High-voltage direct-current power supply and power system

Abstract

The invention provides a high-voltage direct-current power supply and a power system, and relates to the technical field of power. The high-voltage direct-current power supply comprises N parallel HVDC modules which are electrically connected with an alternating-current power supply, are electrically connected with a load through a direct-current bus and are used for supplying power to the load; each HVDC module comprises a first branch circuit, a second branch circuit and a third branch circuit, wherein the first branch circuit comprises a rectifier and a first DC / DC converter which are connected in series and is used for converting and stabilizing alternating current output by an alternating current power supply into first direct current; the second branch comprises a direct current energy storage device and a second DC / DC converter which are connected in series, and is used for converting and stabilizing the direct current output by the direct current energy storage device into a second path of direct current in the discharge mode; the first connection point is used for connecting the output end of the first branch and the output end of the second branch in parallel, and the first direct current and the second direct current are superposed at the first connection point to serve as the output direct current of the HVDC module. According to the scheme, the N HVDC modules are connected in parallel, and uninterrupted operation of the system is guaranteed.

Description

Technical Field

[0001] This disclosure relates to the field of power technology, and more specifically, to a high-voltage direct current power supply and a power system. Background Technology

[0002] As AI continues to develop, chip power has increased from hundreds of watts to thousands of watts, and single-rack power has increased from tens of kilowatts to hundreds of kilowatts, or even megawatt-level racks. This presents many challenges for rack power supply, such as the need for more PDUs (Power Distribution Units) and more cables for power distribution paths. Traditional 240V DC power supplies (High Voltage Direct Current, HVDC) are insufficient to power ultra-high power density racks. Summary of the Invention

[0003] This disclosure provides a high-voltage DC power supply and a power system that at least partially overcomes the technical problem that traditional high-voltage DC power supplies in related technologies cannot meet the power supply requirements of ultra-high power density cabinets.

[0004] According to a first aspect of the present disclosure, a high-voltage DC power supply is provided, comprising: N parallel HVDC modules, each having an input terminal electrically connected to an AC power source and an output terminal electrically connected to a load via a DC bus, for providing DC power to the load, where N is an integer greater than or equal to 1; each HVDC module comprising: a first branch including a rectifier and a first DC / DC (Direct Current / Direct Current) converter connected in series, for converting and stabilizing the AC power output from the AC power source into a first DC power source; a second branch including a DC energy storage device and a second DC / DC converter connected in series, for converting and stabilizing the DC power output from the DC energy storage device into a second DC power source in a discharge mode; and a first connection point for connecting the output terminals of the first branch and the second branch in parallel, such that the first DC power source and the second DC power source are superimposed at the first connection point and jointly serve as the output DC power of the HVDC module.

[0005] In some embodiments, the second DC / DC converter is a bidirectional DC / DC converter.

[0006] In some embodiments, a second DC / DC converter is used to convert a portion of the first DC power supply into a voltage adapted to the DC energy storage device in charging mode, thereby charging the DC energy storage device.

[0007] In some embodiments, the second DC / DC converter includes: a first transistor, a second transistor, a third transistor, a fourth transistor, a first capacitor, a second capacitor, and a first inductor; the first capacitor is connected in parallel with a DC energy storage device, the positive terminal of the second capacitor is electrically connected to a first connection point, and the negative terminal of the second capacitor is grounded; the first terminal of the first transistor is electrically connected to the positive terminal of the DC energy storage device, the second terminal of the first transistor is electrically connected to the first terminal of the second transistor, and the second terminal of the second transistor is grounded; the first terminal of the third transistor is electrically connected to the first connection point, the second terminal of the third transistor is electrically connected to the first terminal of the fourth transistor, and the second terminal of the fourth transistor is grounded; the second terminal of the first transistor is electrically connected to the second terminal of the third transistor through the first inductor.

[0008] In some embodiments, the DC energy storage device includes L groups of battery packs connected in parallel, where L is an integer greater than or equal to 1.

[0009] In some embodiments, the battery pack includes a lithium battery pack.

[0010] In some embodiments, each HVDC module includes M parallel first branches, where M is an integer greater than or equal to 1.

[0011] In some embodiments, the first branch further includes: a first diode, the positive terminal of which is electrically connected to the output terminal of the first DC / DC converter, and the negative terminal of which is electrically connected to the first connection point.

[0012] In some embodiments, the rectifier is a three-phase PWM (Pulse width modulation) rectifier, and each phase rectifier includes: two parallel interleaved single-phase PFC (Power Factor Correction) units; wherein, the phase difference of the PWM signals of any two phase rectifiers is a first angle, and the phase difference of the PWM signals of the two PFC units in each phase rectifier is a second angle.

[0013] In some embodiments, the first DC / DC converter includes a switching network, a resonant network, and a rectifier filter network connected in sequence.

[0014] In some embodiments, the system further includes a controller electrically connected to the rectifier, the first DC / DC converter, and the second DC / DC converter, respectively, for controlling the high-voltage DC power supply to switch between multiple operating modes.

[0015] The high-voltage DC power supply provided in this embodiment includes: N parallel HVDC modules, whose input terminals are electrically connected to an AC power source, and whose output terminals are electrically connected to a load via a DC bus, for providing DC power to the load, where N is an integer greater than or equal to 1; each HVDC module includes: a first branch, including a rectifier and a first DC / DC / DC converter connected in series, for converting and stabilizing the AC power output from the AC power source into a first DC power source; a second branch, including a DC energy storage device and a second DC / DC converter connected in series, for converting and stabilizing the DC power output from the DC energy storage device into a second DC power source in discharge mode; and a first connection point for connecting the output terminals of the first branch and the second branch in parallel, so that the first DC power source and the second DC power source are superimposed at the first connection point and jointly serve as the output DC power of the HVDC module. In this scheme, the parallel connection of N HVDC modules saves space, facilitates heat dissipation, supports redundant configuration, and allows other HVDC modules to immediately take over if any HVDC module fails, ensuring uninterrupted system operation. DC energy storage devices achieve stable output voltage during battery discharge by using internal DC / DC regulation of the HVDC module and then connecting it in parallel to the total output.

[0016] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0017] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure. It is obvious that the drawings described below are merely some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0018] Figure 1 This is a structural block diagram of a high-voltage DC power supply according to an exemplary embodiment.

[0019] Figure 2 This is a structural block diagram of another high-voltage DC power supply according to an exemplary embodiment.

[0020] Figure 3 This is a structural block diagram of another high-voltage DC power supply according to an exemplary embodiment.

[0021] Figure 4 This is a circuit topology diagram of a high-voltage DC power supply according to an exemplary embodiment.

[0022] Figure 5 This is a circuit topology diagram of another high-voltage DC power supply according to an exemplary embodiment.

[0023] Figure 6 This is a circuit topology diagram of another high-voltage DC power supply according to an exemplary embodiment.

[0024] Figure 7 This is a circuit topology diagram of another high-voltage DC power supply according to an exemplary embodiment.

[0025] Figure 8 This is a circuit topology diagram of another high-voltage DC power supply according to an exemplary embodiment.

[0026] Figure 9 This is a structural block diagram of another high-voltage DC power supply according to an exemplary embodiment. Detailed Implementation

[0027] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar parts, and therefore repeated descriptions of them will be omitted.

[0028] The features, structures, or characteristics described in this disclosure can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a thorough understanding of embodiments of this disclosure. However, those skilled in the art will recognize that the technical solutions of this disclosure can be practiced with one or more specific details omitted, or other methods, components, apparatuses, steps, etc., can be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this disclosure.

[0029] The accompanying drawings are merely illustrative of this disclosure, and the same reference numerals in the drawings denote the same or similar parts, thus omitting repeated descriptions of them. Some block diagrams shown in the drawings do not necessarily correspond to physically or logically independent entities. These functional entities may be implemented in software, in at least one hardware module or integrated circuit, or in different network and / or processor devices and / or microcontroller devices.

[0030] The flowchart shown in the accompanying drawings is merely illustrative and does not necessarily include all content and steps, nor does it require execution in the described order. For example, some steps may be broken down, while others may be combined or partially combined; therefore, the actual execution order may change depending on the specific circumstances.

[0031] In this specification, the terms “a,” “an,” “the,” “the,” and “at least one” are used to indicate the presence of at least one element / component / etc.; the terms “comprising,” “including,” and “having” are used to indicate an open-ended inclusion and to mean that there may be other elements / components / etc. in addition to the listed elements / components / etc.; the terms “first,” “second,” and “third,” etc., are used only as markings and are not a limitation on the number of objects.

[0032] Figure 1 A schematic diagram of a high-voltage DC power supply according to an embodiment of this disclosure is shown, as follows: Figure 1 As shown, the high-voltage DC power supply 10 includes: N parallel HVDC modules 100, whose input terminals are electrically connected to the AC power supply 20, and whose output terminals are electrically connected to the load 30 via a DC bus, for providing DC power to the load 30, where N is an integer greater than or equal to 1; each HVDC module 100 includes: a first branch 110, including a rectifier 111 and a first DC / DC converter 112 connected in series, for converting and stabilizing the AC power output from the AC power supply into a first DC power; a second branch 120, including a DC energy storage device 122 and a second DC / DC converter 121 connected in series, for converting and stabilizing the DC power output from the DC energy storage device 122 into a second DC power in discharge mode; and a first connection point 130, for connecting the output terminals of the first branch and the second branch in parallel, so that the first DC power and the second DC power are superimposed at the first connection point 130 and together serve as the output DC power of the HVDC module.

[0033] A high-voltage direct current (HVDC) power supply is a power protection device that provides a continuous, stable, and high-quality uninterrupted power supply to a load. For example, internet data centers extensively utilize HVDC. In this embodiment, the HVDC power supply comprises N HVDC modules that can operate in parallel. Its capacity can be flexibly configured through modular design. This HVDC power supply includes multiple operating modes, such as AC power supply, battery power supply, and combined power supply. Loads include, but are not limited to, computers, servers, network equipment, medical instruments, and industrial control systems.

[0034] An AC power source refers to an external power supply device or system capable of providing sinusoidal alternating current, used to provide standard sinusoidal alternating current. For example, an AC power source can be a public power grid, also known as mains power or grid power. Furthermore, an AC power source can also include: an AC generator driven by an internal combustion engine, a renewable energy power generation system, etc., such as a grid-connected photovoltaic inverter or a wind power inverter.

[0035] HVDC module 100 is the basic unit of high voltage DC power supply. Each HVDC module includes a complete and independent first branch and second branch. Each HVDC module is connected in parallel through the output terminal and then connected to the DC bus. The DC bus supplies power to the load to achieve power expansion and redundancy backup.

[0036] like Figure 1 As shown, the first branch 110 is the path in the HVDC module 100 used to process AC power. It is composed of a rectifier 111 and a first DC / DC converter 112 connected in series, and is used to convert AC power into DC power and regulate the voltage.

[0037] Specifically, rectifier 111 is used to convert the AC power input from AC power source 20 into DC power. For example, depending on the actual application requirements, rectifier 111 can be designed with different topologies, including but not limited to: a three-phase six-switch full-bridge rectifier, a three-phase Vienna rectifier, etc.

[0038] The input of the first DC / DC converter 112 receives the DC power output from the rectifier 111, and through high-frequency switches, magnetic components (inductors, transformers), and capacitors, transforms and regulates its voltage to output a regulated first-path DC power. For example, the first-path DC power is a stable 800V DC power, unaffected by fluctuations in the front-end AC voltage. The first DC / DC converter 112 includes, but is not limited to, isolated LLC resonant converters, phase-shifted full-bridge converters, etc.

[0039] The second branch 120 is the path in the HVDC module 100 used for energy storage device access and DC conversion. It is composed of DC energy storage device 122 and second DC / DC converter 121 connected in series. It is used to decouple the voltage output by DC energy storage device from DC bus voltage through DC / DC converter, so as to avoid voltage fluctuation on DC bus caused by direct connection of battery to bus.

[0040] Specifically, the DC energy storage device 122 is a DC source device for storing electrical energy. The DC energy storage device can be a battery or battery pack, or a supercapacitor or other type of DC energy storage system. For example, the DC energy storage device is a lithium battery pack that outputs a DC voltage of 700-800V, allowing the DC bus voltage to reach 800V.

[0041] In some embodiments, the second DC / DC converter 121 is a bidirectional DC / DC converter.

[0042] A bidirectional DC / DC converter can achieve bidirectional energy flow between two connected DC ports according to control commands. In this embodiment, a second DC / DC converter 121 is connected between the DC energy storage device 122 and the first connection point 130. The second DC / DC converter 121 controls the on and off of its internal power switching transistors according to control commands, and, together with its internal passive components such as inductors and capacitors, constructs two energy flow paths.

[0043] In one possible implementation, the second DC / DC converter 121 includes two operating modes: a discharge mode and a charging mode. In discharge mode, current flows from the DC energy storage device 122 to the first connection point 130. In discharge mode, the second DC / DC converter 121 can be considered a boost converter, used to boost and stabilize the DC power supplied by the DC energy storage device 122 to the constant high voltage required by the load, serving as a second DC power source. Even as the voltage of the DC energy storage device 122 decreases with the duration of discharge, the voltage output from the second DC / DC converter 121 to the first connection point 130 (DC bus) remains stable.

[0044] In some embodiments, the second DC / DC converter is used to convert a portion of the first DC power supply into a voltage adapted to the DC energy storage device in charging mode, thereby charging the DC energy storage device.

[0045] The second DC / DC converter 121 operates in charging mode, with current flowing from the first connection point 130 to the DC energy storage device 122. In charging mode, the second DC / DC converter 121 can be considered as a buck converter, used to reduce the stable high voltage of 800V from the first connection point 130 to a lower voltage required by the charging curve of the DC energy storage device, in order to charge the DC energy storage device 122.

[0046] For example, the second DC / DC converter 121 can be a non-isolated converter. For instance, in situations where electrical isolation is not required, the second DC / DC converter 121 can be a bidirectional Buck-Boost converter. In situations where electrical isolation between the input and output sides is required, the second DC / DC converter 121 can be an isolated converter, such as a bidirectional phase-shifted full-bridge converter or a bidirectional CLLC resonant converter, to improve the safety and anti-interference capability of the high-voltage DC power supply.

[0047] The first connection point 130 is an electrical node inside the HVDC100 module; in other words, the first connection point 130 can be understood as a power combiner point. The output terminals of the first branch 110 and the second branch 120 are directly connected in parallel to form a unified output interface, so as to realize the superposition of the first DC power and the second DC power.

[0048] In one application example, the 800V high-voltage DC power supply adopts a modular design, with the power of a single HVDC module reaching 60kW. The module adopts an N+X design. Taking a single cabinet of 600kW as an example, it generally uses 12 30kW modules in a 10+2 configuration, of which 10 modules are used as the main modules and 2 modules are used as backup modules.

[0049] In this embodiment, the high-voltage DC power supply operates in three main modes: AC power supply mode, battery power supply mode, and combined power supply mode.

[0050] In the combined power supply mode, the first branch 110 outputs a first 800V DC power at maximum capacity, while simultaneously controlling the second branch 120 to start and output a second 800V DC power. The first and second DC power supplies are DC power with equal voltage, and their currents are superimposed at the first electrical connection point 130. According to Kirchhoff's Current Law (KCL), the total output current at the first electrical connection point 130 is the sum of the currents of the first and second DC power supplies, thus achieving the superposition of total output power. In other words, in the combined power supply mode, the AC power supply and the DC energy storage device simultaneously supply power to the load.

[0051] In AC power supply mode, AC power from AC power source 20 flows into each HVDC module 100. In the first branch 110, the power passes through rectifier 111 and first DC / DC converter 112 in sequence, and outputs a stable first 800V DC power. After the first DC power reaches the first electrical connection point 130, it splits into two paths: one path serves as the output of the HVDC module and flows into the DC bus to power the load 30; the other path flows into the second branch 120, where the second DC / DC converter 121 operates in charging mode to convert the 800V bus voltage into a voltage that conforms to the battery charging curve of the DC energy storage device 122, thereby charging the DC energy storage device 122.

[0052] In battery-powered mode, the DC energy storage device 122 begins to discharge, converting its stored chemical energy into DC electrical energy, which is then input into the second DC / DC converter 121. The second DC / DC converter 121 operates in discharge mode and, through closed-loop control, ignores the gradual decrease in battery voltage due to discharge. It continuously boosts and stabilizes the changing voltage output from the DC energy storage device 122 at 800V, and outputs a stable second 800V DC power. The second 800V DC power is output through the first electrical connection point 130, replacing the first branch, and providing a stable voltage supply to the load 30 to solve the voltage fluctuation caused by the DC bus voltage dropping with the battery charge in traditional direct-connection battery schemes.

[0053] In one possible implementation, due to the use of time-of-use pricing in some areas, the electricity price varies at different times. During periods of low electricity prices (e.g., at night), the DC energy storage device 122 is charged through the first branch 110 to store low-priced electricity; during periods of high electricity prices (e.g., during peak hours when electricity demand is high), even if the AC grid is normal, the stored low-priced electricity can be discharged through the second branch to supply power to the load 30, thereby reducing electricity costs.

[0054] Furthermore, when load power demand rapidly increases and exceeds a preset power threshold, the high-voltage DC power supply is controlled to operate in a combined power supply mode. This involves controlling the second branch 120 and the first branch 110 of one or more HVDC modules to discharge simultaneously, jointly supplying power to the load. By using the discharge of the DC energy storage device to fill the power gap in the AC grid supply, the peak power drawn from the grid can be reduced to below a preset power threshold. This avoids an increase in the basic electricity price for the entire billing cycle due to short-term extremely high power demand, thereby reducing electricity costs.

[0055] In this solution, N HVDC modules are connected in parallel, which saves space, facilitates heat dissipation, and supports redundant configuration. If any HVDC module fails, the other HVDC modules can immediately take over, ensuring uninterrupted system operation. The DC energy storage device uses internal DC / DC regulation within the HVDC modules before being connected in parallel to the total output, ensuring stable output voltage even during battery discharge.

[0056] exist Figure 1 In the illustrated high-voltage direct current (HVDC) power supply topology, each HVDC module 100 includes one first branch and one second branch, meaning the number of first branches 110 and second branches 120 is the same. In some embodiments, each HVDC module includes M parallel first branches, where M is an integer greater than or equal to 1. Figure 2 As shown, each HVDC module includes three parallel first branches and one second branch; this is illustrated using an M=3 value as an example. It should be noted that... Figure 2The example provided is an uninterruptible power supply consisting of one HVDC module, and does not limit the number of HVDC modules.

[0057] In some possible implementations, each HVDC module 100 includes M parallel first branches 110, where M is an integer greater than or equal to 1. Each first branch 110 is identical and independent in electrical structure and function, and each includes a rectifier 111 and a first DC / DC converter 112.

[0058] The AC input terminals of the first branch 110 of M are all connected to the AC power supply 20, and their DC output terminals are all connected to the first connection point 130 inside the HVDC module.

[0059] In the technical solution of this embodiment, in a topology of N HVDC modules connected in parallel, each HVDC module includes M first branches 110 composed of a rectifier 111 and a first DC / DC converter 112 connected in series. When a fault occurs in a certain first branch, the fault is confined to the HVDC module, causing only a decrease in the rated power of the HVDC module, without causing the entire HVDC module to fail completely. The remaining (M-1) normal first branches in the HVDC module can continue to work, improving the stability of the high voltage DC power supply.

[0060] Based on the above embodiments, this disclosure optimizes the high-voltage DC power supply, primarily focusing on the DC energy storage device in the second branch. In some embodiments, the DC energy storage device includes L groups of parallel battery packs, where L is an integer greater than or equal to 1. The battery packs include lithium battery packs.

[0061] In this embodiment, the DC energy storage device consists of L parallel battery packs, where L is an integer greater than or equal to 1. Each battery pack is a physically and electrically independent energy storage unit. Figure 3 As shown, the DC energy storage device 122, which includes four battery packs, will be used as an example for illustration.

[0062] The L parallel lithium battery packs share a common output terminal connected to the input terminal of the second DC / DC converter 121. Therefore, the second DC / DC converter 121 processes the total current collected from all the parallel battery packs. In other words, in the second branch 120 of the HVDC module, the energy storage element consists of L independently manageable battery modules connected in parallel. According to the principle of parallel circuits, the L parallel battery packs can provide a larger total discharge current, thereby meeting the high power requirements of the high-voltage DC power supply in combined power supply mode or during instantaneous high-current discharge.

[0063] Furthermore, the battery pack is preferably a lithium battery pack, including but not limited to: lithium iron phosphate battery packs, ternary lithium battery packs, etc.

[0064] In this embodiment, by designing the DC energy storage device to consist of L sets of parallel lithium battery packs, the output capability and reliability of the high-voltage DC power supply are improved.

[0065] Based on the above embodiments, this disclosure provides a specific circuit structure for an HVDC module, such as... Figure 4 As shown, this circuit topology mainly describes the second DC / DC converter 121. Figure 4 As shown, the second DC / DC converter 121 includes: a first transistor M1, a second transistor M2, a third transistor M3, a fourth transistor M4, a first capacitor C1, a second capacitor C2, and a first inductor L1; the first capacitor C1 is connected in parallel with the DC energy storage device; the first terminal of the first transistor M1 is electrically connected to the positive terminal DC+ of the DC energy storage device, the second terminal of the first transistor M1 is electrically connected to the first terminal of the second transistor M2, and the second terminal of the second transistor M2 is grounded; the first terminal of the third transistor M3 is electrically connected to the first connection point 130, the second terminal of the third transistor M3 is electrically connected to the first terminal of the fourth transistor M4, and the second terminal of the fourth transistor M4 is grounded; the second terminal of the first transistor M1 is electrically connected to the second terminal of the third transistor M3 through the first inductor L1.

[0066] Figure 4 The second DC / DC converter 121 shown is a bidirectional, non-isolated four-switch Buck-Boost converter, also known as a synchronous rectified Buck-Boost converter. By controlling the switching states of the four transistors, two different circuits are constructed to achieve bidirectional energy flow and buck-boost functionality.

[0067] The first capacitor C1 is connected in parallel with the DC power supply of the DC energy storage device, serving as an input filter capacitor to stabilize the voltage on the DC energy storage device side and absorb high-frequency switching ripple. The positive terminal of the second capacitor C2 is electrically connected to the first connection point, and the negative terminal of the second capacitor C2 is grounded. It serves as an output filter capacitor to stabilize the DC bus voltage and provide smooth DC power to the load.

[0068] The first switching arm includes a first transistor M1 and a second transistor M2 connected in series, between the positive terminal DC+ of the DC energy storage device and ground (GND). The second switching arm includes a third transistor M3 and a fourth transistor M4 connected in series, between the first connection point 130 and ground (GND).

[0069] The first inductor L1 is the energy storage element of the second DC / DC converter 121, connected between the midpoints of the two switching bridge arms. Since the inductor current cannot change abruptly, voltage conversion is achieved by controlling its energy storage and release.

[0070] The second DC / DC converter 121 controls the switching of its operating modes by turning four transistors on and off using pulse width modulation (PWM) signals. In discharge mode, the second DC / DC converter 121 can be considered a synchronous boost converter. The first transistor M1 and the second transistor M2 are controlled by a pair of complementary PWM signals, as are the third transistor M3 and the fourth transistor M4. The drive signals of the two half-bridges have a phase difference. In the energy storage stage, the first transistor M1 is on, the second transistor M2 is off, the third transistor M3 is off, and the fourth transistor M4 is on. The current path is: positive terminal DC+ of the DC energy storage device → first transistor M1 → first inductor L1 → fourth transistor M4 → ground → negative terminal DC- of the DC energy storage device. At this time, the first inductor L1 is directly connected to the two ends of the battery, the current increases linearly, the inductor stores energy, and the DC bus is powered by the second capacitor C2. During the energy release phase, the first transistor M1 is off, the second transistor M2 is on, the third transistor M3 is on, and the fourth transistor M4 is off. Since the inductor current cannot change abruptly, the first inductor L1 generates an induced electromotive force to maintain the current. The current path becomes: right end of the first inductor L1 → third transistor M3 → load → ground → second transistor M2 → left end of the first inductor L1. At this time, the inductor acts as an independent voltage source, pumping its energy into the high-voltage bus through the channel formed by the third transistor M3 and the second transistor M2, thereby realizing the voltage boost function.

[0071] In charging mode, the second DC / DC converter 121 can be considered as a synchronous buck converter. The first transistor M1 remains on, the second transistor M2 remains off, and the third transistor M3 and the fourth transistor M4 are controlled by a pair of complementary PWM signals. During the energy storage phase, when the third transistor M3 is on and the fourth transistor M4 is off, the current path is: first connection point → third transistor M3 → first inductor L1 → first transistor M1 → positive terminal DC+ of the DC energy storage device. At this time, the first inductor L1 is connected across the difference between the DC bus voltage and the battery voltage, and the current increases linearly, storing energy in the inductor. During the energy release phase, when the third transistor M3 is off and the fourth transistor M4 is on, the inductor current is maintained through the freewheeling path. The current path becomes: left end of first inductor L1 → first transistor M1 → positive terminal DC+ of the DC energy storage device → negative terminal DC- of the DC energy storage device → fourth transistor M4 → right end of first inductor L1. At this time, the inductor releases energy, charging the battery.

[0072] By switching logic, both charging and discharging modes are seamlessly implemented on the same hardware topology. Regardless of whether it is charging or discharging mode, the output voltage or charging voltage is controlled in a closed loop by adjusting the duty cycle to achieve voltage regulation.

[0073] Based on the above embodiments, the rectifier is optimized in this embodiment. The rectifier is a three-phase PWM rectifier, and each phase rectifier includes two parallel interleaved single-phase PFC units. The phase difference of the PWM signals of any two phase rectifiers is a first angle, and the phase difference of the PWM signals of the two PFC units in each phase rectifier is a second angle.

[0074] In an ideal three-phase balanced system, the phase difference between the phase voltages is 120 degrees. To ensure the rectifier draws power evenly from a three-phase power supply and that the three-phase input currents are symmetrical and sinusoidal, the preferred first angle is 120 degrees. In other words, the phase difference between the PWM signals of any two rectifier phases is 120 degrees; that is, the phase difference between the PWM signals of phase A and phase B is 120 degrees, the phase difference between the PWM signals of phase B and phase C is 120 degrees, and the phase difference between the PWM signals of phase C and phase A is 120 degrees.

[0075] Furthermore, in certain scenarios, to compensate for imbalances in the grid voltage or to achieve specific control objectives, the phase of each phase rectifier is adjusted slightly and adaptively. In this case, the phase difference between the PWM signals of each phase rectifier is no longer strictly 120 degrees, but fluctuates within a very small range around 120 degrees.

[0076] When the current ripples of two PFC units within the same phase are out of phase, they cancel each other out when combined, significantly reducing the overall input current ripple amplitude while doubling the ripple frequency. Therefore, preferably, the second angle is 180 degrees. In other words, the phase difference between the PWM signals of the two PFC units in each phase rectifier is 180 degrees.

[0077] This disclosure provides a specific circuit structure for an HVDC module, such as... Figure 5 As shown, the circuit topology mainly describes the rectifier 111.

[0078] In one exemplary implementation, such as Figure 5 As shown, the three-phase PWM rectifier includes the second inductor L2, the third inductor L3, the fourth inductor L4, the fifth inductor L5, the sixth inductor L6, the seventh inductor L7, the fifth transistor M5, the sixth transistor M6, the seventh transistor M7, the eighth transistor M8, the ninth transistor M9, the tenth transistor M10, the eleventh transistor M11, the twelfth transistor M12, the thirteenth transistor M13, the fourteenth transistor M14, the fifteenth transistor M15, the sixteenth transistor M16, the third capacitor C3, and the fourth capacitor C4.

[0079] Specifically, the first terminals of the second inductor L2 and the third inductor L3 are electrically connected to phase A of the AC power supply; the first terminals of the fourth inductor L4 and the fifth inductor L5 are electrically connected to phase B of the AC power supply; and the first terminals of the sixth inductor L6 and the seventh inductor L7 are electrically connected to phase C of the AC power supply. The third capacitor C3 and the fourth capacitor C4 are connected in series to form a capacitor branch. The first terminals of the fifth transistor M5, sixth transistor M6, seventh transistor M7, eighth transistor M8, ninth transistor M9, and tenth transistor M10 are all electrically connected to the positive terminal of the first DC / DC converter and the first terminal of the capacitor branch. The second terminals of the eleventh transistor M11, twelfth transistor M12, thirteenth transistor M13, fourteenth transistor M14, fifteenth transistor M15, and sixteenth transistor M16 are all electrically connected to the positive terminal of the first DC / DC converter and the first terminal of the capacitor branch. The negative terminal of the DC converter and the second terminal of the capacitor branch are electrically connected; the second terminal of the second inductor L2 is electrically connected to the second terminal of the fifth transistor M5 and the first terminal of the eleventh transistor M11, respectively; the second terminal of the third inductor L3 is electrically connected to the second terminal of the sixth transistor M6 and the first terminal of the twelfth transistor M12, respectively; the second terminal of the fourth inductor L4 is electrically connected to the second terminal of the seventh transistor M7 and the first terminal of the thirteenth transistor M13, respectively; the second terminal of the fifth inductor L5 is electrically connected to the second terminal of the eighth transistor M8 and the first terminal of the fourteenth transistor M14, respectively; the second terminal of the sixth inductor L6 is electrically connected to the second terminal of the ninth transistor M9 and the first terminal of the fifteenth transistor M15, respectively; and the second terminal of the seventh inductor L7 is electrically connected to the second terminal of the tenth transistor M10 and the first terminal of the sixteenth transistor M16, respectively.

[0080] The aforementioned rectifier 111 is a two-way interleaved parallel three-phase six-switch rectifier. By operating two three-phase full-bridge rectifier units in parallel and using interleaved control technology, the system performance is improved. Furthermore, by employing TCM frequency conversion control, semiconductor soft-switching is ensured to achieve high frequency and high efficiency.

[0081] Among them, the second inductor L2, the fifth transistor M5 and the eleventh transistor M11 form the first PFC unit of phase A, and the third inductor L3, the sixth transistor M6 and the twelfth transistor M12 form the second PFC unit of phase A. The first PFC unit and the second PFC unit of phase A are controlled by a PWM signal with a phase difference of 180 degrees, forming the phase A rectifier of the three-phase PWM rectifier.

[0082] Similarly, the fourth inductor L4, the seventh transistor M7, and the thirteenth transistor M13 form the first PFC unit of phase B, and the fifth inductor L5, the eighth transistor M8, and the fourteenth transistor M14 form the second PFC unit of phase B. The first and second PFC units of phase B are controlled by a PWM signal with a phase difference of 180 degrees, forming the phase B rectifier of the three-phase PWM rectifier. The sixth inductor L6, the ninth transistor M9, and the fifteenth transistor M15 form the first PFC unit of phase C, and the seventh inductor L7, the tenth transistor M10, and the sixteenth transistor M16 form the second PFC unit of phase C. The first and second PFC units of phase C are controlled by a PWM signal with a phase difference of 180 degrees, forming the phase C rectifier of the three-phase PWM rectifier.

[0083] The A-phase rectifier, B-phase rectifier, and C-phase rectifier are controlled by a PWM signal with a phase difference of 120 degrees, forming a three-phase PWM rectifier.

[0084] The third capacitor C3 and the fourth capacitor C4 are connected in series to form the main DC bus support and filter capacitor for the entire rectifier. The output terminals of both rectifier units are connected in parallel to this main DC bus.

[0085] Taking the first PFC unit of phase A as an example, let's introduce the working principle of PFC. During one switching cycle, when the fifth transistor M5 is off and the eleventh transistor M11 is on, current flows from the grid through the second inductor L2 and the eleventh transistor M11, storing electrical energy in the inductor in the form of a magnetic field. When the fifth transistor M5 is on and the eleventh transistor M11 is off, the inductor current cannot change abruptly, generating an induced voltage that is superimposed on the grid voltage. This higher voltage charges the output capacitor and supplies power to the load. The controller controls the magnitude of the inductor current by continuously adjusting the switching timing (i.e., the PWM duty cycle) of the fifth transistor M5 and the eleventh transistor M11, ensuring that its instantaneous value always closely follows the sinusoidal waveform of the phase A input voltage.

[0086] The working principle of this three-phase PWM rectifier is spatial interleaving, meaning that two parallel three-phase rectifiers use the same PWM modulation strategy, but the PWM signals are 180 degrees out of phase. The basic principle of a single-channel three-phase PWM rectifier is that each channel is itself a standard three-phase voltage-source PWM rectifier. Through SVPWM (Space Vector Pulse Width Modulation) control technology, controlling the duty cycle of the six switching transistors allows the input current to be sinusoidal and in phase with the voltage, and it can boost unstable AC input to a stable DC voltage (e.g., 800V).

[0087] Based on the above embodiments, this disclosure provides a specific circuit structure for an HVDC module, such as... Figure 6As shown, this circuit topology mainly describes the first DC / DC converter. For example... Figure 6 As shown, the first DC / DC converter 112 includes a switching network 1121, a resonant network 1122, and a rectifier-filter network 1123 connected in sequence.

[0088] In this embodiment, the first DC / DC converter 112 adopts a star-connected three-phase interleaved LLC soft-switching circuit, and the switching components are preferably silicon carbide.

[0089] Specifically, the three-phase LLC circuit is a high-frequency soft-switching topology that achieves high-efficiency power conversion (>98%) through a resonant mechanism. It is mainly used in medium-to-high power applications (3-30kW), such as server power supplies and electric vehicle chargers. Its core structure consists of three parts: a switching network 1121, a resonant network 1122, and a rectifier-filter network 1123.

[0090] The switching network 1121 includes a three-phase full-bridge circuit composed of six MOSFETs / IGBTs. It adopts 120° phase shift control to generate three high-frequency square waves with a phase difference of 120°. It uses resonance to achieve zero-voltage turn-on (ZVS) and significantly reduces switching losses.

[0091] The resonant network 1122 includes: a resonant inductor ( ), resonant capacitor ( ), transformer magnetizing inductance ( This forms an LC series resonance and a transformer magnetizing inductance. The parallel structure (hence the name LLC) works on the principle that at the resonant frequency point ( =1 / (2π√( Sinusoidal current, It provides voltage regulation freedom, enabling a wide input / output range.

[0092] The rectifier filter network 1123 adopts a three-phase bridge rectifier circuit, including: 12 diodes (or synchronous rectifier MOS) and an LC filter to smooth the DC output; the rectifier side achieves zero current turn-off (ZCS) to reduce diode reverse recovery losses.

[0093] In one possible implementation, such as Figure 7As shown, the switching network 1121 includes a seventeenth transistor M17, an eighteenth transistor M18, a nineteenth transistor M19, a twentieth transistor M20, a twenty-first transistor M21, and a twenty-first transistor M22. The first terminals of the seventeenth transistor M17, eighteenth transistor M18, and nineteenth transistor M19 are electrically connected to the positive output terminal of the rectifier. The second terminals of the twentieth transistor M20, twenty-first transistor M21, and twenty-first transistor M22 are also electrically connected to the positive output terminal of the rectifier. The second terminal of the seventeenth transistor M17 is electrically connected to the first terminal of the twentieth transistor M20; the second terminal of the eighteenth transistor M18 is electrically connected to the first terminal of the twenty-first transistor M21; and the second terminal of the nineteenth transistor M19 is electrically connected to the first terminal of the twenty-second transistor M22.

[0094] Furthermore, such as Figure 7 As shown, the resonant network 1122 includes an eighth inductor L8, a ninth inductor L9, a tenth inductor L10, a fifth capacitor C5, a sixth capacitor C6, a seventh capacitor C7, a first transformer T1, a second transformer T2, and a third transformer T3. The eighth inductor L8 and the fifth capacitor C5 form a first series branch; the ninth inductor L9 and the sixth capacitor C6 form a second series branch; and the tenth inductor L10 and the seventh capacitor C7 form a third series branch. The first end of the first series branch is connected to the second end of the seventeenth transistor M17, and the second end of the first series branch is connected to the first end of the primary coil of the first transformer T1. The first end of the second series branch is connected to the second end of the eighteenth transistor M18, and the second end of the second series branch is connected to the first end of the primary coil of the second transformer T2. The first end of the third series branch is connected to the second end of the nineteenth transistor M19, and the second end of the third series branch is connected to the first end of the primary coil of the second transformer T3. The second ends of the primary coils of the first transformer T1, the second transformer T2, and the third transformer T3 are connected. The second terminal of the secondary coil of the first transformer T1, the second terminal of the secondary coil of the second transformer T2, and the second terminal of the secondary coil of the third transformer T3 are connected.

[0095] Furthermore, such as Figure 7As shown, the rectifier-filter network 1123 includes a second diode D2, a third diode D3, a fourth diode D4, a fifth diode D5, a sixth diode D6, a seventh diode D7, and an eighth capacitor C8. The positive terminals of the second diode D2, the third diode D3, and the fourth diode D4 are connected to the positive terminal of the eighth capacitor C8, and the negative terminals of the fifth diode D5, the sixth diode D6, and the seventh diode D7 are connected to the negative terminal of the eighth capacitor C8. The negative terminals of the second diode D2 and the fifth diode D5 are respectively connected to the first terminal of the secondary coil of the first transformer T1, the negative terminals of the third diode D3 and the sixth diode D6 are respectively connected to the first terminal of the secondary coil of the second transformer T2, and the negative terminals of the fourth diode D4 and the seventh diode D7 are respectively connected to the first terminal of the secondary coil of the third transformer T3. The eighth capacitor C8 is connected in parallel with the load 30.

[0096] In some embodiments, the first branch further includes: a first diode D1, the positive terminal of which is electrically connected to the output terminal of the first DC / DC converter, and the negative terminal of which is connected to the load through a DC bus.

[0097] like Figure 8 As shown, the positive terminal of the eighth capacitor in the rectifier-filter network 1123 is the output terminal of the first DC / DC converter. That is, the positive terminal of the first diode D1 is connected to the positive terminal of the eighth capacitor C8 in the rectifier-filter network 1123, and the negative terminal of the first diode D2 is connected to the positive terminal of the load 30. In addition, the positive terminal of the first diode D1 is grounded through the ninth capacitor C9.

[0098] Because diodes have unidirectional conductivity, they only allow current to flow from the positive terminal to the negative terminal, and turn off the diodes in the opposite direction. This prevents large currents from flowing back from the DC bus to the first DC / DC converter 112, thus avoiding secondary damage to the converter.

[0099] In some embodiments, such as Figure 9 As shown, the high-voltage DC power supply also includes a controller 130, which is connected to the rectifier 111, the first DC / DC converter 112 and the second DC / DC converter 121 respectively, and is used to control the high-voltage DC power supply to switch between multiple operating modes.

[0100] The controller 130 controls the switching of the high-voltage DC power supply between various operating modes by monitoring a set of operating status parameters. These operating status parameters include: AC power supply status, DC bus voltage, load current, and DC energy storage device status. AC power supply status includes whether the AC power input voltage is within the normal range; DC bus voltage includes whether its value is stable at the target value (e.g., 800V); and the real-time load power demand. DC energy storage device status includes, but is not limited to: battery pack voltage, current, state of charge, and temperature.

[0101] In one implementation, the controller monitors the input voltage and frequency of the AC power supply. When the input voltage and frequency are within a preset normal range (e.g., voltage at 380V ± 15%, frequency at 50Hz ± 2%), and the real-time calculated load power is lower than the AC power supply threshold, the controller switches to AC power supply mode. In AC power supply mode, the controller employs dual closed-loop control for the first branch: the outer voltage loop uses the DC bus voltage as feedback to stabilize the DC bus voltage at 800V; the inner current loop controls the power devices to achieve rapid dynamic response. Simultaneously, the controller sends control commands to the bidirectional DC / DC converter in the second branch, causing it to operate in buck mode and employing a constant current-constant voltage charging algorithm to charge the battery based on its real-time state of charge and temperature.

[0102] When the power grid supply conditions are good and the load demand is within the AC side capacity range, priority should be given to using grid power to improve grid utilization. Simultaneously, energy should be supplemented to DC energy storage devices to ensure they are in good standby condition to cope with potential grid anomalies.

[0103] When the controller detects that the AC power supply is normal, but the real-time load power exceeds the aforementioned AC power supply threshold, it controls the high-voltage DC power supply to enter a combined power supply mode. At this time, the controller applies power limiting control or current limiting control to the first branch to ensure its output power does not exceed the AC power supply threshold. For the second branch, the controller controls its bidirectional DC / DC converter to operate in boost mode. The control loop of this bidirectional DC / DC converter automatically compensates for the load power deficiency. Its outer voltage loop detects a slight drop in bus voltage due to insufficient power and generates an additional current command to drive the battery to discharge. The discharge power is exactly equal to the difference between the total load power and the maximum output power of the AC branch. This voltage feedback-based power distribution mechanism ensures the stability of the bus voltage under peak load impacts.

[0104] The combined power supply mode is designed for the instantaneous peak power consumption commonly seen in modern data centers and other scenarios. Without upgrading the front-end AC power distribution capacity, it utilizes the characteristics of short-term high-power discharge of the energy storage system to jointly cope with the peak demand of the load, achieving peak shaving and valley filling. This satisfies the load performance while optimizing the cost of the high-voltage DC power supply.

[0105] Specifically, the output power from the grid is limited to below an AC power supply threshold. The controller calculates the output power P_ac from the first branch (AC path) in real time and sets a desired AC power supply threshold P_set. When the controller predicts or detects that the output power P_ac of the first branch is about to exceed the AC power supply threshold P_set, it activates the combined power supply mode. The controller sends a control command to the bidirectional DC / DC converter of the second branch, causing it to discharge at the battery output power P_battery. Here, the battery output power is equal to the difference between the total load power P_load and the AC power supply threshold P_set. The battery provides the differential power, ensuring that the total power drawn from the grid is always controlled below the AC power supply threshold P_set, thus eliminating power spikes and avoiding high monthly demand charges due to occasional peaks.

[0106] Furthermore, the system charges the battery during low-price periods and discharges it during high-price periods, replacing the grid to supply power to the load. The controller has a built-in clock and electricity price model (such as setting peak, flat, and valley periods). During the nighttime valley period (low-price period), it operates in normal power supply mode and charges the battery as much as possible to store low-priced energy. During the daytime peak period (high-price period), even if the grid is normal, the controller actively activates the joint power supply mode, controlling the first branch to operate at a lower power (or maintaining the AC power supply threshold P_set), while simultaneously controlling the battery to discharge, jointly supplying power to the load. This reduces or even completely avoids drawing power from the expensive grid during peak hours, achieving low-storage, high-generation, and low-cost valley electricity to replace high-cost peak electricity, thus reducing electricity costs.

[0107] In one implementation, the controller is equipped with a high-speed AC fault detection circuit. If the controller detects AC voltage loss, undervoltage, overvoltage, or frequency exceeding limits, it will control the high-voltage DC power supply to operate in battery-powered mode. Specifically, it controls all switches in the first branch to turn off, disconnecting them from the AC bus to prevent damage under abnormal power conditions. A control command is sent to the bidirectional DC / DC converter in the second branch, causing it to instantly switch to discharge mode.

[0108] Furthermore, to ensure a smooth DC bus voltage transition during the switching process, the controller employs pre-synchronization control technology: before the second branch is officially connected, its output voltage is controlled to precisely track the current DC bus voltage. Only after voltage matching is achieved is the control loop closed, thus achieving a "connect first, disconnect later" current flow. In this mode, the bidirectional DC / DC converter, through voltage-current dual closed-loop control, can ignore the continuous drop in battery voltage, providing a stable voltage to the DC bus.

[0109] When grid power is unavailable, backup power is activated to ensure the continuous operation of the load and prevent business interruption due to power failure.

[0110] Furthermore, such as Figure 9 As shown, the AC power supply can be converted to a different voltage level by a transformer before being connected to a high-voltage DC power supply. Furthermore, a switch can be connected in series between the converter and the high-voltage DC power supply to quickly disconnect the power supply path between the grid and the high-voltage DC power supply in the event of a grid fault.

[0111] The performance parameters of the high-voltage DC power supply provided in this embodiment are shown in Table 1.

[0112] Table 1

[0113] The high-voltage DC power supply provided in this disclosure has the following advantages: 1. Compared to 240V HVDC systems, 800V HVDC systems can handle AI loads of 500KW or more in cabinets.

[0114] 2. Compared to 240V HVDC systems, 800V HVDC systems can solve the problem of AI load fluctuations, reduce the power distribution capacity of upstream and downstream stages, and reduce investment.

[0115] 3. Compared to a 240V HVDC system, an 800V HVDC system can connect to lithium battery packs up to 1000V and adopts a combined power supply mode, which can improve IT output (more servers can be installed with the same power capacity), thereby reducing monthly rental costs.

[0116] 4. Compared to a 240V HVDC system, an 800V HVDC system can improve efficiency by 1% to 2% and reduce operating costs.

[0117] 5. Compared to the 240V HVDC system, the 800V HVDC system provides a more stable voltage output, reducing voltage fluctuations on the output bus during battery charging and discharging. This significantly improves the efficiency of the downstream server power supply and reduces power distribution link costs, thus helping to optimize investment and operating costs.

[0118] 6. Compared to the 240V HVDC system, the 800V HVDC system achieves safer operation of the energy storage battery by increasing the lithium battery voltage to over 850V.

[0119] Based on the same inventive concept, this disclosure also provides a power system, which includes any of the above-described high-voltage DC power supplies.

[0120] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the following claims.

[0121] It should be understood that this disclosure is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this disclosure is limited only by the appended claims.

Claims

1. A high-voltage DC power supply, characterized in that, include: N parallel high-voltage direct current (HVDC) power supply modules, whose input terminals are electrically connected to an AC power source and whose output terminals are electrically connected to a load via a DC bus, are used to provide DC power to the load. N is an integer greater than or equal to 1. Each of the HVDC modules includes: The first branch includes a rectifier connected in series and a first DC / DC / DC converter, used to convert and stabilize the AC power output from the AC power source into the first DC power. The second branch includes a DC energy storage device connected in series and a second DC / DC converter, used to convert and stabilize the DC power output by the DC energy storage device into a second DC power in discharge mode. The first connection point is used to connect the output terminal of the first branch and the output terminal of the second branch in parallel, so that the first DC power and the second DC power are superimposed at the first connection point and together serve as the output DC power of the HVDC module.

2. The high-voltage DC power supply according to claim 1, characterized in that, The second DC / DC converter is a bidirectional DC / DC converter.

3. The high-voltage DC power supply according to claim 2, characterized in that, The second DC / DC converter is used to convert a portion of the first DC power supply into a voltage adapted to the DC energy storage device in charging mode, so as to charge the DC energy storage device.

4. The high-voltage DC power supply according to claim 3, characterized in that, The second DC / DC converter includes: a first transistor, a second transistor, a third transistor, a fourth transistor, a first capacitor, a second capacitor, and a first inductor; The first capacitor is connected in parallel with the DC energy storage device, the positive terminal of the second capacitor is electrically connected to the first connection point, and the negative terminal of the second capacitor is grounded; The first terminal of the first transistor is electrically connected to the positive terminal of the DC energy storage device, the second terminal of the first transistor is electrically connected to the first terminal of the second transistor, and the second terminal of the second transistor is grounded. The first terminal of the third transistor is electrically connected to the first connection point, the second terminal of the third transistor is electrically connected to the first terminal of the fourth transistor, and the second terminal of the fourth transistor is grounded. The second terminal of the first transistor is electrically connected to the second terminal of the third transistor through the first inductor.

5. The high-voltage DC power supply according to claim 1, characterized in that, The DC energy storage device includes L sets of battery packs connected in parallel, where L is an integer greater than or equal to 1.

6. The high-voltage DC power supply according to claim 5, characterized in that, The battery pack includes a lithium battery pack.

7. The high-voltage DC power supply according to claim 1, characterized in that, Each HVDC module includes M parallel first branches, where M is an integer greater than or equal to 1.

8. The high-voltage DC power supply according to claim 7, characterized in that, The first branch also includes: The first diode has its positive terminal electrically connected to the output terminal of the first DC / DC converter, and its negative terminal electrically connected to the first connection point.

9. The high-voltage DC power supply according to claim 7, characterized in that, The rectifier is a three-phase pulse width modulation (PWM) rectifier, and each phase rectifier includes two parallel interleaved single-phase power factor correction (PFC) units. The phase difference between the PWM signals of any two phase rectifiers is the first angle, and the phase difference between the PWM signals of the two PFC units in each phase rectifier is the second angle.

10. The high-voltage DC power supply according to claim 7, characterized in that, The first DC / DC converter includes a switching network, a resonant network, and a rectifier-filter network connected in sequence.

11. The high-voltage DC power supply according to claim 3, characterized in that, Also includes: The controller is electrically connected to the rectifier, the first DC / DC converter, and the second DC / DC converter, respectively, and is used to control the high-voltage DC power supply to switch between multiple operating modes.

12. An electric power system, characterized in that, The power system includes a high-voltage DC power supply as described in any one of claims 1 to 11.

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