Pulse current output system and method based on Buck circuit

Abstract

The invention relates to a pulse current output system and method based on a Buck circuit. The pulse current output system comprises a remote monitoring platform, a high-voltage power supply device, a master converter device, a slave converter device and a plurality of energy storage capacitor devices, aC positive and negative output ends of the high-voltage power supply device are correspondingly and electrically connected with zero line ends and live line ends of the master and slave converter devices respectively, and DC positive and negative output ends of the high-voltage power supply device are correspondingly and electrically connected with DC positive and negative input ends of the master and slave converter devices and each energy storage capacitor device respectively; the positive output end and the signal receiving and transmitting end of the main converter device are electrically connected with the positive output end and the signal receiving and transmitting end of the slave converter device, and the data end of the remote monitoring platform is electrically connected with the data end of the high-voltage power supply device and the data end of the main converter device. According to the invention, short-time pulse current can be conveniently output so as to simulate or test large-current experiment working conditions or instantaneous impact current, the pulse current can be adjusted, the duration can be adjusted, remote control can be realized, the cost is low, the control effect is good, and the stability is high.

Description

Technical Field

[0001] The present invention relates to the technical field of pulse current, and in particular to a pulse current output system based on a Buck circuit. Background Art

[0002] Buck circuit is a DC-DC converter based on the principle of inductive energy storage, which involves the basic principles of electromagnetic induction and electric energy conversion in physics. In the Buck circuit, the DC voltage provided by the input power supply is converted into an adjustable low voltage output by controlling the on and off state of the switch tube by controlling the PWM wave with a variable duty cycle, thereby meeting the power supply requirements of different circuits.

[0003] Specifically, when the inductor in the Buck circuit is in the on state, it converts the current through the magnetic field of the inductor's center core into magnetic energy and stores the magnetic energy in the inductor. In the off state, due to the self-inductance of the inductor, the magnetic field will generate voltage, converting electromagnetic energy into electrical energy, and supplying power to the load through the output end. Therefore, by controlling the on and off states of the switch tube, the periodic conversion and regulation of electrical energy between the capacitor and the inductor is achieved, and a stable DC voltage is finally output.

[0004] In addition, in order to ensure a stable output voltage, the Buck circuit usually adopts negative feedback control, which samples the output voltage and feeds it back to the controller. The controller then adjusts the duty cycle of the output PWM wave and controls the on-time and off-time of the switch tube to keep the output voltage within the predetermined range.

[0005] In practice, in order to simulate and test the experimental object, a large current experiment or a transient impulse current is usually required. The device for providing the test current in the prior art usually cannot be remotely controlled, has high cost, poor stability, and poor control effect. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a pulse current output system and method based on Buck circuit in view of the above-mentioned deficiencies in the prior art.

[0007] The technical solution of the present invention to solve the above technical problems is as follows: a pulse current output system based on Buck circuit, comprising a remote monitoring platform, a high voltage power supply device, a main current conversion device, a slave current conversion device and a plurality of energy storage capacitor devices;

[0008] The AC positive and negative output terminals of the high-voltage power supply device are electrically connected to the neutral terminal and the live terminal of the main converter device and the slave converter device respectively, the DC positive and negative output terminals of the high-voltage power supply device are electrically connected to the DC positive and negative input terminals of the main converter device, the slave converter device and each of the energy storage capacitor devices respectively, the positive output terminal of the main converter device is electrically connected to the positive output terminal of the slave converter device and serves as the output positive electrode of the pulse current, the negative output terminal of the high-voltage power supply device serves as the output negative electrode of the pulse current, the signal transceiver terminal of the main converter device is electrically connected to the signal transceiver terminal of the slave converter device respectively, and the data terminal of the remote monitoring platform is electrically connected to the data terminal of the high-voltage power supply device and the data terminal of the main converter device respectively;

[0009] The remote monitoring platform is used to set input and output electrical parameters, and control the high-voltage power supply device to start or stop boosting the main converter device, the slave converter device and the energy storage capacitors in the multiple energy storage capacitor devices;

[0010] The high-voltage power supply device is used to provide AC power to the main converter device, the slave converter device and the multiple energy storage capacitor devices respectively; and is also used to boost the voltage of the main converter device, the slave converter device and the energy storage capacitors in the multiple energy storage capacitor devices according to the control instructions of the remote monitoring platform;

[0011] The remote monitoring platform is also used to send control instructions to the main converter device;

[0012] The main inverter device is used to start or stop controlling the main inverter device, the slave inverter device and the energy storage capacitor in the energy storage capacitor device to release electric energy according to the control instructions of the remote monitoring platform, and is also used to control it to output pulse current synchronously with the slave inverter device, and is also used to communicate with the remote monitoring platform.

[0013] The beneficial effects of the present invention are as follows: the pulse current output system based on the Buck circuit of the present invention controls the high-voltage power supply device to boost the voltage of the main converter, the slave converter and the energy storage capacitors in the multiple energy storage capacitor devices through a remote monitoring platform, and then the remote monitoring platform controls the main converter to start controlling the main converter, the slave converter and the energy storage capacitors in the energy storage capacitor devices to release electric energy, and outputs the pulse current through the positive and negative poles of the pulse current output, and at the same time, the remote monitoring platform monitors the voltage waveform and current waveform of the pulse current in real time, and can conveniently and quickly output short-time pulse current to simulate or test the large current experimental conditions or instantaneous impact current required by the experimental object under test, the pulse current size can be adjusted, the duration can be adjusted, and it needs to have local control and remote control functions, and its cost is low, the control effect is good, and the stability is high.

[0014] On the basis of the above technical solution, the present invention can also be improved as follows:

[0015] Further: the main converter device includes a plurality of Buck modules CNVTM1-CNTVMn, parallel inductors LM1-LM 2n , voltage sensor V2, main current sensor, switch K2 and discharge resistor R, the DC positive and negative output terminals J2-1 and J2-2 of the high-voltage power supply device are respectively electrically connected to the DC positive and negative input terminals VI N+ and VI N- of the Buck modules CNVTM1-CNTVMn, and boost the energy storage capacitor in the Buck modules CNVTM1-CNTVMn, the neutral line terminal and the live line terminal of the high-voltage power supply device are respectively electrically connected to the neutral line terminal and the live line terminal of each Buck module CNVTM1-CNTVMn, and power the Buck modules CNVTM1-CNTVMn, the signal output terminals VOUT1 and VOUT2 of the Buck modules CNVTM1-CNTVMn are respectively electrically connected to the parallel inductors LM1 and LM2, the parallel inductors LM3 and LM4...parallel inductors LM 2n-1 and LM 2n The parallel inductors LM1 and LM2, the parallel inductors LM3 and LM4, and the parallel inductors LM 2n-1 and LM 2n The other end is respectively electrically connected to the pulse current output positive terminal J3-1, a switch K2 and a discharge resistor R are connected in series between the DC negative output end of the high-voltage power supply device and the pulse current output positive terminal J3-1, the voltage sensor V2 is electrically connected between the DC negative output end of the high-voltage power supply device and the pulse current output positive terminal J3-1, the pulse current output positive terminal J3-1 is electrically connected to the main current sensor, the data end LAN of the Buck module CNVTM1 is electrically connected to the data end of the remote monitoring platform, and the transceiver signal ends CAN-H and CAN-L of the Buck main modules CNVTM1-CNTVMn are electrically connected to the CAN bus terminals J4-1 and J4-2 respectively.

[0016] The beneficial effect of the above further scheme is: power is supplied to each Buck module in the main converter by the high-voltage power supply device, and at the same time, the energy storage capacitor in the Buck module CNVTM1-CNTVMn is boosted to ensure that the energy storage capacitor can release enough energy during operation to achieve the effect of pulse current output. At the same time, the voltage at the pulse current output end is detected in real time by the voltage sensor V2, and the transceiver signal terminals CAN-H and CAN-L of the Buck module CNVTM1-CNTVMn are electrically connected to the CAN bus terminals J4-1 and J4-2 respectively, so that the Buck module in the main converter and the Buck module in the slave converter can be easily output synchronously.

[0017] Further: the slave converter includes a plurality of Buck modules CNVTS1-CNTVSm and parallel inductors LS1-LS 2m The DC positive and negative output terminals J2-1 and J2-2 of the high-voltage power supply device are respectively electrically connected to the DC positive and negative input terminals VI N+ and VI N- of each of the Buck modules CNVTS1-CNTVSm, and boost the energy storage capacitor in the Buck modules CNVTS1-CNTVSm. The neutral line terminal and the live line terminal of the high-voltage power supply device are respectively electrically connected to the neutral line terminal and the live line terminal of each of the Buck modules CNVTS1-CNTVSm, and supply power to the Buck modules CNVTS1-CNTVSm. The signal output terminals VOUT1 and VOUT2 of the Buck modules CNVTS1-CNTVSm are respectively electrically connected to the parallel inductors LS1 and LS2, the parallel inductors LS3 and LS4...the parallel inductors LS 2m-1 and LS 2m The parallel inductors LS1 and LS2, the parallel inductors LS3 and LS4, and the parallel inductors LS 2m-1 and LS 2m The other end is electrically connected to the pulse current output positive terminal J3-1 respectively, and the receiving and transmitting signal ends CAN-H and CAN-L of all the Buck modules CNVTS1-CNTVSm are electrically connected to the CAN bus terminals J4-1 and J4-2 respectively.

[0018] The beneficial effect of the above further scheme is: the high-voltage power supply device is used to power each Buck module in the slave converter, and at the same time, the energy storage capacitor in the Buck module is boosted to ensure that the energy storage capacitor can release enough energy during operation to achieve the effect of pulse current output. At the same time, the transceiver signal terminals CAN-H and CAN-L of the Buck modules CNVTS1-CNTVSm are electrically connected to the CAN bus terminals J4-1 and J4-2 respectively, so that the Buck module in the main converter and the Buck module in the slave converter can be easily synchronized. Output.

[0019] Further: the Buck modules in the master converter and the slave converter each include a plurality of parallel Buck branches, a tank circuit C1 and a voltage sensor V1, and each of the Buck branches includes an IGBT module, each of the IGBT modules includes an upper bridge arm IGBT tube, a lower bridge arm IGBT tube, a branch current sensor, an absorption capacitor and a filter inductor, the collector of the upper bridge arm IGBT tube is electrically connected to the DC positive output terminal J2-1 of the high-voltage power supply device as the positive input terminal VI N+, the emitter of the upper bridge arm IGBT tube and the collector of the lower bridge arm IGBT tube are respectively electrically connected to one end of the corresponding filter inductor with the corresponding branch current sensor, the other end of the filter inductor is electrically connected to one end of the corresponding parallel inductor as the signal output terminal VOUT1 or VOUT2, the emitter of the lower bridge arm IGBT tube is electrically connected to the DC negative output terminal J2-2 of the high-voltage power supply device as the negative input terminal VI N-, the collector of the upper bridge arm IGBT tube is electrically connected to the lower bridge arm I The corresponding absorption capacitor is electrically connected between the emitters of the GBT tubes, and the voltage sensor V1 and the energy storage capacitor C1 are connected in parallel between the positive input terminal VI N+ and the negative input terminal VI N- of each Buck branch.

[0020] The beneficial effect of the above further scheme is: the PWM signal for output current control is received by the upper bridge arm IGBT tube, and the gate signal of the lower bridge arm IGBT tube is always at a low level, and only the anti-parallel diode is used to continue the inductor current, and the high-frequency circulating current between the branches can be reduced by connecting multiple Buck branches in parallel and cooperating with the filter inductor. The energy storage circuit can be used to boost energy storage to ensure that the energy storage capacitor can release enough energy during operation to achieve the effect of pulse current output. The voltage sensor V1 is used to detect the real-time voltage across the energy storage capacitor and feed it back to the MCU microprocessor in the corresponding Buck module. After the MCU microprocessor calculates the output current collected on each Buck branch, the MCU microprocessor outputs the corresponding PWM signal. The function of the absorption capacitor is to absorb the peak voltage and peak current in the DC input signal to make the output result on each Buck branch smoother.

[0021] Further: the energy storage capacitor device includes a plurality of CAP modules and fuses having the same number and corresponding one to one with the CAP modules, the positive electrode of the CAP module is electrically connected to the DC positive output terminal J1-1 of the high-voltage power supply device through the corresponding fuse, and the negative electrode of the CAP module is electrically connected to the DC negative output terminal J1-2 of the high-voltage power supply device.

[0022] The beneficial effect of the above further solution is that the capacitors in the CAP module are connected by laminated busbars, and the positive electrode of each energy storage capacitor module is designed with a fuse to ensure the safe use of each module.

[0023] The present invention also provides a pulse current output method based on a Buck circuit, which adopts the pulse current output system based on a Buck circuit, and is characterized in that it includes the following steps:

[0024] Set the preset ranges of input voltage, input current, output voltage and output current, and pulse current output time on the remote monitoring platform;

[0025] The remote monitoring platform sends a control instruction to the high-voltage power supply device, controls the high-voltage power supply device to start providing AC power to the main converter device, the slave converter device and the multiple energy storage capacitor devices, and controls the high-voltage power supply device to start boosting the energy storage capacitors in the main converter device, the slave converter device and the multiple energy storage capacitor devices until the boosting of the energy storage capacitors is completed;

[0026] The remote monitoring platform controls the high-voltage power supply device to stop providing AC power to the main converter device, the slave converter device and the plurality of energy storage capacitor devices respectively;

[0027] The remote monitoring platform controls the main converter device to start controlling the main converter device, the slave converter device and the energy storage capacitor in the energy storage capacitor device to release electric energy, and at the same time, the remote monitoring platform displays the voltage waveform and current waveform at the output end of the main converter device and the slave converter device;

[0028] After use, the control switch K2 is disconnected, and the remaining unconsumed electric energy in the energy storage capacitor device is released through the discharge resistor R.

[0029] On the basis of the above technical solution, the present invention can also be improved as follows:

[0030] Further: the remote monitoring platform controls the main converter device to start controlling the main converter device, and the converter device and the energy storage capacitor in the energy storage capacitor device release electric energy, specifically including the following steps:

[0031] The first Buck module CNVTM1 in the main converter device sends a control signal from the remote monitoring platform to the remaining Buck modules CNVTM2-CNVTMn in the main converter device and the Buck modules CNVTS1-CNVTSm in the slave converter device via the CAN bus, so that all Buck modules output synchronously;

[0032] Each Buck branch generates a PWM wave signal according to the current signal and voltage signal collected by the corresponding branch current sensor and voltage sensor V1 respectively;

[0033] The PWM wave signal drives the corresponding IGBT tube in the Buck branch to turn on and off, so as to perform closed-loop control of the pulse current.

[0034] The beneficial effect of the above further scheme is: by controlling the remaining Buck modules CNVTM2-CNVTMn in the main converter and the Buck modules CNVTS1-CNVTSm in the slave converter through the first Buck module CNVTM1 in the main converter, it is possible to ensure the synchronous output of all Buck modules, and by generating a PWM wave signal based on the current signal and voltage signal collected by the branch current sensor and the voltage sensor V1, a closed-loop control of the pulse current is formed to ensure the stability of the pulse current. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a schematic diagram of the structure of a pulse current output system based on a Buck circuit according to an embodiment of the present invention;

[0036] Figure 2 A main circuit schematic diagram of a main converter device according to an embodiment of the present invention;

[0037] Figure 3A schematic diagram of a main circuit of a slave current converter according to an embodiment of the present invention;

[0038] Figure 4 A circuit schematic diagram of an IGBT module according to an embodiment of the present invention;

[0039] Figure 5 This is a main circuit diagram of a Buck module according to an embodiment of the present invention;

[0040] Figure 6 This is a main circuit schematic diagram of an energy storage capacitor device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0041] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0042] like Figure 1 As shown, a pulse current output system based on Buck circuit includes a remote monitoring platform, a high voltage power supply device, a main current conversion device, a slave current conversion device and a plurality of energy storage capacitor devices;

[0043] The AC (220V) positive and negative output terminals L and N of the high-voltage power supply device are respectively electrically connected to the neutral terminal N and the live terminal L of the main converter device and the slave converter device, the DC (700V) positive and negative output terminals DC+ and DC- of the high-voltage power supply device are respectively electrically connected to the DC positive and negative input terminals VI N+ and VI N- corresponding to the main converter device, the slave converter device and each of the energy storage capacitor devices, the positive output terminal VOUT+ of the main converter device is electrically connected to the positive output terminal VOUT+ of the slave converter device and serves as the output positive electrode of the pulse current, the negative output terminal DC- of the high-voltage power supply device serves as the output negative electrode of the pulse current, the signal transceiver terminals CAN-H and CAN-L of the main converter device are respectively electrically connected to the signal transceiver terminals CAN-H and CAN-L of the slave converter device, and the data terminals LAN-1 and LAN-2 of the remote monitoring platform are respectively electrically connected to the data terminal of the high-voltage power supply device LAN and the data terminal LAN of the main converter device;

[0044] The remote monitoring platform is used to set input and output electrical parameters, receive control instructions from the operation screen, and control the high-voltage power supply device to start or stop boosting the main converter device, the slave converter device, and the energy storage capacitors in the multiple energy storage capacitor devices;

[0045] In the embodiment of the present invention, the remote monitoring platform communicates with the local operation screen through the network port and receives the instructions of the remote monitoring station.

[0046] The high-voltage power supply device is used to provide AC power to the main converter device, the slave converter device and the multiple energy storage capacitor devices respectively; and is also used to boost the voltage of the main converter device, the slave converter device and the energy storage capacitors in the multiple energy storage capacitor devices according to the control instructions of the remote monitoring platform;

[0047] Here, the high-voltage power supply device supplies power to the MCU microprocessor and drive circuit in the main converter and slave converter, and also supplies power to the main converter, slave converter, and cooling fan in the capacitor device to ensure that each module can realize various functions under normal conditions.

[0048] Specifically, the positive pole DC+ and the negative pole DC- of the DC700V output port of the high-voltage power supply device are respectively connected to the positive input port and the negative input port of each energy storage capacitor device, and the positive pole DC+ and the negative pole DC- of the DC700V output port are respectively electrically connected to the port VI N+ and the port VI N- of the main converter device and the slave converter device. The main function of DC700V is to boost the voltage of the energy storage capacitor in the main converter device, the slave converter device and the capacitor device to ensure that the energy storage capacitor can release enough energy during operation to achieve the effect of pulse current output.

[0049] The remote monitoring platform is also used to send control instructions to the main converter device;

[0050] The main inverter device is used to start or stop controlling the main inverter device, the slave inverter device and the energy storage capacitor in the energy storage capacitor device to release electric energy according to the control instructions of the remote monitoring platform, and is also used to control it to output pulse current synchronously with the slave inverter device, and is also used to communicate with the remote monitoring platform.

[0051] Here, the main converter also needs to communicate with the local operation panel through the network port, receive control instructions from the operation panel, and display the corresponding voltage and current on the operation panel.

[0052] The Buck circuit-based pulse current output system of the present invention controls the high-voltage power supply device to boost the voltage of the main converter, the slave converter and the energy storage capacitors in the multiple energy storage capacitor devices through a remote monitoring platform, and then controls the main converter to start and control the main converter, the slave converter and the energy storage capacitors in the energy storage capacitor devices to release electric energy, and outputs pulse current through the positive and negative electrodes of the pulse current output. At the same time, the remote monitoring platform monitors the voltage waveform and current waveform of the pulse current in real time, and can conveniently and quickly output short-time pulse current to simulate or test the large current experimental conditions or instantaneous impact current required by the experimental object under test. The pulse current size can be adjusted, the duration can be adjusted, and it needs to have local control and remote control functions, and has low cost, good control effect and high stability.

[0053] like Figure 2 As shown, in one or more embodiments of the present invention, the main converter includes a plurality of Buck modules CNVTM1-CNTVMn, parallel inductors LM1-LM 2n , voltage sensor V2, main current sensor, switch K2 and discharge resistor R, the DC positive and negative output terminals J2-1 and J2-2 of the high-voltage power supply device are respectively electrically connected to the DC positive and negative input terminals VI N+ and VI N- of the Buck modules CNVTM1-CNTVMn, and boost the energy storage capacitor in the Buck modules CNVTM1-CNTVMn, the neutral line terminal and the live line terminal of the high-voltage power supply device are respectively electrically connected to the neutral line terminal and the live line terminal of each Buck module CNVTM1-CNTVMn, and power the Buck modules CNVTM1-CNTVMn, the signal output terminals VOUT1 and VOUT2 of the Buck modules CNVTM1-CNTVMn are respectively electrically connected to the parallel inductors LM1 and LM2, the parallel inductors LM3 and LM4...parallel inductors LM 2n-1 and LM 2n The parallel inductors LM1 and LM2, the parallel inductors LM3 and LM4, and the parallel inductors LM 2n-1 and LM 2n The other end is respectively electrically connected to the pulse current output positive terminal J3-1, a switch K2 and a discharge resistor R are connected in series between the DC negative output end of the high-voltage power supply device and the pulse current output positive terminal J3-1, the voltage sensor V2 is electrically connected between the DC negative output end of the high-voltage power supply device and the pulse current output positive terminal J3-1, the pulse current output positive terminal J3-1 is electrically connected to the main current sensor, the data end LAN of the Buck module CNVTM1 is electrically connected to the data end of the remote monitoring platform, and the transceiver signal ends CAN-H and CAN-L of the Buck main modules CNVTM1-CNTVMn are electrically connected to the CAN bus terminals J4-1 and J4-2 respectively. The high-voltage power supply device is used to power each Buck module in the main converter, and at the same time, the energy storage capacitor in the Buck module CNVTM1-CNTVMn is boosted to ensure that the energy storage capacitor can release enough energy during operation to achieve the effect of pulse current output. At the same time, the voltage sensor V2 is used to detect the voltage at the pulse current output end in real time, and the transceiver signal terminals CAN-H and CAN-L of the Buck module CNVTM1-CNTVMn are electrically connected to the CAN bus terminals J4-1 and J4-2 respectively, so that the Buck module in the main converter and the Buck module in the slave converter can be easily output synchronously.

[0054] like Figure 3 As shown, in one or more embodiments of the present invention, the slave converter includes a plurality of Buck modules CNVTS1-CNTVSm and parallel inductors LS1-LS 2m The DC positive and negative output terminals J2-1 and J2-2 of the high-voltage power supply device are respectively electrically connected to the DC positive and negative input terminals VI N+ and VI N- of each of the Buck modules CNVTS1-CNTVSm, and boost the energy storage capacitor in the Buck modules CNVTS1-CNTVSm. The neutral line terminal and the live line terminal of the high-voltage power supply device are respectively electrically connected to the neutral line terminal and the live line terminal of each of the Buck modules CNVTS1-CNTVSm, and supply power to the Buck modules CNVTS1-CNTVSm. The signal output terminals VOUT1 and VOUT2 of the Buck modules CNVTS1-CNTVSm are respectively electrically connected to the parallel inductors LS1 and LS2, the parallel inductors LS3 and LS4...the parallel inductors LS 2m-1 and LS 2m The parallel inductors LS1 and LS2, the parallel inductors LS3 and LS4, and the parallel inductors LS 2m-1 and LS 2m The other end is electrically connected to the pulse current output positive terminal J3-1 respectively, and the transceiver signal terminals CAN-H and CAN-L of all the Buck modules CNVTS1-CNTVSm are electrically connected to the CAN bus terminals J4-1 and J4-2 respectively. The high-voltage power supply device is used to power each Buck module in the slave converter, and at the same time, the energy storage capacitor in the Buck module is boosted to ensure that the energy storage capacitor can release enough energy during operation to achieve the effect of pulse current output. At the same time, the transceiver signal terminals CAN-H and CAN-L of the Buck modules CNVTS1-CNTVSm are electrically connected to the CAN bus terminals J4-1 and J4-2 respectively, so that the Buck module in the master converter and the Buck module in the slave converter can be easily synchronized. Output.

[0055] It should be pointed out that in the present invention, the slave converter is not provided with a discharge circuit. After the test, the unconsumed electric energy on the energy storage capacitor in the slave converter will be consumed by the discharge circuit R in the master converter.

[0056] The VOUT+ of the main converter is connected to the VOUT+ of the slave converter as the positive electrode interface for pulse current output, and the negative electrode of the DC700V output port is used as the negative electrode interface for pulse current output. Finally, the ultra-large instantaneous current generated by the 12 Buck modules is output to the equivalent loop impedance through these two leads.

[0057] like Figure 4 and Figure 5 As shown, in one or more embodiments of the present invention, the Buck modules in the master converter and the slave converter each include six parallel Buck branches, a tank circuit C1 and a voltage sensor V1, and each of the Buck branches includes an IGBT module, each IGBT module includes an upper bridge arm IGBT tube, a lower bridge arm IGBT tube, a branch current sensor, an absorption capacitor (C2, C3, C4, C5, C6 or C7) and a filter inductor (L1, L2, L3, L4, L5 or L6), the collector of the upper bridge arm IGBT tube is electrically connected to the DC positive output terminal J2-1 of the high-voltage power supply device as the positive input terminal VI N+, and the emitter of the upper bridge arm IGBT tube is electrically connected to the lower bridge arm I The collector of the IGBT tube is respectively electrically connected to one end of the corresponding filter inductor (L1, L2, L3, L4, L5 or L6) with the corresponding branch current sensor, the other end of the filter inductor (L1, L2, L3, L4, L5 or L6) is electrically connected to one end of the corresponding parallel inductor as the signal output end VOUT1 or VOUT2, the emitter of the lower bridge arm IGBT tube is electrically connected to the DC negative output terminal J2-2 of the high-voltage power supply device as the negative input terminal VI N-, the collector of the upper bridge arm IGBT tube and the emitter of the lower bridge arm IGBT tube are electrically connected with the corresponding absorption capacitor (C2, C3, C4, C5, C6 or C7), and the voltage sensor V1 and the energy storage capacitor C1 are connected in parallel between the positive input terminal VIN+ and the negative input terminal VI N- of each Buck branch.

[0058] Specifically, the terminals 3 of IGBT1-IGBT3 are respectively connected to the filter inductors L1-L3, the filter inductors L1-L3 are connected to the output port VOUT1, the terminals 3 of IGBT4-IGBT6 are respectively connected to the filter inductors L4-L6, the filter inductors L4-L6 are connected to the output port VOUT2, and every three Buck branches in each Buck module are connected in parallel. After parallel connection, the three IGBT modules of the parallel branches are controlled by carrier synchronization to reduce the high-frequency circulating current between the parallel branches. Considering that the PWM pulse signal will have a certain synchronization error, the corresponding filter inductor must be used to reduce the high-frequency circulating current.

[0059] The PWM signal for output current control is received by the upper bridge arm IGBT tube, and the gate signal of the lower bridge arm IGBT tube is always at a low level. Only the anti-parallel diode is used to continue the inductor current. By connecting multiple Buck branches in parallel and cooperating with the filter inductor, the high-frequency circulating current between the branches can be reduced. The energy storage circuit can be used to boost energy storage to ensure that the energy storage capacitor can release enough energy during operation to achieve the effect of pulse current output. The voltage sensor V1 is used to detect the real-time voltage across the energy storage capacitor and feed it back to the MCU microprocessor in the corresponding Buck module. After the MCU microprocessor calculates the output current collected on each Buck branch, the MCU microprocessor outputs the corresponding PWM signal. The function of the absorption capacitor is to absorb the peak voltage and peak current in the DC input signal to make the output result on each Buck branch smoother.

[0060] like Figure 6 As shown, in one or more embodiments of the present invention, the energy storage capacitor device includes a plurality of CAP modules CAP1-CAPk and ten fuses F1-Fk, the positive pole of the CAP module CAP1-CAPk is electrically connected to the DC positive output terminal J1-1 of the high-voltage power supply device through the corresponding fuse F1-Fk, and the negative pole of the CAP module CAP1-CAPk is electrically connected to the DC negative output terminal J1-2 of the high-voltage power supply device. The capacitors in the CAP modules CAP1-CAPk are connected by laminated busbars, and the positive pole of each energy storage capacitor module is designed with a fuse to ensure the safe use of each module.

[0061] The present invention also provides a pulse current output method based on a Buck circuit, which adopts the pulse current output system based on a Buck circuit, and is characterized in that it includes the following steps:

[0062] S1: Set the preset ranges of input voltage, input current, output voltage and output current and pulse current output time on the remote monitoring platform;

[0063] S2: The remote monitoring platform sends a control instruction to the high-voltage power supply device, controls the high-voltage power supply device to start providing AC power to the main converter device, the slave converter device and the multiple energy storage capacitor devices, and controls the high-voltage power supply device to start boosting the energy storage capacitors in the main converter device, the slave converter device and the multiple energy storage capacitor devices until the boosting of the energy storage capacitors is completed;

[0064] S3: The remote monitoring platform controls the high-voltage power supply device to stop providing AC power to the main converter device, the slave converter device and the plurality of energy storage capacitor devices respectively;

[0065] S4: The remote monitoring platform controls the main converter to start controlling the main converter, the slave converter and the energy storage capacitor in the energy storage capacitor to release electric energy, and at the same time, the remote monitoring platform displays the voltage waveform and current waveform at the output end of the main converter and the slave converter;

[0066] S5: After the test is completed, the control switch K2 is disconnected, and the remaining unconsumed electric energy in the energy storage capacitor device is released through the discharge resistor R.

[0067] In one or more embodiments of the present invention, the remote monitoring platform controls the main converter to start controlling the main converter and releasing electric energy from the converter and the energy storage capacitor in the energy storage capacitor device, specifically including the following steps:

[0068] S41: The first Buck module CNVTM1 in the main converter device sends a signal to the remaining Buck modules CNVTM2-CNVTMn in the main converter device and the Buck modules CNVTS1-CNVTSm in the slave converter device via the CAN bus according to the control signal of the remote monitoring platform, so that all Buck modules output synchronously;

[0069] S42: Each Buck branch generates a PWM wave signal according to the current signal and voltage signal collected by the corresponding branch current sensor and voltage sensor V1 respectively;

[0070] S43: The PWM wave signal drives the corresponding IGBT tube in the Buck branch to be turned on and off, so as to perform closed-loop control of the pulse current.

[0071] By controlling the remaining Buck modules CNVTM2-CNVTMn in the main converter and the Buck modules CNVTS1-CNVTSm in the slave converter through the first Buck module CNVTM1 in the main converter, the synchronous output of all Buck modules can be ensured, and a PWM wave signal is generated according to the current signal and voltage signal collected by the branch current sensor and the voltage sensor V1, thereby forming a closed-loop control of the pulse current and ensuring the stability of the pulse current.

[0072] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A pulse current output system based on Buck circuit, characterized in that: It includes a remote monitoring platform, a high-voltage power supply device, a main current conversion device, a slave current conversion device and a plurality of energy storage capacitor devices; The AC positive and negative output terminals of the high-voltage power supply device are electrically connected to the neutral terminal and the live terminal of the main converter device and the slave converter device respectively, the DC positive and negative output terminals of the high-voltage power supply device are electrically connected to the DC positive and negative input terminals of the main converter device, the slave converter device and each of the energy storage capacitor devices respectively, the positive output terminal of the main converter device is electrically connected to the positive output terminal of the slave converter device and serves as the output positive electrode of the pulse current, the negative output terminal of the high-voltage power supply device serves as the output negative electrode of the pulse current, the signal transceiver terminal of the main converter device is electrically connected to the signal transceiver terminal of the slave converter device respectively, and the data terminal of the remote monitoring platform is electrically connected to the data terminal of the high-voltage power supply device and the data terminal of the main converter device respectively; The remote monitoring platform is used to set input and output electrical parameters, and control the high-voltage power supply device to start or stop boosting the main converter device, the slave converter device and the energy storage capacitors in the multiple energy storage capacitor devices; The high-voltage power supply device is used to provide AC power to the main converter device, the slave converter device and the multiple energy storage capacitor devices respectively; and is also used to boost the voltage of the main converter device, the slave converter device and the energy storage capacitors in the multiple energy storage capacitor devices according to the control instructions of the remote monitoring platform; The remote monitoring platform is also used to send control instructions to the main converter device; The main inverter device is used to start or stop controlling the main inverter device, the slave inverter device and the energy storage capacitor in the energy storage capacitor device to release electric energy according to the control instructions of the remote monitoring platform, and is also used to control it to output pulse current synchronously with the slave inverter device, and is also used to communicate with the remote monitoring platform.

2. The pulse current output system based on Buck circuit according to claim 1, characterized in that: The main converter device includes a plurality of Buck modules CNVTM1-CNTVMn, parallel inductors LM1-LM 2n , voltage sensor V2, main current sensor, switch K2 and discharge resistor R, the DC positive and negative output terminals J2-1 and J2-2 of the high-voltage power supply device are respectively electrically connected to the DC positive and negative input terminals VIN+ and VIN- of the Buck modules CNVTM1-CNTVMn, and boost the energy storage capacitor in the Buck modules CNVTM1-CNTVMn, the neutral line terminal and the live line terminal of the high-voltage power supply device are respectively electrically connected to the neutral line terminal and the live line terminal of each Buck module CNVTM1-CNTVMn, and power the Buck modules CNVTM1-CNTVMn, the signal output terminals VOUT1 and VOUT2 of the Buck modules CNVTM1-CNTVMn are respectively electrically connected to the parallel inductors LM1 and LM2, the parallel inductors LM3 and LM4...parallel inductors LM 2n-1 and LM 2n The parallel inductors LM1 and LM2, the parallel inductors LM3 and LM4, and the parallel inductors LM 2n-1 and LM 2n The other end is respectively electrically connected to the pulse current output positive terminal J3-1, a switch K2 and a discharge resistor R are connected in series between the DC negative output end of the high-voltage power supply device and the pulse current output positive terminal J3-1, the voltage sensor V2 is electrically connected between the DC negative output end of the high-voltage power supply device and the pulse current output positive terminal J3-1, the pulse current output positive terminal J3-1 is electrically connected to the main current sensor, the data end LAN of the Buck module CNVTM1 is electrically connected to the data end of the remote monitoring platform, and the transceiver signal ends CAN-H and CAN-L of the Buck main modules CNVTM1-CNTVMn are electrically connected to the CAN bus terminals J4-1 and J4-2 respectively.

3. The pulse current output system based on Buck circuit according to claim 1, characterized in that: The slave converter includes a plurality of Buck modules CNVTS1-CNTVSm and parallel inductors LS1-LS 2m The DC positive and negative output terminals J2-1 and J2-2 of the high-voltage power supply device are respectively electrically connected to the DC positive and negative input terminals VIN+ and VIN- of each of the Buck modules CNVTS1-CNTVSm, and boost the energy storage capacitor in the Buck modules CNVTS1-CNTVSm. The neutral line terminal and the live line terminal of the high-voltage power supply device are respectively electrically connected to the neutral line terminal and the live line terminal of each of the Buck modules CNVTS1-CNTVSm, and supply power to the Buck modules CNVTS1-CNTVSm. The signal output terminals VOUT1 and VOUT2 of the Buck modules CNVTS1-CNTVSm are respectively electrically connected to the parallel inductors LS1 and LS2, the parallel inductors LS3 and LS4...the parallel inductors LS 2m-1 and LS 2m The parallel inductors LS1 and LS2, the parallel inductors LS3 and LS4, and the parallel inductors LS 2m-1 and LS 2m The other end is electrically connected to the pulse current output positive terminal J3-1 respectively, and the receiving and transmitting signal ends CAN-H and CAN-L of all the Buck modules CNVTS1-CNTVSm are electrically connected to the CAN bus terminals J4-1 and J4-2 respectively.

4. The pulse current output system based on Buck circuit according to claim 2 or 3, characterized in that: The Buck modules in the master converter and the slave converter each include a plurality of parallel Buck branches, a storage circuit C1 and a voltage sensor V1, and each of the Buck branches includes an IGBT module, each of the IGBT modules includes an upper bridge arm IGBT tube, a lower bridge arm IGBT tube, a branch current sensor, an absorption capacitor and a filter inductor, the collector of the upper bridge arm IGBT tube is used as a positive input terminal VIN+ and is electrically connected to the DC positive output terminal J2-1 of the high-voltage power supply device, and the emitter of the upper bridge arm IGBT tube and the collector of the lower bridge arm IGBT tube are respectively connected to the corresponding filter inductor. The corresponding branch current sensor is electrically connected between one end of the filter inductor and the other end of the filter inductor as the signal output terminal VOUT1 or VOUT2 and electrically connected to one end of the corresponding parallel inductor, the emitter of the lower bridge arm IGBT tube is electrically connected to the DC negative output terminal J2-2 of the high-voltage power supply device as the negative input terminal VIN-, the corresponding absorption capacitor is electrically connected between the collector of the upper bridge arm IGBT tube and the emitter of the lower bridge arm IGBT tube, and the voltage sensor V1 and the energy storage capacitor C1 are connected in parallel between the positive input terminal VIN+ and the negative input terminal VIN- of each Buck branch.

5. The pulse current output system based on Buck circuit according to any one of claims 1 to 4, characterized in that: The energy storage capacitor device includes a plurality of CAP modules and fuses having the same number and corresponding one to one with the CAP modules. The positive electrode of the CAP module is electrically connected to the DC positive output terminal J1-1 of the high-voltage power supply device through the corresponding fuse, and the negative electrode of the CAP module is electrically connected to the DC negative output terminal J1-2 of the high-voltage power supply device.

6. A method for outputting a pulse current based on a Buck circuit, which adopts the pulse current output system based on a Buck circuit according to any one of claims 1 to 5, characterized in that: The steps include: Set the preset ranges of input voltage, input current, output voltage and output current, and pulse current output time on the remote monitoring platform; The remote monitoring platform sends a control instruction to the high-voltage power supply device, controls the high-voltage power supply device to start providing AC power to the main converter device, the slave converter device and the multiple energy storage capacitor devices, and controls the high-voltage power supply device to start boosting the energy storage capacitors in the main converter device, the slave converter device and the multiple energy storage capacitor devices until the boosting of the energy storage capacitors is completed; The remote monitoring platform controls the high-voltage power supply device to stop providing AC power to the main converter device, the slave converter device and the plurality of energy storage capacitor devices respectively; The remote monitoring platform controls the main converter device to start controlling the main converter device, the slave converter device and the energy storage capacitor in the energy storage capacitor device to release electric energy, and at the same time, the remote monitoring platform displays the voltage waveform and current waveform at the output end of the main converter device and the slave converter device; After use, the control switch K2 is disconnected, and the remaining unconsumed electric energy in the energy storage capacitor device is released through the discharge resistor R.

7. The pulse current output method based on Buck circuit according to claim 6, characterized in that: The remote monitoring platform controls the main converter to start controlling the main converter and the converter and the energy storage capacitor in the energy storage capacitor device to release electric energy, specifically including the following steps: The first Buck module CNVTM1 in the main converter sends an output instruction to the remaining Buck modules CNVTM2-CNVTMn in the main converter and the Buck modules CNVTS1-CNVTSm in the slave converter via the CAN bus according to the control signal of the remote monitoring platform, so that all Buck modules output synchronously; Each Buck branch generates a PWM wave signal according to the current signal and voltage signal collected by the corresponding branch current sensor and voltage sensor V1 respectively; The PWM wave signal drives the corresponding IGBT tube in the Buck branch to turn on and off, so as to perform closed-loop control of the pulse current.

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