Inverter type high-voltage power supply control system and method

Abstract

The invention relates to the technical field of high-voltage power supply control, and discloses an inversion type high-voltage power supply control system and method.The system comprises a sampling module, a DSP control module, m FPGA control modules and m * n inversion modules, and m and n are positive integers; the sampling module is configured to sample the output voltage and current of the inversion module in real time to generate a sampling result; the DSP control module is configured to calculate and generate a PWM waveform through a proportional-integral method according to the sampling result; the FPGA control module is configured to process the PWM waveform output by the DSP control module according to a set phase shift angle between PWM of each inversion module to generate a plurality of pairs of phase dislocation PWM control waveforms; the inverter module is configured to act according to the phase dislocation PWM control waveform. According to the invention, a DSP + FPGA controller architecture is adopted, so that expansion of any number of inversion modules can be realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of high-voltage power supply control, and particularly relates to an inverter type high-voltage power supply control system and method. BACKGROUND

[0002] At present, the inverter type high-voltage power supply is becoming a new favorite in the field of high-voltage and high-power with its unique technical advantages. It realizes a substantial reduction in the volume of the transformer by virtue of high-frequency inverter technology, and successfully breaks through the barriers of ordinary power grids in high-voltage and high-power pulse output in combination with super capacitor energy storage technology. In comparison, the PSM (pulse skip modulation) technical scheme adopted by the traditional high-voltage power supply has increasingly prominent disadvantages in volume, process and power grid adaptability, and is difficult to meet the needs of modern industry for efficient and flexible power supply.

[0003] The inverter module is a core component of the inverter type high-voltage power supply, and its design directly affects the overall performance of the power supply. A single inverter module adopts the phase-shifted full-bridge soft switching technology, which has obvious advantages compared with the hard switching scheme. In the hard switching circuit, the power device is turned on when the voltage is not off or is broken when the current is not zero, which will generate huge switching loss and electromagnetic interference. The phase-shifted full-bridge soft switching adjusts the conduction phase difference of the four bridge arms, so that the power device completes the switching action in the zero voltage or zero current state, the switching loss is significantly reduced, the electromagnetic interference is also greatly reduced, and the stable and reliable operation of the high-voltage power supply is ensured.

[0004] In order to optimize the output quality, the staggered phase-shift control strategy is adopted between multiple inverter modules. When multiple modules work in parallel, different phase offsets are set, so that the output ripple of each module can be offset. In the high-voltage state, the excessive ripple will affect the output accuracy and may accelerate the aging of the insulation material and shorten the service life of the equipment, so this control strategy is crucial for the high-voltage power supply.

[0005] The normal operation of each inverter module cannot be separated from perfect signal interaction, and at least 4 optical fiber signals are needed. Among them, two PWM input signals are used to control the switching timing of the power device, one fault reset input signal is used to clear the protection state of the module, and one fault feedback output signal is used to report abnormal conditions such as overcurrent and overvoltage to the main control system. In the high-voltage environment, electromagnetic interference is very strong, and ordinary cable signal transmission is easy to distort, while optical fiber has the characteristics of anti-electromagnetic interference and low transmission loss, which can ensure stable transmission of signals within tens of meters and smooth communication between modules.

[0006] The output voltage of a high-voltage power supply is closely related to the number of inverter modules. When using a series stacking method, the total output voltage is equal to the output voltage of a single module multiplied by the number of modules. A 120kV inverter-type high-voltage power supply typically requires 128 modules in series, which requires 512 fiber optic signal channels. As the voltage level increases, the number of modules increases linearly, and as the voltage continues to rise, more inverter modules are required.

[0007] However, traditional DSP chip solutions struggle to cope with this massive number of signals. Ordinary DSP chips typically have no more than 16 PWM output channels, and even with external expansion chips, this can only be expanded to 64 channels at most. Furthermore, this expansion process can lead to inconsistent signal delays and reduced synchronization accuracy. For example, after the PWM signal undergoes multi-stage expansion, the switching actions of different modules may experience microsecond-level phase deviations. In a multi-module system connected in series, this can lead to uneven voltage distribution, causing individual modules to experience voltages exceeding their rated values, potentially causing breakdown failures. Summary of the Invention

[0008] In order to solve the above problems, the present invention proposes an inverter-type high-voltage power supply control system and method, which adopts a DSP+FPGA controller architecture, can realize the expansion of any number of inverter modules, and adopts phase-shifted full-bridge soft switching technology and multi-module interleaved shifting technology, which has important application significance.

[0009] The technical solution adopted in the present invention is as follows: An inverter-type high-voltage power supply control system includes a sampling module, a DSP control module, m FPGA control modules, and m*n inverter modules, where m and n are both positive integers; The sampling module is configured to sample the output voltage and current of the inverter module in real time and generate sampling results; The DSP control module is configured to calculate and generate a PWM waveform using a proportional-integral method according to the sampling result; The FPGA control module is configured to process the PWM waveform output by the DSP control module according to the set phase shift angle between the PWMs of each inverter module to generate a plurality of staggered phase PWM control waveforms; The inverter module is configured to operate according to the staggered PWM control waveform.

[0010] Furthermore, the inverter module includes an input rectifier circuit, a pre-charging circuit, a high-frequency inverter circuit, a high-frequency transformer and a high-frequency output rectifier circuit; the input end of the input rectifier circuit is connected to the AC power grid or a supercapacitor, and the output end is connected to the input end of the pre-charging circuit, and the output end of the pre-charging circuit is connected to the input end of the high-frequency inverter circuit; the output end of the high-frequency inverter circuit is connected to the primary side of the high-frequency transformer, and the secondary side of the high-frequency transformer is connected to the input end of the high-frequency output rectifier circuit; the positive pole of the high-frequency output rectifier circuit serves as the positive output end of the inverter module, and the negative pole serves as the negative output end of the inverter module.

[0011] Furthermore, the input rectifier circuit is configured to convert alternating current into direct current and filter out high-frequency noise in the alternating current.

[0012] Furthermore, the input rectifier circuit includes a full-bridge uncontrolled rectifier circuit.

[0013] Furthermore, the pre-charging circuit is configured to charge the DC bus capacitor through the current limiting resistor when the system is started, and short-circuit the current limiting resistor through the relay after charging is completed.

[0014] Furthermore, the high-frequency inverter circuit is configured to perform high-frequency switching based on an over-phase-shifted control technology and an out-of-phase PWM control waveform output by an FPGA control module.

[0015] Furthermore, the high-frequency inverter circuit includes a full-bridge inverter topology circuit composed of high-frequency switching devices.

[0016] Furthermore, the high-frequency transformer is configured to perform voltage conversion on high-frequency alternating current and achieve electrical isolation between input and output; the high-frequency transformer includes a high-frequency magnetic core and windings.

[0017] Furthermore, the high-frequency output rectifier circuit is configured to convert high-frequency alternating current into direct current, and the high-frequency output rectifier circuit includes a high-frequency rectifier diode, a filter capacitor, and an inductor.

[0018] A method for controlling an inverter-type high-voltage power supply, comprising: The output voltage and current of the inverter module are sampled in real time through the sampling module to generate sampling results; Based on the sampling results, a PWM waveform is calculated and generated by a DSP control module according to a proportional-integral method; Based on the set phase shift angle between the PWM of each inverter module, the FPGA control module processes the PWM waveform output by the DSP control module to generate several pairs of staggered phase PWM control waveforms, thereby driving and controlling the inverter module.

[0019] The beneficial effects of the present invention are: 1. This invention utilizes high-frequency inverter technology, significantly reducing the size of the transformer. Combined with supercapacitor energy storage technology, it enables high-voltage, high-power pulse output under standard grid power conditions. This invention employs a DSP+FPGA control architecture, resolving the limitations of conventional DSP solutions in high-voltage inverter applications, which limit the number of PWM output paths and hinder scalability.

[0020] 2. This invention utilizes phase-shifted full-bridge soft switching technology and multi-module interleaved shifting technology. By properly designing the phase shift angle, some low-order harmonics can cancel each other out, significantly reducing the harmonic content in the output voltage. Furthermore, phase shift control increases the number of switching tube operations, thereby increasing the equivalent switching frequency and effectively suppressing output ripple. With phase shift control, the filter only needs to process the remaining small amount of high-frequency harmonics, allowing the use of smaller filter capacitors and inductors to achieve better filtering effects and further reduce output ripple. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a block diagram of an inverter-type high-voltage power supply control system according to embodiment 1 of the present invention.

[0022] Figure 2 This is a schematic diagram of an inverter-type high-voltage power supply control system according to embodiment 1 of the present invention.

[0023] Figure 3 This is a schematic circuit diagram of an inverter module according to embodiment 1 of the present invention.

[0024] Figure numerals: 1-input rectifier circuit, 2-precharge circuit, 3-high-frequency inverter circuit, 4-high-frequency transformer, 5-high-frequency output rectifier circuit. DETAILED DESCRIPTION

[0025] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, the specific embodiments of the present invention are now described. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. That is, the embodiments described are only part of the embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present invention.

[0026] Example 1 like Figure 1 and Figure 2As shown, this embodiment provides an inverter-type high-voltage power supply control system, comprising a sampling module, a DSP control module, m FPGA control modules, and m*n inverter modules, where m and n are both positive integers. The sampling module is configured to sample the output voltage and current of the inverter modules in real time and generate sampling results; the DSP control module is configured to calculate and generate PWM waveforms based on the sampling results using a proportional-integral method; and the FPGA control module is configured to process the PWM waveforms output by the DSP control module based on the set phase shift angles between the PWMs of each inverter module, generating a plurality of staggered-phase PWM control waveforms to drive and control the high-frequency power devices in the high-frequency inverter circuits of each inverter module.

[0027] Preferably, if Figure 3 As shown, the inverter module includes an input rectifier circuit, a pre-charging circuit, a high-frequency inverter circuit, a high-frequency transformer and a high-frequency output rectifier circuit; the input terminal of the input rectifier circuit is connected to the AC power grid or a supercapacitor, and the output terminal is connected to the input terminal of the pre-charging circuit, and the output terminal of the pre-charging circuit is connected to the input terminal of the high-frequency inverter circuit; the output terminal of the high-frequency inverter circuit is connected to the primary side of the high-frequency transformer, and the secondary side of the high-frequency transformer is connected to the input terminal of the high-frequency output rectifier circuit; the positive electrode of the high-frequency output rectifier circuit serves as the positive output terminal of the inverter module, and the negative electrode serves as the negative output terminal of the inverter module.

[0028] In this embodiment, the input rectifier circuit is configured to convert AC power into DC power and filter out high-frequency noise in the AC power. Preferably, the input rectifier circuit can be implemented using a full-bridge uncontrolled rectifier circuit.

[0029] The pre-charging circuit is configured to slowly charge the DC bus capacitor through a current-limiting resistor when the system starts. After charging is completed, the current-limiting resistor is short-circuited by a relay to avoid instantaneous high current shock and protect circuit components.

[0030] The high-frequency inverter circuit is configured to achieve high-frequency switching based on over-phase control technology, reducing energy loss and improving efficiency. Preferably, the high-frequency inverter circuit can adopt a full-bridge inverter topology circuit composed of high-frequency switching devices (such as MOSFETs and IGBTs).

[0031] A high-frequency transformer is configured to convert the voltage of high-frequency alternating current (stepping it up or down) and achieve electrical isolation between the input and output, improving system safety. Preferably, the high-frequency transformer can be implemented using a high-frequency magnetic core (such as ferrite) and windings.

[0032] The high-frequency output rectifier circuit is configured to convert high-frequency alternating current into direct current, providing a stable direct current power supply to the load. Preferably, the high-frequency output rectifier circuit can use a high-frequency rectifier diode in combination with a filter capacitor and an inductor to reduce output ripple.

[0033] Preferably, each inverter module requires at least four fiber optic signals: two PWM inputs, one fault reset input, and one fault feedback output. The two PWMs are used to control the inverter module's operating phase shift angle, thereby achieving different voltage outputs; the fault reset input is used to reset inverter module faults; and the fault feedback output is used to detect inverter module faults.

[0034] Specifically, if Figure 2 As shown, the phase-shifted PWM waveform output by the DSP control module is divided into four channels, each of which is connected to four FPGA control modules. Each FPGA control module contains 128 I / O outputs. Each inverter module requires four I / O signals: two PWM inputs, one fault reset input, and one fault feedback output. Therefore, a single FPGA control module can perform staggered phase control for up to 32 inverter modules. The system supports up to 128 pairs of PWM outputs, allowing for simultaneous staggered phase control of 12 inverter modules. Each inverter module is connected in series to ultimately output high-voltage inverter power.

[0035] It's important to note that each pair of PWM signals has the same internal phase-shift angle. This angle is determined by the PWM waveform pairs generated by the DSP control module and is used to adjust the output voltages of each inverter module. The phase-shift angle between each PWM pair can be arbitrarily set based on the number of output modules, allowing for staggered phase control between inverter modules to reduce output ripple. For example, with 128 pairs of PWM outputs, each pair can be staggered by 180 / 128 = 1.4 degrees relative to the previous pair.

[0036] In summary, this system utilizes high-frequency inverter technology to significantly reduce the size of the transformer, resolving the limitations of conventional DSP solutions in terms of limited PWM output paths and difficulty in scalability. Furthermore, this system utilizes phase-shifted full-bridge soft-switching technology and multi-module interleaved shifting. By properly designing the phase shift angle, this significantly reduces the harmonic content in the output voltage, increases the equivalent switching frequency, effectively suppresses output ripple, and reduces the burden on the output filter.

[0037] Example 2 This embodiment is based on embodiment 1: This embodiment provides an inverter-type high-voltage power supply control method, including: The output voltage and current of the inverter module are sampled in real time through the sampling module to generate sampling results; Based on the sampling results, a PWM waveform is calculated and generated by a DSP control module according to a proportional-integral method; Based on the set phase shift angle between the PWM of each inverter module, the FPGA control module processes the PWM waveform output by the DSP control module to generate several pairs of staggered phase PWM control waveforms, thereby driving and controlling the inverter module.

[0038] It should be noted that, for the aforementioned method embodiments, for the sake of simplicity of description, they are expressed as a series of action combinations, but those skilled in the art should be aware that this application is not limited by the order of the actions described, because according to this application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by this application. It should also be noted that, unless otherwise clearly specified and limited, the terms "setting", "installation" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a wired connection or a wireless connection.

[0039] The foregoing description is merely a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein and should not be construed as excluding other embodiments. Rather, the present invention can be used in various other combinations, modifications, and environments and can be modified within the scope of the concept described herein through the above teachings or techniques or knowledge in the relevant field. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention are intended to be protected by the appended claims.

Claims

1. An inverter-type high-voltage power supply control system, characterized in that: It includes a sampling module, a DSP control module, m FPGA control modules and m*n inverter modules, where m and n are both positive integers; The sampling module is configured to sample the output voltage and current of the inverter module in real time and generate sampling results; The DSP control module is configured to calculate and generate a PWM waveform using a proportional-integral method according to the sampling result; The FPGA control module is configured to process the PWM waveform output by the DSP control module according to the set phase shift angle between the PWMs of each inverter module to generate a plurality of staggered phase PWM control waveforms; The inverter module is configured to operate according to the staggered PWM control waveform.

2. The inverter-type high-voltage power supply control system according to claim 1, characterized in that: The inverter module includes an input rectifier circuit, a pre-charging circuit, a high-frequency inverter circuit, a high-frequency transformer, and a high-frequency output rectifier circuit; the input terminal of the input rectifier circuit is connected to the AC power grid or a supercapacitor, and the output terminal is connected to the input terminal of the pre-charging circuit, and the output terminal of the pre-charging circuit is connected to the input terminal of the high-frequency inverter circuit; the output terminal of the high-frequency inverter circuit is connected to the primary side of the high-frequency transformer, and the secondary side of the high-frequency transformer is connected to the input terminal of the high-frequency output rectifier circuit; the positive electrode of the high-frequency output rectifier circuit serves as the positive output terminal of the inverter module, and the negative electrode serves as the negative output terminal of the inverter module.

3. The inverter-type high-voltage power supply control system according to claim 2, characterized in that: The input rectifier circuit is configured to convert alternating current (AC) into direct current (DC) and filter out high-frequency noise in the AC.

4. The inverter-type high-voltage power supply control system according to claim 2, characterized in that: The input rectifier circuit includes a full-bridge uncontrolled rectifier circuit.

5. The inverter-type high-voltage power supply control system according to claim 2, characterized in that: The pre-charging circuit is configured to charge the DC bus capacitor through the current limiting resistor when the system starts, and short-circuit the current limiting resistor through the relay after charging is completed.

6. The inverter-type high-voltage power supply control system according to claim 2, characterized in that: The high-frequency inverter circuit is configured to perform high-frequency switching based on an over-phase-shifted control technology according to a staggered-phase PWM control waveform output by an FPGA control module.

7. The inverter-type high-voltage power supply control system according to claim 2, characterized in that: The high-frequency inverter circuit includes a full-bridge inverter topology circuit composed of high-frequency switching devices.

8. The inverter-type high-voltage power supply control system according to claim 2, characterized in that: The high-frequency transformer is configured to perform voltage conversion on high-frequency alternating current and achieve electrical isolation between input and output; the high-frequency transformer includes a high-frequency magnetic core and a winding.

9. The inverter-type high-voltage power supply control system according to claim 2, characterized in that: The high-frequency output rectifier circuit is configured to convert high-frequency alternating current into direct current. The high-frequency output rectifier circuit includes a high-frequency rectifier diode, a filter capacitor, and an inductor.

10. A method for controlling an inverter-type high-voltage power supply, characterized in that: include: The output voltage and current of the inverter module are sampled in real time through the sampling module to generate sampling results; Based on the sampling results, a PWM waveform is calculated and generated by a DSP control module according to a proportional-integral method; Based on the set phase shift angle between the PWM of each inverter module, the FPGA control module processes the PWM waveform output by the DSP control module to generate several pairs of staggered phase PWM control waveforms, thereby driving and controlling the inverter module.

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