module is used to convert the AC strong voltage signal into a voltage acquisition signal, and is selected as a voltage transformer TV1013-1H.

The current transformer module is used to convert the AC strong current signal into the current acquisition signal, and is selected as a current transformer TA1015-2.

The voltage signal preprocessing module is used to filter and preprocess the voltage acquisition signal to obtain an analog voltage signal, and the model is an operational amplifier OPA2227.

The current signal preprocessing module is used to filter and preprocess the current acquisition signal to obtain an analog current signal, and the model is an operational amplifier OPA2227.

The AD sampling module is used to convert analog voltage signals into digital voltage signals, convert analog current signals into digital current signals, and transmit digital voltage signals and digital current signals to the control module, including analog-to-digital converter TLC3578, voltage Reference chip REF5040 and linear regulator LM1117.

The keyboard module is used to set the signal frequency, voltage amplitude, and current amplitude to meet different power supply requirements of loads, and is a matrix keyboard.

The control module is used to generate sinusoidal pulse modulation signals and pulse signals according to the digital voltage signal and the digital current signal, and display the digital voltage signal, the digital current signal and the signal frequency, voltage amplitude, and current amplitude set by the keyboard module in real time. , the selection is the control center F6638&FPGA with integrated LCD liquid crystal display.

The optocoupler isolation module is used for isolating the sinusoidal pulse modulation signal through the optocoupler to obtain the isolated sinusoidal pulse modulation signal, and isolating the pulse signal through the optocoupler to obtain the isolated pulse signal, and the optocoupler isolator ISO7240C is selected.

The full-bridge inverter module 1, the full-bridge drive module 2 and the first LC filter module 3 complete the DC-AC conversion function; the full-bridge rectifier module 5, the second LC filter module 6 and the boost booster module 7 jointly complete the AC-DC conversion Function, the conversion output is fed back to the front end of the full-bridge inverter module 1 to realize energy feedback; the other modules are used as peripheral parts.

Below in conjunction with Fig. 1 to Fig. 16, the specific embodiment of the present utility model is introduced as follows:

The voltage transformer module 10 is used for converting the AC strong voltage signal into a voltage acquisition signal; the current transformer module 12 is used for converting the AC strong current signal into a current acquisition signal; the voltage signal preprocessing module 11 is used for voltage The acquisition signal is filtered and preprocessed to obtain an analog voltage signal; the current signal preprocessing module 13 is used to filter and preprocess the current acquisition signal to obtain an analog current signal; the AD sampling module 14 is used to convert the analog voltage signal into a digital voltage signal, The analog current signal is converted into a digital current signal, and the digital voltage signal and the digital current signal are transmitted to the control module 8; the keyboard module 9 is used to set the signal frequency, voltage amplitude, and current amplitude to meet the power supply of different loads Demand is a matrix keyboard; the control module 8 is used to generate a sinusoidal pulse modulation signal and a pulse signal according to the digital voltage signal and the digital current signal, and display the digital voltage signal, the digital current signal and the signal frequency set by the keyboard module 9 in real time and voltage amplitude and current amplitude; the optocoupler isolation module 15 is used to isolate the sinusoidal pulse modulation signal through the optocoupler to obtain the isolated sinusoidal pulse modulation signal, and isolate the pulse signal through the optocoupler to obtain the isolated pulse signal; the The full-bridge drive module 2 generates a drive signal according to the isolated sinusoidal pulse modulation signal; the full-bridge inverter module 1 inverts the DC signal into an AC signal according to the drive signal; the first LC filter module 3 is used for the AC signal Filter and output the sinusoidal AC signal after filtering; the transformer isolation module 4 is used to obtain the isolated sinusoidal AC signal through AC step-down and AC boost; the full-bridge rectifier module 5 is used to rectify the isolated sinusoidal AC signal to obtain The DC signal after rectification; the second LC filter module 6 is used for filtering the DC signal after rectification and outputting the DC signal after filtering; the boosting module 7 boosts the voltage of the DC signal after filtering according to the pulse signal after isolation, The DC signal after the voltage rise is fed back to the full-bridge inverter module 1 to realize energy return.

Referring to FIG. 2 , the full-bridge inverter module 1 of this embodiment includes low-power-consumption switch tubes CSD19536 01 , 02 , 03 , 04 and peripheral circuits. A leakage resistor is placed between the gate and source of the switch tubes 01, 02, 03, and 04 for protection. The four switching tubes form a full-bridge conversion circuit, which is alternately turned on according to the sinusoidal law. The output voltage of the full-bridge inverter module 1 is a bipolar SPWM wave with a sinusoidal pulse width, followed by an LC low-pass filter to filter out the carrier and harmonic frequency components of the SPWM wave to obtain a low-frequency sinusoidal alternating current.

Referring to FIG. 3 , the full-bridge driving module 2 of this embodiment is composed of half-bridge driving chips UCC27211 21 and 22 and peripheral circuits. The VDD terminals of the half-bridge driver chips 21 and 22 are connected to the 12V power supply, the VSS terminal is connected to the system ground, the HB terminal is connected to the HS terminal through a bootstrap capacitor, and is connected to the sources of the high-side switch tubes 01 and 03 respectively, LI The terminal and the HI terminal are respectively connected to the SPWM wave output ports with complementary phases in the control module 8, the HO terminal is respectively connected to the gates of the high-side switch tubes 01 and 03 through the driving resistor, and the LO terminal is respectively connected to the low-side switch tube 02 through the driving resistor. , the gate of 04 is connected. A switching diode is reversely connected between the driving end and the gates of the switching tubes 01 , 02 , 03 , and 04 for adjusting the turn-on and turn-off speed thereof. The drains of the high-side switch tubes 01 and 03 are directly connected to the input DC voltage regulator, and the sources of the low-side switch tubes 02 and 04 are connected to the system ground.

Please refer to FIG. 4 , the first LC filter module 3 is composed of an inductor 31 and a capacitor 32 . The two input terminals are respectively connected to the connection between the source of the switch tube 01 and the drain of 02 and the connection between the source of the switch tube 03 and the drain of 04 in the full-bridge inverter module 1, and the output terminal outputs a sinusoidal AC signal.

Referring to FIG. 5 , the transformer isolation module 4 of this embodiment is composed of transformers 41 and 42 . The transformer 41 is connected to the output end of the first LC filter module 3 and is a 220V/48V step-down transformer. Transformer 42 is a 48V/220V step-up transformer. The transformer isolation module 4 transmits the sinusoidal AC signal 1:1 to the subsequent stage.

Referring to FIG. 6 , the full-bridge rectifier module 5 of this embodiment is composed of diodes 51 , 52 , 53 , and 54 . This module is connected to the rear stage of the transformer isolation module 4 to rectify the sinusoidal AC signal.

Referring to FIG. 7 , the second LC filter module 6 in this embodiment includes an inductor 61 and a capacitor 62 . This module is connected to the rear end of the full-bridge rectifier module 5 to reduce the pulsation coefficient of the rectified output voltage, thereby outputting an ideal DC signal.

Referring to FIG. 8 , the boost boosting module 7 of this embodiment includes an inductor 71 , a freewheeling diode 72 , a switch tube CSD19536 73 , a filter capacitor 74 and a driver chip UCC27211 75 . After the inductor 71 is connected to the second LC filter module 6, the diode 72 is connected in series in the circuit, and the switch tube 73 and the capacitor 74 are connected in parallel in the circuit. The HI end of the driver chip UCC27211 75 is connected to the PWM wave output port in the control module 8 , and the HO end is connected to the gate of the switch tube 73 through a drive resistor. After boosting, the output voltage is controlled above the input voltage of the full-bridge inverter module 1, which can realize energy return.

Referring to FIG. 9 , the control module 8 of this embodiment includes a control center F6638&FPGA 81 and an LCD liquid crystal display screen 82 . The control center 81 integrates the microcontroller MSP430F6638 and FPGA, so that they can jointly process signals and improve system performance; The software part controls the generation of two complementary SPWM waves and one PWM wave in the FPGA. The SPWM wave controls the full-bridge inverter module 1 to generate a sinusoidal AC signal, and the generated PWM wave controls the output voltage of the Boost boost module 7; Read the sampled voltage, current value and keyboard setting value in real time, and control the LCD display; further process the sampled signal in MSP430F6638, use the PID algorithm to stabilize the sinusoidal AC output after DC-AC conversion at 25V and control the DC after Boost boost. The output voltage is higher than the input voltage of the full-bridge inverter module 1 .

Referring to FIG. 10 , the keyboard module 9 of this embodiment includes a matrix keyboard. The matrix keyboard is connected to the 8 IO ports with interrupt function of F6638&FPGA81, and the key value is obtained by the line scan method and sent to the control center 81 for further processing.

Referring to FIG. 11 , the voltage transformer module 10 of this embodiment includes a voltage transformer TV1013-1H 81 . This module is connected to the rear stage of the first LC filter module 3 , and converts the voltage signal output by the DC-AC conversion into a weak voltage signal that can be sampled by the AD chip 1401 .

Referring to FIG. 12 , the voltage signal preprocessing module 11 of this embodiment includes operational amplifiers OPA22271101 and 1102 and peripheral circuits. This module is connected to the rear stage of the voltage transformer module 10, and performs filtering and preprocessing on the weak voltage signal.

Referring to FIG. 13 , the current transformer module 12 of this embodiment includes a current transformer TA1015-2 1201 . This module is connected to the rear stage of the first LC filter module 3 , and converts the current signal output by the DC-AC conversion into a weak voltage signal that can be sampled by the AD chip 1401 .

Referring to FIG. 14 , the current signal preprocessing module 13 of this embodiment includes operational amplifiers OPA2227 1301 and 1302 and peripheral circuits. This module is connected to the rear stage of the voltage transformer module 12, and performs filtering and preprocessing on the weak voltage signal.

Referring to FIG. 15 , the AD sampling module 14 of this embodiment includes an AD chip TLC3578 1401 , a voltage reference chip REF5040 1402 and a linear voltage regulator LM1117 1403 . The SCLK, SDI, SDO and CS terminals of the AD chip 1401 are respectively connected to any IO port of F6638 & FPGA 81 , the REFP terminal is connected to the output terminal of the reference chip 1402 , and the DVDD terminal is connected to the output terminal of the voltage regulator 1403 . The VIN terminals of the reference chip 1402 and the voltage regulator 1403 are both connected to +5V.

Referring to FIG. 16 , the optocoupler isolation module 15 of this embodiment is composed of an optocoupler isolator ISO7240C 1501 and a peripheral circuit. The optocoupler isolation module 15 is used to protect the FPGA, and is connected to its SPWM wave and PWM wave output ports. The isolated output is then sent to the full-bridge inverter module 1 and the boost booster module 7 respectively.

Although this manual uses a lot of full-bridge inverter module, full-bridge drive module, first LC filter module, transformer isolation module, full-bridge rectifier module, second LC filter module, boost boost module, control module, keyboard module , voltage transformer module, voltage signal preprocessing module, current transformer module, current signal preprocessing module, AD sampling module, optocoupler isolation module and other terms, but does not exclude the possibility of using other terms. These terms are only used to describe the essence of the present invention more conveniently, and it is contrary to the spirit of the present invention to interpret them as any kind of additional limitations.

It should be understood that the above description of the preferred embodiments is relatively detailed, and therefore should not be considered as a limitation on the protection scope of the present invention. Under the inspiration of the present invention, those of ordinary skill in the art can In the case of the scope of protection of the claims of the utility model, substitutions or deformations can also be made, which all fall within the scope of protection of the present utility model, and the scope of the claimed protection of the present utility model shall be subject to the appended claims.

Claims (8)

1. an energy feedback device in a converter load test, characterized in that it comprises: a full-bridge inverter module, a full-bridge drive module, the first LC filter module, a transformer isolation module, a full-bridge rectifier module, the second LC Filtering module, Boost boosting module, control module, keyboard module, voltage transformer module, voltage signal preprocessing module, current transformer module, current signal preprocessing module, AD sampling module, optocoupler isolation module; The full-bridge inverter module, the first LC filter module, the transformer isolation module, the full-bridge rectifier module, the second LC filter module, and the Boost boosting module are sequentially connected in series through wires; the full-bridge inverter module and the The boost boosting module is connected by wires; the full-bridge inverter module is connected with the full-bridge drive module by wires; the full-bridge drive module is connected with the optocoupler isolation module; the boost booster module is connected with the optocoupler The isolation module is connected; the first LC filter module is respectively connected with the voltage transformer module and the current transformer module through wires in sequence; the voltage signal preprocessing module is connected with the voltage transformer module; the current signal The preprocessing module is connected with the current transformer module; the AD sampling module is respectively connected with the voltage signal preprocessing module and the current signal preprocessing module through wires in sequence; the control module is respectively connected with the AD sampling module , the optocoupler isolation module and the keyboard module are connected in turn by wires. 2 . The energy feedback device in the load test of the converter according to claim 1 , wherein the full-bridge inverter module inverts the DC signal into an AC signal according to the driving signal; the full-bridge driving module according to the The isolated sinusoidal pulse modulation signal generates a drive signal; the first LC filter module is used for filtering the AC signal and outputting the filtered sinusoidal AC signal. 3. The energy feedback device in the converter load test according to claim 1, wherein the transformer isolation module is used to obtain the isolated sinusoidal AC signal from the filtered sinusoidal AC signal through AC step-down and AC boost The signal is composed of a 220V/48V step-down transformer and a 48V/220V step-up transformer. The 220V/48V step-down transformer is used for AC step-down, and the 48V/220V step-up transformer is used for AC step-up; the full bridge The rectifier module is used to rectify the isolated sinusoidal AC signal to obtain a rectified DC signal; the second LC filter module is used to filter the rectified DC signal and output the filtered DC signal; The signal boosts the voltage of the filtered DC signal, and the DC signal after the voltage boost is fed back to the full-bridge inverter module to achieve energy return. 4 . The energy feedback device in the load test of the converter according to claim 1 , wherein the voltage transformer module is used for converting the AC strong voltage signal into a voltage acquisition signal; the current transformer module is used for Converting a strong AC current signal into a current acquisition signal; the voltage signal preprocessing module is used for filtering and preprocessing the voltage acquisition signal to obtain an analog voltage signal; the current signal preprocessing module is used for filtering and preprocessing the current acquisition signal to obtain an analog current Signal. 5 . The energy feedback device in a load test of a converter according to claim 1 , wherein the AD sampling module is used to convert an analog voltage signal into a digital voltage signal, and convert an analog current signal into a digital current. 6 . The digital voltage signal and the digital current signal are transmitted to the control module. 6. The energy feedback device in the converter load test according to claim 1, wherein the keyboard module is used to set the signal frequency, voltage amplitude, and current amplitude to meet the different power supply requirements of the load, for Matrix keyboard. 7 . The energy feedback device in the load test of the converter according to claim 1 , wherein the control module is used to generate sinusoidal pulse modulation signals and pulse signals according to digital voltage signals and digital current signals, and display them in real time. 8 . The digital voltage signal, the digital current signal, and the signal frequency, voltage amplitude, and current amplitude set by the keyboard module. 8. The energy feedback device in the converter load test according to claim 1, wherein the optocoupler isolation module is used to isolate the sinusoidal pulse modulation signal through the optocoupler to obtain the isolated sinusoidal pulse modulation signal, and the The pulse signal is isolated by the optocoupler to obtain the isolated pulse signal.