Modular voltage stabilizing device, control method thereof and new energy power direct current power supply system

Abstract

This invention relates to a modular voltage regulator and its control method, as well as a DC power supply system for new energy power. The voltage regulator circuit of the voltage regulator adopts a modular design, and the voltage regulator modules are switched on and off in priority according to the predicted or measured load of the control bus. The voltage regulator controller controls the output of the voltage regulator circuit through the feedback control parameters of the DC / DC converter unit. When the charging circuit is in floating charging or equalizing charging state, the corresponding set feedback control parameters are used. When the charging circuit is in a locked state, the feedback control parameters are determined by the predicted results of the DC bus load or the DC bus load and load change rate, as well as the real-time energy storage of the energy storage circuit. This invention achieves dynamic optimization of the control model and control function, which is beneficial to improving output characteristics, extending product life, and is suitable for applications with limited space and relatively harsh environmental conditions, such as offshore wind power. It can mainly be used as an uninterruptible DC power supply for new energy power systems.

Description

Technical Field

[0001] This invention relates to a DC-DC modular voltage regulator and its control method, and also to a new energy power DC power supply system using such a voltage regulator. It can be mainly used as a DC uninterruptible power supply for secondary equipment and other auxiliary equipment in high-voltage / ultra-high-voltage substations and power plant step-up substations. It belongs to the field of power technology, especially the field of new energy intelligent power generation and transmission technology. Background Technology

[0002] In existing power systems, including those powered by new energy sources such as wind and solar power, secondary equipment and other related auxiliary equipment in power stations require DC uninterruptible power supply (UPS) systems. These systems convert AC power from transmission lines into stable DC constant voltage output through AC-DC and DC-DC converters and batteries. For example, Chinese invention document CN113937750A discloses a wind-solar-storage complementary distributed energy generation system and its control method. The system includes: a wind power generation device for generating AC power using wind energy; a solar power generation device for generating DC power using solar energy; and an energy storage device for storing electrical energy to absorb excess electricity when the DC bus voltage is higher than the rated voltage, and for releasing electrical energy to maintain the stability of the DC bus voltage when the DC bus voltage is lower than the rated voltage. However, due to the difference between the charging and discharging voltages of the batteries, the DC bus voltage will change accordingly under different battery operating conditions, thus limiting the improvement of voltage regulation performance. Taking offshore wind power as an example, most batteries currently used are nickel-cadmium batteries, each with a rated voltage of 1.2V. A typical 110V DC system requires about 90 batteries connected in series. The float charge voltage of the entire battery bank is 1.44V × 90 = 129.6V (129V can be used in practice), and the equalization charge voltage is 1.55V × 90 = 139.5V (139V can be used in practice). Both the equalization and float charge voltages are significantly higher than 110V. Therefore, regardless of whether the batteries are in equalization or float charge mode, the excessively high bus voltage may damage some secondary equipment (e.g., control loads). A feasible solution is to install a step-down silicon chain between the batteries and the DC bus. The step-down silicon chain is controlled by a control device to reduce the voltage connected to the DC bus to the allowable range of around 110V. For example, Chinese invention document CN113572259A discloses an integrated DC power supply conversion and feeding device, including a DC insulation detection module, a step-down module, an alarm module, an indicator module, a current and voltage monitoring module, and a feeding module. The step-down module uses a step-down silicon chain. For different DC voltage levels, only the silicon chain voltage automatic voltage regulator needs to be replaced to ensure the normal voltage of the DC bus. Chinese invention document CN103683405A discloses a DC power supply panel based on a dual silicon chain step-down device, including a DC voltage regulator, a charging device, a battery pack, and two silicon chain step-down devices. The two silicon chain step-down devices are connected in parallel between the battery pack and the control bus. Each silicon chain step-down device consists of 6 to 8 high-power diodes connected in series. The anode of the silicon chain step-down device is connected to the output of the battery pack, and the cathode of the silicon chain unit is connected to the control bus.

[0003] These existing technologies each have their own characteristics and are suitable for their respective applications, but they still have certain limitations. For example, buck converters can only step down voltage, not step up. When the charging circuit is locked (stops working) due to a three-phase power failure, the battery pack gradually discharges, and the voltage may fall below the DC bus's required lower limit, making it impossible to guarantee the safe and stable operation of the equipment. In particular, even if a voltage regulator circuit with buck-boost functionality is used, the current voltage regulation control strategies and methods still have room for improvement. For example, the currently mature buck-boost regulator circuits suitable for industrial applications are based on (or have) a DC / DC converter unit. Their feedback control circuit is usually a dual-loop control circuit. During the design phase, a set of fixed control parameters is set based on the rated input voltage and typical load. During operation, the control parameters are not modified online according to changes in load or input voltage. Since the battery pack's energy storage is limited and gradually decreases during discharge, when there are large changes in the load or energy storage circuit's energy storage, slow response, poor dynamics, overshoot, voltage oscillation, and other phenomena are prone to occur, making it difficult to guarantee output stability. Summary of the Invention

[0004] The purpose of this invention is to provide a modular voltage regulator and its control method, as well as a new energy power DC power supply system, to improve the output characteristics of uninterruptible DC power supply in the power system and better meet actual needs.

[0005] The technical solution of this invention is: This modular voltage regulator includes a voltage regulator circuit and a voltage regulator controller. The voltage regulator circuit adopts a modular design, consisting of several voltage regulator modules connected in parallel. Each voltage regulator module includes a DC / DC conversion unit (DC / DC conversion circuit) and an output-side smoothing filter unit (or second smoothing filter unit) connected to the output side of the DC / DC conversion unit. The input terminal of the voltage regulator module (the input side of the DC / DC conversion unit) is used to connect to the connection terminal of the energy storage circuit (e.g., battery pack) and the output terminal of the charging circuit. The output terminal (the output side of the output-side smoothing filter unit) is used to connect to the control DC bus (the DC bus used to supply power to the control load, referred to as the control bus). The DC / DC conversion unit has a feedback control circuit. The voltage regulator controller controls the feedback control parameters of the DC / DC conversion unit (the control parameters of the feedback control circuit) to ensure that the output of the voltage regulator circuit is a set constant voltage output. The voltage regulator controller acquires / obtains the operating status of the charging circuit on the input side of the voltage regulator circuit and sets (or determines) the feedback control parameters of the DC / DC conversion unit in the following manner: 1) If the charging circuit is in float charging mode, use the corresponding (predetermined) feedback control parameters. 2) If the charging circuit is in the equalization charging state, the corresponding feedback control parameters for that state shall be used; 3) If the charging circuit is in a locked state (stopped working state), the DC bus load is predicted based on the prediction model, and the feedback control parameters for the corresponding time are set according to the predicted DC bus load and the real-time energy storage of the energy storage circuit; or, the rate of change of the DC bus load and the linear bus load is predicted based on the prediction model, and the feedback control parameters for the corresponding time are set according to the predicted DC bus load and the linear bus load rate of change and the real-time energy storage of the energy storage circuit.

[0006] Depending on the structure or characteristics of the DC / DC converter unit, any suitable control circuit can be used, such as a dual-loop control circuit. The feedback control parameters can be set according to the specific structure and characteristics of the feedback control circuit.

[0007] For both float charging and equalizing charging states, the float charging voltage or equalizing charging voltage can be considered as the input voltage of the voltage regulator circuit, and the set constant voltage output (constant output voltage) can be considered as the target output voltage of the voltage regulator circuit. The required voltage change rate of the voltage regulator circuit can be calculated based on the float charging voltage and the set constant voltage output. Any suitable existing technology can be used to adjust (set) the feedback control parameters (feedback control parameter set) for the corresponding state. Since the power output of each voltage regulator module can be kept within a suitable range by switching the voltage regulator modules on and off when the relevant load changes significantly, the power output of the voltage regulator modules can be kept within a suitable range during the feedback control parameter adjustment process. The load can be set according to the suitable power output range of the voltage regulator device.

[0008] Preferably, the feedback control circuit of the DC / DC converter unit adopts a dual-loop control circuit (a feedback control circuit with an outer voltage loop and an inner current loop). The feedback control parameters of the feedback control circuit include the proportional gain of the current loop (Kp_i), the integral gain of the current loop (Ki_i), the proportional gain of the voltage loop (Kp_v), and the integral gain of the voltage loop (Ki_v). Other control parameters may also be provided or used when appropriate.

[0009] Preferably, the DC / DC converter unit adopts a resonant DC / DC converter unit adapted to PFM signal control. The dual-loop control circuit is equipped with a PFM control module (PFM modulator). The PFM control module sends out drive signals to the DC / DC switching transistor (the switching transistor in the resonant DC / DC converter circuit or other switching elements) according to the control command signal of the dual-loop circuit (e.g., the conduction time Ton command sent by the current loop). The DC / DC switching transistor is controlled through the PFM drive signal, thereby obtaining the required constant voltage output.

[0010] The DC / DC converter unit can also use any other suitable DC / DC converter circuit (including components), such as a hard-switching PWM converter adapted to PWM signal control.

[0011] Preferably, both the input and output sides of the voltage regulator module are equipped with switching switches (which can be suitable electronic switches, soft switches, or suitable hard switches, such as circuit breakers, or a combination of both). The switching switches on the input and output sides of the same voltage regulator module are linked, that is, the switching actions are implemented synchronously and the same switching state is maintained. The voltage regulator controller controls the state of the switching switches of each voltage regulator module according to the predicted or measured value of the control load (the load on the control bus), thereby realizing the switching of the voltage regulator modules and ensuring that each voltage regulator module in operation operates within a suitable power output range.

[0012] The priority order for power-on of voltage regulator modules can be determined based on their expected remaining lifespan (e.g., the difference between rated lifespan and actual usage time, or by performance testing / evaluation), temperature rise, and / or output stability. For example, voltage regulator modules with longer remaining rated lifespans are prioritized over those with shorter remaining rated lifespans; modules with lower temperature rise during long-term operation are prioritized over those with higher temperature rise (based on recent historical data); and modules with high output stability are prioritized over those with low output stability (based on recent historical data). Alternatively, a weighted average can be applied to any two or three of the above priority methods (priority order), and the priority order can be determined based on the weighted average result. By setting a priority order for power-on and switching voltage regulator modules accordingly, output characteristics can be improved and lifespan extended.

[0013] The voltage regulator controller can be a local microprocessor located in the voltage regulator device, or some functions of the voltage regulator processor (e.g., predictive model training or updating) can be executed by a host computer (e.g., the monitoring unit of the DC power supply). In this case, the local microprocessor located in the voltage regulator device and the corresponding host computer (corresponding functions) can be regarded together as the voltage regulator controller. Any suitable existing technology can be used to realize the communication and collaboration between the local microprocessor and the corresponding host computer.

[0014] The modular voltage regulator of the present invention can be controlled using any of the control methods for modular voltage regulators disclosed in the present invention.

[0015] A control method for a modular voltage regulator, wherein the modular voltage regulator employs a voltage regulator circuit based on a DC / DC converter and includes a voltage regulator controller. The input terminal of the DC / DC converter is connected between the connection terminal of an energy storage circuit (e.g., a battery pack) and the output terminal of a charging circuit. The DC / DC converter includes a feedback control circuit (e.g., a dual-loop control circuit). The voltage regulator controller controls the feedback control parameters of the DC / DC converter (control parameters of the feedback control circuit) to ensure that the output of the voltage regulator circuit is a set constant voltage output. The voltage regulator controller acquires / obtains the operating state of the charging circuit on the input side of the voltage regulator circuit and sets the feedback control parameters of the DC / DC converter in the following manner: 1) If the charging circuit is in float charging mode, use the corresponding (predetermined) feedback control parameters. 2) If the charging circuit is in the equalization charging state, the corresponding feedback control parameters for that state shall be used; 3) If the charging circuit is in a locked state (stopped working state), the DC bus load (hereinafter referred to as bus load, or load) is predicted based on the prediction model, and the feedback control parameters for the corresponding time are set to preset feedback control parameters corresponding to the predicted DC bus load and the real-time energy storage of the energy storage circuit; or, the rate of change of the DC bus load and the linear bus load is predicted based on the prediction model, and the feedback control parameters for the corresponding time are set to preset feedback control parameters corresponding to the predicted rate of change of the DC bus load and the linear bus load and the real-time energy storage of the energy storage circuit.

[0016] Preferably, the prediction model used is an LSTM prediction model (univariate output or multivariate output) obtained by training an LSTM (Long Short-Term Memory) neural network.

[0017] Preferably, the DC bus load adopts an equivalent load resistance Req, where Req = Uo / Io (bus voltage Uo divided by bus current Io). Correspondingly, the rate of change of the DC bus load is the DC bus load Req at the corresponding time (time t). t Compared with the DC bus load Req at the previous moment t-1 The ratio (Req) t / Req t-1 ).

[0018] Preferably, the output data (target value) of the prediction model is the load of the DC bus (closing DC bus and control DC bus), or the DC bus load and the DC bus load change rate. The input data of the prediction model is a series of consecutive prediction data records (or multiple sets or multiple records) with the time sequence preceding the data (an array of several data at the same time is called a data record).

[0019] Forecast data records (e.g., in the form of an array with timestamps) can be derived from remote sensing data, that is, some or all of the remote sensing data can be used as forecast data records.

[0020] The feedback control parameters can be determined based on the feedback control circuit used.

[0021] Preferably, when a dual-loop control circuit is used to control the DC / DC converter unit, or in other words, when the feedback control circuit of the DC / DC converter unit is a dual-loop control circuit, the feedback control parameters include the current loop proportional gain (Kp_i), the current loop integral gain (Ki_i), the voltage loop proportional gain (Kp_v), and the voltage loop integral gain (Ki_v).

[0022] Preferably, the DC / DC converter unit adopts a resonant DC / DC converter unit adapted to PFM signal control. The dual-loop control circuit is equipped with a PFM control module. The PFM control module sends out a drive signal to the DC / DC switch transistor according to the control command signal of the dual-loop circuit. The DC / DC switch transistor (the switch transistor of the DC / DC converter unit) is controlled by the PFM drive signal, thereby obtaining the required constant voltage output.

[0023] The control method of the modular voltage regulator of the present invention is applicable to any modular voltage regulator disclosed in the present invention and can be used for the control of any modular voltage regulator disclosed in the present invention.

[0024] New energy power DC power supply system includes: The charging device is equipped with a charging circuit and a charging controller. The charging circuit is used to convert three-phase AC power into DC power under the control of the charging controller. Its input side is connected to three-phase AC power (or primary power supply, or raw power supply), and its output side is connected to the closing DC bus (referred to as closing bus). The energy storage device uses a battery as the energy storage element, and its connection terminal is connected to the output side of the charging circuit. A voltage regulator is used to convert the input DC power into a constant voltage output. The input terminal of the voltage regulator module is connected to the energy storage circuit connection terminal and the charging circuit output terminal, and the output terminal of the voltage regulator module is connected to the control DC bus. The voltage regulator adopts any of the modular voltage regulators disclosed in this invention, and / or the control method of the voltage regulator adopts any of the control methods of the modular voltage regulators disclosed in this invention.

[0025] Preferably, the output side of the charging circuit is connected to the control DC bus via a switching switch.

[0026] During normal operation of the voltage regulator, the switching switch should be kept in the open position. When the voltage regulator fails to work, the switching switch should be closed so that the output of the charging circuit or the input of the energy storage circuit can be connected to the control DC bus to provide emergency power to the control load.

[0027] The operating status of the voltage regulator (voltage regulator circuit) can be monitored through the monitoring system (or monitoring unit) of the voltage regulator controller and / or DC power supply, and the switching switch can be closed when needed.

[0028] The beneficial effects of this invention are as follows: By employing different control strategies to determine the feedback control parameters for the three states of the charging circuit—float charging, equalization charging, and shutdown—it can better adapt to the control requirements of each state. Furthermore, in the float charging and equalization charging states, the feedback control parameters are adjusted according to the stability of the charging circuit output, ensuring that even fluctuations do not hinder the constant output. Therefore, there is no need to use a predictive model to predict the bus load, effectively reducing or avoiding unnecessary data processing. However, when the energy storage circuit (battery pack) is powered (charging circuit shutdown), a predictive model is introduced to predict the bus load and the rate of change of the bus load. Based on the prediction results and the battery storage... The dual-loop control parameters for active energy adjustment over time achieve dynamic optimization of the control model and control function, adapting to the control requirements of energy storage circuits (battery packs) under power supply due to changes in battery energy storage and load, which is beneficial for improving output characteristics. Because the voltage regulator circuit adopts a modular design, it can actively switch on and off the voltage regulator module based on load detection or prediction results, and can select the activated voltage regulator module according to priority, which helps ensure the normal operation of the voltage regulator module and extends product lifespan. Furthermore, the introduction of passive PFC, resonant soft-switching dual-loop control, microprocessor intelligent management, and current sharing control in the charging and voltage regulator circuits facilitates high efficiency, high power factor, high reliability, and intelligent management.

[0029] This invention is suitable for applications with limited space and relatively harsh environmental conditions, such as offshore wind power. It can be used as an uninterruptible DC power source for new energy power systems and power transmission and distribution grid systems, and can also be used in other suitable applications. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the DC power supply system of the present invention; Figure 2 This is a schematic diagram of the power supply structure of the DC power supply system of the present invention, which is powered by a three-phase AC power source through a voltage regulator. Figure 3 This is a schematic diagram of another power supply structure in the DC power supply system of the present invention, in which a three-phase AC power supply is regulated by a voltage stabilizer. Figure 4 This is a schematic diagram of the resonant converter circuit involved in the present invention; Figure 5 This is a schematic diagram of another resonant converter circuit according to the present invention. Detailed Implementation

[0031] See Figures 1 to 5 The voltage stabilizing device involved in this invention consists of several voltage stabilizing modules and can be mainly used in DC uninterruptible power supplies or DC power distribution systems for wind power, solar power generation and power transmission and distribution grid systems. It realizes automatic adjustment of voltage output, ensures the safety and reliability of operating equipment such as power stations and power grids, achieves voltage safety and stability, and prevents damage to the operating equipment due to voltage fluctuations / excessive or insufficient voltage.

[0032] In the example of a voltage regulator (voltage regulator cabinet) product involved in this invention, the voltage regulator consists of 8 standardized voltage regulator modules, which are connected in parallel to each other, with a constant voltage output of 110V. The output current of each module is 40A, totaling 320A.

[0033] See Figure 1 Under normal operating conditions, the input voltage of the voltage regulator circuit is affected by the equalization and float charging state of the battery. Taking a DC 110V system using commonly used nickel-cadmium batteries as an example, the output voltage of the charging circuit is in the range of 129-139V (equalization and float charging state). If the AC input side of the charging circuit is de-energized, the charging circuit has no output, and the DC bus directly (without DC / DC converter circuit) connected to the battery (energy storage circuit) (e.g.) Figure 1 In the example, the closing bus voltage is equal to the battery voltage. In this case, the energy storage circuit (battery, or energy storage battery) should continuously discharge. When the energy storage battery discharge voltage drops below 110V, even to 90V, if it is desired that the relevant DC bus (e.g., Figure 1 In the example, the control bus voltage is maintained at 110V, requiring a boost. Therefore, a voltage regulator circuit with both buck and boost capabilities should be installed, connected in series between the battery and the DC bus requiring voltage regulation (e.g., ...). Figure 1 In the example, between the control bus and the voltage bus, the voltage connected to the corresponding DC bus is stabilized at the set constant voltage output (within the allowable range of constant voltage output) through the step-down or step-up voltage regulation circuit.

[0034] The DC / DC converter circuit in the voltage regulator module can use a resonant converter (e.g., an LLC converter) or any other suitable DC / DC converter circuit. The voltage output range can be set according to actual needs, for example, adjustable from 88V to 160V. Under a standardized modular design, an appropriate number of voltage regulator modules can be connected in parallel based on current output requirements to form the required power (current) output capacity. For example, for a 40A voltage regulator module, if the current requirement is 200A, five voltage regulator modules can be selected. If necessary, a certain degree of redundancy can be set, such as N+1 redundancy. Because the voltage regulator modules are connected in parallel, the failure of one module will not affect the power supply of other modules. Compared to silicon chain buck converters, this modular voltage regulator not only has buck and boost functions, but is also easy to install, occupies little space, generates little heat, can be used in large capacities, and has a high safety factor.

[0035] See Figure 2 and Figure 3 A power supply circuit that uses three-phase alternating current as the primary power source and then regulates it to produce DC output includes: 1) Input protection unit It can mainly include an EMC circuit composed of EMC common-mode and differential-mode inductors and X capacitors and Y capacitors, a varistor discharge tube, and an input over / under voltage and phase loss judgment circuit. The input is AC power (from the power grid), and the output is protected AC power connected to the input side of the bridge rectifier unit.

[0036] Function: Prevents damage to subsequent circuits caused by input overvoltage, overcurrent, surge, etc.

[0037] Operating mode: When the input voltage is too high, the current is too large, or a surge occurs, protection is provided by devices such as fuses, varistors, and thermistors.

[0038] 2) Bridge rectifier unit A full-bridge three-phase rectifier bridge built with high-voltage rectifier diodes can be used, with the output being pulsating DC power, which can be connected to the PFC unit.

[0039] Function: Converts alternating current (AC) to direct current (pulsating DC).

[0040] Operating mode: Full-wave rectification is performed using a diode bridge rectifier.

[0041] 3) Passive PFC unit Any suitable passive PFC circuit or other suitable form of PFC circuit can be used. For example, it consists of a PFC inductor, a high-frequency filter capacitor, and a fast recovery diode. The input terminal of the PFC inductor is connected to the positive output of the bridge rectifier unit, and the output terminal is connected to the first smoothing filter unit (the positive terminal of the capacitor) through the fast recovery diode. One end of the high-frequency filter capacitor is connected at the node between the PFC inductor and the fast recovery diode, and the other end is grounded.

[0042] Functions: Improve power factor, reduce high-frequency harmonics, etc.

[0043] Operating principle: It suppresses current spikes and improves the power factor through a power storage inductor (PFC inductor); prevents reverse current through a fast recovery diode; and absorbs switching noise through a bypass capacitor (high-frequency filter capacitor), making the input current waveform closer to a sine wave to reduce harmonic pollution. In practical industrial applications, it can improve the power factor to 0.7–0.9. Compared to traditional rectifier filters, passive PFC has a simple structure, low cost, and high reliability, and is mainly suitable for low- to medium-power applications.

[0044] 4) First smoothing filter unit It primarily uses high-voltage electrolytic capacitors, along with passive PFC inductors, to form a filter circuit, providing a relatively smooth DC voltage to the DC / DC converter unit (or DC / DC unit). Its output is a relatively stable DC voltage, which is then connected to the DC / DC converter unit.

[0045] Function: Smooths pulsating direct current into a more stable direct current.

[0046] Operating mode: It forms an LC filter circuit with the inductor of the passive PFC to filter and reduce ripple or pulsation.

[0047] 5) DC / DC conversion unit Any suitable DC / DC converter circuit can be used, such as LLC, SRC, LCC, or ZVS-MR resonant DC / DC converter units, to achieve DC / DC conversion and obtain the required voltage. Depending on the specific circuit configuration, voltage reduction or boosting can be achieved through control methods such as frequency control and / or pulse width control of the DC / DC switching transistors, thereby controlling and adjusting the output voltage. For example, when the output voltage is higher than the set output voltage (output side voltage), the required constant voltage output is achieved by stepping down; when the input voltage is lower than the set output voltage, the required constant voltage output is achieved by boosting. The DC power input to the DC / DC converter unit can originate from three-phase AC power, such as the three-phase AC output of a wind or solar power system, which is then rectified and filtered to form a relatively stable DC power (see...). Figure 1 and Figure 2 ), or it can originate from energy storage circuits (see Figure 1 The DC / DC converter outputs a DC power that meets the voltage requirements. The circuit configuration on the output side of the DC / DC converter unit can be customized based on actual conditions; for example, it can be filtered (e.g., ...). Figure 2 The second smoothing filter unit in the example is connected to the control bus or other corresponding DC bus.

[0048] 6) Second smoothing filter unit The same or similar method as the first smoothing filter unit can be used, such as setting an electrolytic capacitor as the filter capacitor for filtering, or using an LC filter circuit, etc.

[0049] 7) Control loop unit A resonant voltage-type dual-loop control circuit can be used, consisting of a voltage loop (outer loop) and a current loop (inner loop), located in the DC / DC conversion stage (DC / DC conversion unit). Its voltage feedback signal (V_fb) comes from the output voltage divider resistor, and current sampling is achieved through a current transformer connected in series with the primary winding of the transformer. Using dual-loop control improves dynamic response and stability. The resonant switching transistor switches under zero-voltage or zero-current conditions, significantly reducing switching losses and EMI, and improving efficiency (up to 92% or more) and reliability.

[0050] Function: Controls the switching frequency and / or duty cycle of the DC / DC converter to achieve stable output and soft switching.

[0051] Overall, the control loop receives control signals from the microprocessor and voltage and current signals from feedback sampling, and outputs drive signals for the switching transistors. These drive signals control the switching transistors of the DC / DC converter, thereby achieving voltage regulation and current limiting.

[0052] 8) Voltage Regulator Employing a microprocessor and corresponding auxiliary facilities, it features display and communication functions. It mainly includes: a microprocessor, serving as the core controller for data processing and logic control; a digital tube driver chip (such as 74HC595), providing an expanded display interface; an RS-485 level conversion chip, such as MAX485, to convert serial signals into RS-485 differential signals; and voltage divider resistors and filter capacitors for feedback sampling and interference suppression.

[0053] Basic functions: Monitor power supply / circuit status, and implement digital control, communication, display, and protection logic.

[0054] Operating mode: Based on the input signal and preset algorithm, data processing is performed to generate control signals, realizing the regulation, protection, display, and communication of output voltage / current. Inputs: Signals from feedback sampling, over-temperature protection signals, over-voltage, over-current, and short-circuit protection signals, key and DIP switch settings, RS-485 communication, etc.; Outputs: Control signals to the resonant voltage type dual-loop control circuit, display signals to the digital tube, communication signals to RS-485, and current sharing control signals, etc.

[0055] Microprocessors (such as STM32) can acquire output voltage / current signals via ADC pins and control the digital tube display and key input via GPIO. The RS-485 interface connects to an external communication bus via a MAX485 chip. DIP switches set the address or operating mode.

[0056] Intelligent management can be achieved through a microprocessor, which can monitor output status, control protection logic, support remote communication (RS-485), and human-machine interaction (display and settings). It has flexible parameter settings, fault recording, remote monitoring and other functions, which helps to improve the intelligence level and maintainability of the system.

[0057] Depending on actual needs, a host computer can be configured to communicate with the microprocessor (see [link]). Figure 3 Relying on the processing power of the host computer to make predictions and set output targets and control parameters, the processing can be reasonably allocated between the host computer and the microprocessor based on existing technology, taking into account processing power, processing speed, communication time and response speed. Under the existing technology background, the monitoring unit (monitoring system) of the DC power supply can be used as the host computer to perform related functions.

[0058] When appropriate, a microprocessor with corresponding data processing capabilities can also be set up to perform the above data processing.

[0059] Various signal / data acquisition / acquisition methods can be flexibly set according to actual conditions. For example, the output (voltage, current) of the charging circuit can be detected in real time, and the working status of the charging device / charging circuit can be determined based on the output voltage and current. For example, when there is current (the normal range of current output can be determined based on experience), the voltage output can be used to determine whether it is a float charging state or an equalization charging state; when there is voltage, if the current is zero, it is a blocked state.

[0060] Various signals related to the charging device, energy storage device, and load can be obtained from the charging controller, load, and / or DC power supply monitoring unit, such as the real-time stored energy of the energy storage circuit, bus (each bus) voltage, and bus (each bus) current.

[0061] The required remote data can be extracted from the sending end, receiving end, or communication link of the remote data.

[0062] 9) Flow equalization control unit This design is suitable for applications where multiple voltage regulator modules are connected in parallel and current sharing is required. By sampling and comparing the output current of each module, the current sharing controller adjusts its output voltage to ensure that each module shares the load current proportionally. This design supports N+1 redundancy, improving system reliability, and is suitable for high-current or multi-module parallel applications.

[0063] 10) Protection Unit Overvoltage, overcurrent, and short-circuit protection unit: Used to prevent damage to the load caused by output overvoltage, overcurrent, short circuit, and other faults. It is implemented through overvoltage protection, overcurrent protection, and short-circuit protection circuits (which may include comparators, thyristors, etc.). Its input is DC power from smoothing filters, and its output is protected DC power, which serves as the DC output of the power supply.

[0064] Over-temperature protection unit: The heat sink is mounted on a thermistor RT1, and the change in its resistance triggers a protection signal via comparator U3.

[0065] The system employs a multi-level protection mechanism to monitor temperature, voltage, and current in real time. In the event of an anomaly, the output is immediately shut off to prevent damage to downstream equipment. The protection response time is fast (<10μs), and it offers selectable self-recovery or latching modes, enhancing system safety.

[0066] 11) Current sharing control or distribution unit between power sources (where appropriate) In the case of multiple power supplies connected in parallel, the output current of each power supply is balanced. Its input is the sampling signal of the output current of the local power supply and the current sharing signal from other power supplies (via RS-485 or other current sharing bus). By comparing the local current and the average current, the output adjustment signal is used to adjust the local output to make the current consistent.

[0067] Figure 4 An example of a single-capacitor half-bridge ZVS resonant circuit used as the DC / DC converter unit of this invention is shown. Its operation is as follows: In the first half-cycle, S1 is on, and S2 is off. The Vin+ voltage charges Cr through S1, Lr, and T. The primary voltage of the transformer is Vin-VCR, and the transformer outputs energy. When S1 is off, the sinusoidal current has not yet returned to zero and still possesses a certain amount of energy, sufficient to induce a left-negative, right-positive flyback voltage across Lr. This charges C1 and discharges C2, eventually bringing S2 to a zero-voltage condition. Turning on S2 initiates the second half-cycle. The high-frequency, brief resonance generated by Lr with C1 and C2 softens the switching process. In the second half-cycle, the energy stored on Cr forms a left-positive, right-negative flyback voltage through S2, Lr, and T, inducing a brief high-frequency resonance between Lr and C1 and C2, charging C2 and discharging C1, causing S1 to conduct under zero-voltage conditions, thus beginning a new cycle. Similarly, S1 and S2 are turned off at zero voltage under the protection of C1 and C2 buffers.

[0068] Figure 5 An example of a multi-resonant circuit (ZVS-MR resonant type) used as the DC / DC converter unit of this invention is shown. Its basic construction is... Figure 4Based on the example, the secondary-side filter inductor is removed, resulting in a novel converter circuit. This circuit not only achieves zero-voltage soft-switching of the primary main switch but also zero-current turn-off of the secondary rectifier diode. Its operation is as follows: In the first half-cycle, S1 begins to conduct, S2 is off, and the voltage VCR (Cr) is low. Ignoring the voltage drop of Lr during operation, the transformer primary is at its maximum excitation voltage Vin - VCR. The secondary diode D1 conducts, rectifying to Vo. The primary-side current Ip is determined by the resonance of Lr and Cr, and is a sine wave. As the VCR charging voltage increases, the transformer primary resonant current rises to its peak value and then decreases. When the voltage across the primary side decreases to n1 / n2*Vo as VCR increases (n1 and n2 are the number of turns in the primary and secondary windings of the transformer, respectively), D1 naturally cuts off due to zero current. After this, due to the cutoff of D1, the transformer is isolated from the load, and the primary side exhibits a large inductance Lm (Lm is the primary magnetizing inductance; when the transformer is under load, its value is not reflected because it is connected in parallel with a very small coupling load resistance from the secondary side). At this time, due to the presence of a large inductance Lm, the primary current Ip immediately changes its rate of decrease, becoming a sinusoidal wave with a very low resonant frequency determined by Cr and Lm+Lr (sine curve). Since Lm is very large, the value of Ip is very small at this time, and the change is extremely slow. On the waveform diagram, it is approximately a horizontal line, which is maintained until the end of the first half of the cycle, Ton. The energy used to soften the S1 and S2 switches at the end of the first half of the Ton cycle comes from this "horizontal line" current. The value of the "horizontal line" current can be precisely designed and should be just right. Too little current is insufficient for the zero-voltage resonant switch, while too much will increase conduction losses and even cause other unnecessary problems. Throughout the entire circuit operation, the end of the first half of the Ton (conduction time) almost always falls on this "horizontal line". Due to the symmetry of the circuit, in the second half of the cycle, when S1 is off and S2 is on, Cr, which is at a high voltage, discharges through T, Lr, and S2. The secondary side D2 conducts rectification, and first Lr and Cr resonate, and then naturally cut off at zero current, starting the low-frequency resonance process of Lm+Lr and Cr until the end of the second half of the cycle. There are three resonance processes in the operation of this circuit: (i) the loaded resonance process, formed by Lr and Cr; (ii) the unloaded resonance process, formed by Lr and C1+C2; and (iii) the ZVS soft-switching resonance process, formed by Lr and C1+C2. It is the combined effect of these three resonant processes that enables both the switching transistor and the secondary rectifier to operate under soft-switching conditions. Therefore, this circuit can be called a multi-resonant circuit, and its electronic switch can be called a multi-resonant switch.

[0069] The operation control of each of the above resonant DC / DC converter units is frequency modulation, referred to as frequency regulation. Compared to PWM circuits, it has the following characteristics: 1) The circuit is extremely simple, with the fewest switching components and the least conduction loss. It does not require any RC noise reduction or absorption components, and it does not even require no-load "dead load". 2) It has the strongest load-bearing capacity, with a single unit output power reaching tens of kilowatts or more; 3) Highest conversion efficiency: The full-load efficiency of the three-phase input 48V 100A communication power supply can exceed 96%; 4) Due to its high efficiency, the temperature rise is low, requiring a small heat sink; 5) Includes high-frequency rectification, ensuring the circuit never loses its soft-switching capability, eliminates Miller interference, and guarantees safe operation; 6) The sinusoidal operating current has low harmonic content, resulting in low harmonic loss and interference; 7) The power supply is small in size and light in weight; 8) Power supply voltage clamping, the switching transistor does not need to withstand high voltage.

[0070] Given the existing technology, the following designs can be used to give the voltage regulator / DC power supply the following characteristics: 1) It adopts digital control technology, with meticulous logic, reliable control, and rapid sampling protection; 2) It adopts isolated autonomous current sharing, and the uneven current sharing between parallel units is less than ±5%, with strong compatibility; 3) Natural cooling and heat dissipation, low noise, and adaptable to harsh dusty environments; 4) It has an RS-485 interface, which facilitates communication with automation systems; 5) The droop-down current limiting method is adopted, which reduces short-circuit losses and enhances reliability; 6) Employ loop control technology, such as dual-loop PI (or PID) control technology, achieving a conversion efficiency of over 96%; 7) The module has a built-in LED digital display and setting buttons, enabling operation of the main body; 8) The design is compact and small in size, allowing multiple modules to be used in parallel, enabling high-current operation in a small space; 9) Multiple input and output protection functions are designed, and the module has a soft-start function; 10) Built-in DC output isolation diode to prevent reverse current transmission; 11) The operation indicator light is used to indicate the equipment's operating status, the charge / discharge indicator light is used to indicate the equipment's charging / discharging status, and the fault indicator light is used to indicate the equipment's fault status. 12) It has a hot-swappable function, fully considering the need for easy replacement and convenient and reliable maintenance; 13) The error correction design of the traditional module plug-in terminal protects the safety of the system front-end and the main body equipment.

[0071] Based on functionality, ease of use, and ease of assembly, the aforementioned circuit units can be integrated into different modules, such as charging modules, energy storage modules, and voltage regulator modules. For example, a charging module can be formed by integrating a mutually complementary input protection unit, bridge rectifier unit, passive PFC unit, and first smoothing filter unit; a battery module can be formed by integrating several batteries; and a voltage regulator module can be formed by integrating a mutually complementary DC / DC converter unit, second smoothing filter unit, corresponding control loop unit, microprocessor unit, current sharing control unit, and various protection units. According to the DC power supply requirements, voltage regulator modules, energy storage modules, and charging modules can be rationally configured in the DC power supply system, and the number of each module can be rationally selected. In particular, for voltage regulator modules, an N+1 redundancy design can be used. Each voltage regulator module can be connected in parallel to form the required power output capacity; each charging module can be connected in parallel to form the required charging capacity; and each energy storage module can adopt an appropriate connection method according to actual needs to form the required energy storage capacity and output voltage. When necessary, a host computer can be equipped to communicate with each microprocessor. Data processing that is difficult or unsuitable for microprocessors to perform can be performed by the host computer, and the processing results can be sent to the corresponding microprocessor, which will then forward them to the corresponding drive / actuator.

[0072] Based on existing technology, this system implements battery charging and discharging management and switches the input power supply (three-phase AC or energy storage unit) of the DC / DC converter unit, configuring corresponding control circuits and signal acquisition circuits. Under normal conditions of the original power supply (three-phase AC), the charging circuit, under the control of the charging controller (composed of one or more charging modules), outputs equalization charging voltage or float charging voltage according to the battery status, performing equalization charging or float charging on the battery. Simultaneously, the DC output of the charging circuit is connected to a voltage regulator circuit (composed of one or more voltage regulator modules, or a voltage regulator device), serving as the input power supply for the voltage regulator circuit. When the input side of the charging circuit is disconnected or the original power supply (three-phase AC) fails, the voltage regulator circuit (DC / DC converter unit) switches to the energy storage circuit (composed of one or more energy storage modules, or an energy storage device), obtaining electrical energy through battery discharge. Related control and switching can be achieved using existing technology.

[0073] Based on existing technology, a dual-loop control structure (or dual-loop control circuit) for voltage and current is set up in the DC / DC converter unit. The PFM control module (PFM modulator) in the dual-loop control circuit sends drive signals to the DC / DC switching transistors according to the control command signals of the dual-loop circuit (e.g., the conduction time command Ton sent from the current loop). These signals are amplified and connected to the corresponding switching transistors to control the DC / DC converter circuit and obtain the required constant voltage output. When necessary, the microprocessor or host computer dynamically adjusts the dual-loop control parameters (typically including the current loop proportional gain Kp_i, current loop integral gain Ki_i, voltage loop proportional gain Kp_v, and voltage loop integral gain Ki_v) based on the predicted bus load (load on the corresponding DC bus) and input electrical quantities (e.g., voltage) to achieve good voltage regulation when the load changes significantly. When a significant load change is predicted, the number of voltage regulator modules is adjusted, and the modules are switched on and off to adapt the output capability of the voltage regulator circuit to the load requirements.

[0074] The prediction model is adapted to the processing power of the microprocessor or host computer. When the microprocessor does not have sufficient processing power or when appropriate, a host computer can be provided to send the corresponding sampled data (model input data) to the host computer for prediction.

[0075] Based on the variation range of the bus load (closing bus and control bus) (and, where appropriate, the load change rate range), and the variation range of the energy storage circuit (battery bank), several sets of feedback control parameters (which can be called feedback control parameter sets) are set. Each set of feedback control parameters corresponds to (is suitable for) a certain bus load range and energy storage range, and a corresponding set of feedback control parameters can be found for any combination of bus load and energy storage (within the relevant variation range). For example, the variation range of the bus load is divided into several small load zones (ranges), with adjacent small zones preferably overlapping. The variation range of the energy storage is divided into several small energy storage zones, with adjacent small zones preferably overlapping. Each small load zone is paired with all small energy storage zones, forming several multi-factor (two-factor) small zone combinations of each small load zone and each small energy storage zone. A suitable set of feedback control parameters is pre-set for each small zone combination. When it is necessary to consider the load change rate simultaneously (since considering the load change rate helps improve control accuracy but increases data processing volume, it can be considered or not considered depending on actual needs), small load change rate partitions are divided in the same way, and several three-factor small partition combinations are formed by pairing them. A set of feedback control parameters is preset (tuned) and stored for each multi-element small partition combination. In the state of charging circuit blocking, the voltage regulator controller retrieves / reads the feedback control parameters of the corresponding small partition combination based on the predicted / measured values ​​of factors such as bus load, load change rate (when needed), and energy stored in the energy storage circuit, so as to adjust the feedback control parameters of the DC / DC conversion unit (when needed). The above-set (tuned) feedback control parameters are used as the preset feedback control parameters for the corresponding state (small partition). In the actual control process, the (set) feedback control parameters are used as the preset feedback control parameters for the small partition where the predicted DC bus load (or the predicted DC bus load and linear bus load change rate) and the real-time energy stored in the energy storage circuit are located at the corresponding time.

[0076] In both floating charge and equalizing charge states, the voltage regulator does not need to predict the bus load or detect the energy stored in the energy storage circuit. Instead, it can directly retrieve / read the feedback control parameters set for that state to adjust the feedback control parameters of the DC / DC converter (when necessary).

[0077] When dividing the load into small zones, the entire bus load range should be covered (the entire range involved in the corresponding application scenario, the same below), and it is preferable that adjacent small zones partially overlap. The same applies to the division of small zones for other factors (energy storage circuit energy storage, bus load change rate). When the values ​​of each factor fall within the overlapping area of ​​the current small zone combination and adjacent small zone combinations, the feedback control parameters are not adjusted; when the values ​​of each factor fall within the overlapping zone of multiple small zone combinations outside the current small zone combination, the feedback control parameters are adjusted to the feedback control parameters adjacent to the current small zone combination or to use the feedback control parameters among the multiple overlapping small zones that are closest to the current feedback control parameters, in order to avoid over-adjustment (including being too large or too small) and maintain output stability.

[0078] The size of each sub-zone is determined based on actual needs and can be experimentally determined for each factor (small bus load zone, small bus load change rate zone, small energy storage zone). For the same factor, the size of each sub-zone can be consistent or inconsistent. For example, when only small load zones need to be divided, multiple detection points can be evenly selected across the entire load change rate range. The current dual-loop control parameter setting method can be adopted to set feedback control parameter groups (preliminary setting) at each load value, obtaining the numerical distribution pattern of the preliminary set feedback control parameter groups at each detection point. Based on this distribution pattern, several adjacent (numerically adjacent or with similar control effects) and not too dense (appropriate number) feedback control parameter groups are determined, so that the control effects of adjacent feedback control parameter groups in the overlapping area (within a satisfactory or acceptable range) are similar and similar to their control effects in their respective central areas. If necessary, the control effect of each feedback control parameter group in its corresponding sub-zone can be verified experimentally. Based on the control effect, the number of sub-zones, the range of each sub-zone, and / or the feedback control parameters of each sub-zone are adjusted to ultimately obtain satisfactory or acceptable results. When using a combination of multiple factors in small sub-regions, verification and adjustment can be carried out in a similar way. Several evenly distributed spatial points are selected in the multidimensional space composed of multiple factors, and the above verification, adjustment and tuning are carried out.

[0079] The data in the prediction data record is set according to actual needs and computing power. For example, it can be or may include: wind turbine generator operation data (e.g., start-up / standby / shutdown status, turbine rotor speed, blade angle, yaw angle, output voltage, current, active power, reactive power), secondary equipment operation data (e.g., operation / status data of main controller, pitch controller, yaw controller, various sensors, relay protection devices, and communication equipment), wind direction and speed data, and SCADA command data, etc. The four remote sensing data (partial or complete) can be obtained from SCADA (e.g., SCADA communication interface) or from the wind turbine generator's main control system and related secondary equipment, and some or all of the four remote sensing data can be used as prediction data. For example, a preferred implementation is to use rotor speed, blade angle, yaw angle, (power generation output) voltage, current, active power, reactive power, and wind direction and speed as prediction data. If necessary, bus voltage and current (or the voltage-to-current ratio) can also be included in the prediction data. These data and their changes (time-series changes) basically determine the operating and power consumption status of secondary equipment (especially the control loads), and can effectively predict the bus load and its rate of change.

[0080] Depending on the actual situation, the above data can also be adjusted, added, deleted, or supplemented through technical analysis and / or experiments, or other data can be selected as the output data of the prediction model.

[0081] Historical data acquired / recorded by a DC power supply monitoring unit (or monitoring system) or SCADA (Supervisory Control and Data Acquisition) system can be used as sample data for model training. If necessary, experimental data and / or relevant data from other sources can also be used or supplemented. For example, data used as model input data and bus voltage (DC bus voltage) and bus current (DC bus current) used for model output data calculation can be extracted from SCADA's remote sensing data. The bus load is calculated based on the bus voltage and current. The bus load change rate is calculated based on the bus load at any given time (e.g., time t) and the previous time (e.g., time t-1). The model output data (or target value) in the sample data is the bus load at that time or the bus load and bus load change rate at that time. Prediction data records (e.g., 6-10 records) from several consecutive times preceding that time are used as model input data in the sample data, forming the sample data. When using remote sensing data, these sample data can be automatically generated by developing corresponding software.

[0082] If necessary, hardware detection can also be used to detect relevant information from the relevant DC bus, charging circuit, charging controller and related load. Data sampling and conversion can be performed through the matching interface (sampling) circuit to form relevant data that can be processed by the voltage regulator or other data processing devices.

[0083] Relational databases (or relational databases) can be used to store sample data or other data (including small partition combinations and corresponding feedback control parameters), or other methods can be used depending on the specific form of the data. When storing data in a relational database, related datasets at the same sampling / detection point (or moment, or time point) can be grouped into a single data record, recorded as a row in the database / table. During model training and prediction, the corresponding data records or corresponding data from data records are extracted from the database. For example, during model training (including validation), the bus load or the bus load and bus load change rate (or the bus voltage and current can be extracted and calculated) at the corresponding moment can be extracted from the database as the model output data (target value) in the sample data at that moment. The M consecutive prediction data records that are first (adjacent) in time can be extracted as model input data in the sample data, forming a sample dataset. The required number of sample datasets can be extracted according to actual needs, and the dataset can be divided into training, validation, and test sets according to conventional methods for model training, validation, and testing. The test set also uses recent data.

[0084] The data recording sequence used for prediction is typically an equidistant sequence. The time interval or sampling period of the data recording sequence for prediction can be determined based on prediction and control requirements (e.g., 1 second, 0.5 seconds). When the sampling interval (sampling period) of the raw data, or the time interval of the detection data recording sequence, is less than the time interval of the prediction data recording sequence, the required data can be extracted from the detection data recording sequence corresponding to the prediction data recording sequence (at the same time point) and used as the corresponding data in the prediction data recording. If the acquisition interval of the raw data, or the time interval of the detection data recording sequence, is greater than the time interval of the prediction data recording sequence (e.g., wind speed), the nearest neighbor data can be used.

[0085] Model training can follow the conventional training methods for LSDT models. For example, data cleaning and normalization / standardization can be performed according to actual needs. A two-layer LSTM can be selected, with the first layer having 128 or 64 neurons and the second layer having 64 or 32 neurons. The stride can be 30. The output nodes of the fully connected output layer are set according to the prediction target. The root mean square error (RMSE) is used as the loss function, and the Adam optimizer is used to iteratively update the network weights.

[0086] The prediction model can be updated based on new detection data records. New sample data is constructed using the new detection data (which may include some old detection data, if necessary), and the existing prediction model is retrained. Before the prediction model update is complete, predictions can be made based on the original prediction model, avoiding any hindrance to prediction and control due to model updates.

[0087] The number of voltage regulator modules can be adjusted based on the predicted DC bus load, with each module connected in parallel. The load is divided into several levels, from light load to heavy load, for example, light load, constant load, and heavy load. When the predicted bus load falls into the next level (the next level below the current load level), one voltage regulator module is disconnected; when the predicted bus load rises into the next level (the level above the current load level), one voltage regulator module is added.

[0088] The ranges of adjacent load levels are preferably partially overlapping. When in the overlapping area (for example, light load is 0-40% of the variable range, normal load is 30-70% of the variable range, and heavy load is 60-100% of the variable range, with the variable range of load determined according to the actual situation), the currently engaged voltage regulator module should remain unchanged to avoid continuous switching due to fluctuations at the boundary line when the load level is near the boundary line between the two levels.

[0089] Based on the remaining lifespan (duration), output stability, and / or temperature (temperature rise) of the voltage regulator modules, prioritize the activation of voltage regulator modules with long remaining lifespan, low temperature rise (under long-term operating conditions), or good stability, and prioritize the deactivation of voltage regulator modules with short remaining lifespan, high temperature rise, or poor stability, in order to maintain overall stability and reliability.

[0090] Unless otherwise specified, the preferred and optional technical means disclosed in this invention can be arbitrarily combined to form several different specific embodiments when one preferred or optional technical means is a further limitation of another technical means.

Claims

1. A modular voltage stabilizer provided with a voltage stabilizing circuit and a voltage stabilizing controller, characterized in that The voltage regulator circuit adopts a modular design, consisting of several voltage regulator modules connected in parallel. Each voltage regulator module includes a DC / DC converter and an output-side smoothing filter connected to the output side of the DC / DC converter. The input terminal of the voltage regulator module is used to connect to the energy storage circuit connection terminal and the charging circuit output terminal, while the output terminal is used to connect to the control DC bus. The DC / DC converter has a feedback control circuit. The voltage regulator controller controls the feedback control parameters of the DC / DC converter to ensure that the output of the voltage regulator circuit is a set constant voltage output. The voltage regulator controller acquires / obtains the operating status of the charging circuit on the input side of the voltage regulator circuit and sets the feedback control parameters of the DC / DC converter unit in the following manner: 1) If the charging circuit is in float charging mode, use the corresponding setting feedback control parameters for that mode; 2) If the charging circuit is in the equalization charging state, the corresponding feedback control parameters for that state shall be used; 3) If the charging circuit is in a locked state, based on the prediction model, the DC bus load is predicted, and the feedback control parameters for the corresponding time are set to preset feedback control parameters corresponding to the predicted DC bus load and the real-time energy storage of the energy storage circuit; or, based on the prediction model, the rate of change of the DC bus load and the linear bus load is predicted, and the feedback control parameters for the corresponding time are set to preset feedback control parameters corresponding to the predicted DC bus load and the linear bus load rate of change and the real-time energy storage of the energy storage circuit.

2. The modular voltage regulation device of claim 1, wherein The feedback control circuit of the DC / DC converter unit adopts a dual-loop control circuit. The feedback control parameters of the feedback control circuit include the proportional gain of the current loop, the integral gain of the current loop, the proportional gain of the voltage loop, and the integral gain of the voltage loop.

3. The modular voltage regulation device of claim 2, wherein The DC / DC converter unit adopts a resonant DC / DC converter unit adapted to PFM signal control. The dual-loop control circuit is equipped with a PFM control module. The PFM control module sends out drive signals to the DC / DC switching transistors according to the control command signals of the dual-loop circuit. The DC / DC switching transistors are controlled through the PFM drive signals to obtain the required constant voltage output.

4. The modular voltage regulation device of any one of claims 1-3, wherein Both the input and output sides of the voltage regulator module are equipped with switching switches. The switching switches on the input and output sides of the same voltage regulator module are linked. The voltage regulator controller controls the state of the switching switches of each voltage regulator module according to the predicted or measured value of the control load.

5. A control method for a modular voltage stabilizer, the modular voltage stabilizer employing a voltage stabilization circuit based on a DC / DC conversion unit, the input end of the DC / DC conversion unit being connected between the storage circuit connection end and the charging circuit output end, the DC / DC conversion unit being provided with a feedback control circuit, and the voltage stabilization controller being configured to control the feedback control parameters of the DC / DC conversion unit so as to make the output of the voltage stabilization circuit a set constant voltage output, characterized in that The voltage regulator controller acquires / obtains the operating status of the charging circuit on the input side of the voltage regulator circuit, and sets the feedback control parameters of the DC / DC converter unit in the following manner: 1) If the charging circuit is in float charging mode, use the corresponding setting feedback control parameters for that mode; 2) If the charging circuit is in the equalization charging state, the corresponding feedback control parameters for that state shall be used; 3) If the charging circuit is in a locked state, based on the prediction model, the DC bus load is predicted, and the feedback control parameters for the corresponding time are set to preset feedback control parameters corresponding to the predicted DC bus load and the real-time energy storage of the energy storage circuit; or, based on the prediction model, the rate of change of the DC bus load and the linear bus load is predicted, and the feedback control parameters for the corresponding time are set to preset feedback control parameters corresponding to the predicted DC bus load and the linear bus load rate of change and the real-time energy storage of the energy storage circuit.

6. The control method of the modular voltage stabilizing device according to claim 5, characterized by The prediction model used is an LSTM prediction model obtained by training an LSTM neural network.

7. The control method of the modular voltage stabilizing device according to claim 6, characterized by The DC bus load uses the equivalent load resistance.

8. The control method of the modular voltage stabilizing device according to claim 6, characterized by The output data of the prediction model is the DC bus load, or the DC bus load and the DC bus load change rate. The input data of the prediction model is a series of consecutive prediction data records with the time sequence preceding the input data.

9. New energy power DC power supply system, including: The charging device is equipped with a charging circuit and a charging controller. The charging circuit is used to convert three-phase AC power into DC power under the control of the charging controller. Its input side is connected to three-phase AC power and its output side is connected to the DC bus. The energy storage device uses a battery as the energy storage element, and its connection terminal is connected to the output side of the charging circuit. A voltage regulator is used to convert the input DC power into a constant voltage output. The input terminal of the voltage regulator module is connected to the energy storage circuit connection terminal and the charging circuit output terminal, and the output terminal of the voltage regulator module is connected to the control DC bus. Its features are, The voltage regulator is a modular voltage regulator as described in any one of claims 1-4, and / or the control method of the voltage regulator is a voltage regulator control method as described in any one of claims 5-8.

10. The new energy power DC power supply system of claim 9, wherein The output side of the charging circuit is connected to the control DC bus via a switching switch.

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