A single-input multiple-output modular multi-port power supply and a control method thereof

Abstract

The application discloses a single-input multi-output modular multi-port power supply and a control method thereof. The power supply comprises an AC-DC conversion module, a first DC conversion module comprising a plurality of parallel first DC conversion units for providing an output in a four-quadrant operation mode, a second DC conversion module comprising a plurality of parallel second DC conversion units for providing an output in a two-quadrant operation mode, and a third DC conversion module comprising a plurality of parallel third DC conversion units for providing an output in a single-quadrant operation mode. The input ends of the first DC conversion module, the second DC conversion module and the third DC conversion module are connected in parallel to a DC bus at the output end of the AC-DC conversion module. The control method performs collaborative optimization of voltage loop control parameters, current loop control parameters and power distribution coefficients by using a multi-objective evolutionary algorithm. The application effectively improves the flexibility, expandability and stability of the multi-port modular power supply.

Description

Technical Field

[0001] This application relates to the field of power control technology, and in particular to a modular multiport power supply with single input and multiple outputs and its control method. Background Technology

[0002] With the widespread application of multi-port power supplies in test benches, scientific research equipment, and multi-load power supply scenarios, the demand for powering multiple DC outputs from a single AC input is increasing. Its development and application have profoundly impacted various fields such as consumer electronics, industrial equipment, and new energy vehicles. In multi-load power supply scenarios, it is often necessary to provide power to multiple different types of loads from a single AC input.

[0003] However, most existing multi-port power supply architectures use a uniform topology to achieve output from multiple ports. While this approach can meet basic energy distribution requirements, it suffers from significant deficiencies in flexibility and struggles to meet diverse load demands. Different loads often have varying requirements during operation. For example, some loads require bidirectional voltage and current regulation as well as energy feedback, necessitating four-quadrant operation of the power supply ports; others only require unidirectional energy output, which can be met by a two-quadrant or single-quadrant topology. If existing solutions uniformly adopt a complex four-quadrant circuit structure, it can easily lead to excessively high overall costs and losses; if only a simple single-quadrant or two-quadrant structure is used, it cannot meet complex requirements, thus limiting applications. Furthermore, when faced with multiple loads operating under different conditions simultaneously, traditional power supply topologies struggle to balance efficient energy transfer, flexible expansion, and stable operation, often requiring the design of dedicated power supplies, increasing system complexity and maintenance costs. Summary of the Invention

[0004] To address the above technical issues, this application provides a modular multi-port power supply with single input and multiple outputs and its control method, which can provide single-quadrant, two-quadrant, and four-quadrant operating conditions with a wide voltage regulation range, and can meet different load characteristics and operating requirements by flexibly configuring different power supply modules.

[0005] This application provides a modular multi-port power supply with single-input multiple-output, including:

[0006] An AC-DC converter module is used to convert three-phase AC input into DC output;

[0007] The first DC-DC converter module includes several parallel first DC-DC converter units for providing output in a four-quadrant operating mode; the first DC-DC converter unit includes a dual active bridge and a first H-bridge.

[0008] The second DC-DC converter module includes several parallel second DC-DC converter units for providing output in a two-quadrant operation mode; the second DC-DC converter unit includes a dual active bridge and a second H-bridge.

[0009] The third DC-DC converter module includes several parallel third DC-DC converter units, which are used to provide output in single-quadrant operation mode;

[0010] The input terminals of the first DC-DC converter, the second DC-DC converter, and the third DC-DC converter are connected in parallel to the DC bus at the output terminal of the AC-DC converter.

[0011] As an improvement to the above solution, the modular multi-port power supply also includes a controller;

[0012] The controller is configured to acquire power supply operating parameters, and optimize the power supply control parameters using a multi-objective evolutionary algorithm with the optimization objectives of minimizing DC bus voltage error, minimizing output current deviation, and minimizing system power deviation, to obtain an optimized power allocation coefficient; and adjust the output power of the corresponding output ports of the first DC-DC converter module, the second DC-DC converter module, and the third DC-DC converter module according to the optimized power allocation coefficient.

[0013] As an improvement to the above scheme, the power supply control parameters include voltage loop control parameters, current loop control parameters, and power distribution coefficient;

[0014] The optimization objectives are to minimize the DC bus voltage error, the output current deviation, and the system power deviation. A multi-objective evolutionary algorithm is used to optimize the power supply control parameters, including:

[0015] The objective function is constructed with the optimization objectives of minimizing DC bus voltage error, minimizing output current deviation, and minimizing system power deviation.

[0016] Based on the objective function, a decomposition-based multi-objective evolutionary algorithm is used to optimize the voltage loop control parameters, current loop control parameters, and power allocation coefficients of the power supply, resulting in optimized voltage loop control parameters, current loop control parameters, and power allocation coefficients.

[0017] As an improvement to the above scheme, the optimization of power control parameters using a multi-objective evolutionary algorithm includes:

[0018] Constructing the aggregation function: The Chebyshev aggregation method is adopted to determine the aggregation function based on the optimization objectives of minimizing DC bus voltage error, minimizing output current deviation, and minimizing system power deviation. Each optimization objective in the aggregation function is assigned a corresponding weight.

[0019] Initialization: Initialize the weights and neighborhoods of each optimization objective, and initialize the population and ideal point composed of the power control parameters;

[0020] Update the ideal point: For each optimization objective, generate a new solution by performing crossover and mutation in the neighborhood; calculate the fitness based on the new solution, and update the ideal point according to the fitness.

[0021] Update neighborhood solutions: For each weight's neighborhood, update the solutions in the neighborhood according to the new solution and the value of the aggregation function corresponding to each solution in the neighborhood;

[0022] Iterative optimization: Repeat the steps of updating the ideal point and updating the neighborhood solution until the preset termination condition is met, then stop the iteration and output the solution corresponding to the current ideal point as the optimal solution.

[0023] As an improvement to the above scheme, the weight of the optimization objective is set according to the load changes of each output port.

[0024] As an improvement to the above scheme, the dual active bridge of the first DC-DC converter unit is composed of a first active bridge, a first transformer, and a second active bridge.

[0025] The DC input terminal of the first active bridge is connected to the DC bus of the output terminal of the AC-DC converter module; both the first and second active bridges are composed of four active switches connected in a full-bridge configuration; the AC side of the first active bridge and the AC side of the second active bridge are coupled together through the first transformer; the DC output terminal of the second active bridge is connected to the DC input terminal of the first H-bridge after being filtered by a first intermediate circuit composed of an inductor and a capacitor; the output terminal of the first H-bridge is connected to the output terminal of the first DC-DC converter module after being filtered by an inductor.

[0026] The first H-bridge is composed of four controllable switching devices connected in an H-bridge configuration. It is used to form a path by controlling the controllable switching devices under forward and reverse current conditions, so as to support the four-quadrant operation capability of the first DC-DC converter module.

[0027] As an improvement to the above scheme, the dual active bridge of the second DC-DC converter unit is composed of a third active bridge, a second transformer, and a fourth active bridge.

[0028] The DC input terminal of the third active bridge is connected to the DC bus of the output terminal of the AC-DC converter module; both the third and fourth active bridges are composed of four active switches connected in a full-bridge configuration; the AC side of the third active bridge and the AC side of the fourth active bridge are coupled together through the second transformer; the DC output terminal of the fourth active bridge is connected to the DC input terminal of the second H bridge after being filtered by a second intermediate circuit composed of an inductor and a capacitor; the output terminal of the second H bridge is connected to the output terminal of the second DC-DC converter module after being filtered by an inductor.

[0029] In the second H-bridge, the positive input terminal is connected to the positive output terminal through a first controllable switch device, and the positive input terminal is also connected to the negative output terminal through a first diode, with the anode of the first diode connected to the negative output terminal; the negative input terminal is connected to the negative output terminal through a second controllable switch device, and the negative input terminal is also connected to the positive output terminal through a second diode, with the anode of the second diode connected to the negative input terminal.

[0030] As an improvement to the above scheme, the third DC-DC converter module includes a phase-shifting full-bridge, a third transformer, and a synchronous rectifier circuit;

[0031] The DC input terminal of the phase-shifting full bridge is connected to the DC bus of the output terminal of the AC-DC conversion module; the phase-shifting full bridge is composed of four active switches connected in a full bridge configuration; the AC side of the phase-shifting full bridge is coupled to the AC side of the synchronous rectifier circuit through the third transformer.

[0032] In the synchronous rectification circuit, the two ends of the secondary winding of the third transformer are connected to a first point after passing through several parallel power field-effect transistors. The first point is connected to the output terminal of the third DC-DC converter module after passing through a filter circuit composed of an inductor and a capacitor. The middle end of the secondary winding of the third transformer is connected to the negative output terminal of the third DC-DC converter module.

[0033] As an improvement to the above solution, the AC-DC conversion module consists of a three-phase pulse width modulation rectifier circuit and a filter circuit;

[0034] The AC-DC conversion module adopts independent voltage loop control. By comparing the actual voltage at the output terminal of the AC-DC conversion module with the preset reference voltage, the modulation ratio of the three-phase pulse width modulation rectifier circuit is controlled to adjust the output voltage of the AC-DC conversion module.

[0035] This application also provides a control method for a single-input multiple-output modular multi-port power supply, applied to the aforementioned single-input multiple-output modular multi-port power supply, the control method comprising:

[0036] Obtain the DC bus voltage of the power supply, the output current and output power of each output port;

[0037] Based on the DC bus voltage, the output current and the output power, with the optimization objectives of minimizing the DC bus voltage error, the output current deviation and the system power deviation, a multi-objective evolutionary algorithm is used to optimize the power supply control parameters, and the optimized voltage loop control parameters, current loop control parameters and power allocation coefficient are obtained.

[0038] The output voltage of the AC-DC conversion module is controlled according to the voltage loop control parameters.

[0039] The output current of the first DC-DC converter module, the second DC-DC converter module, and the third DC-DC converter module is controlled according to the current loop control parameters.

[0040] The output power of the first DC-DC converter module, the second DC-DC converter module, and the third DC-DC converter module is controlled according to the power allocation coefficient.

[0041] Compared with existing technologies, the advantages of the single-input multiple-output modular multi-port power supply and its control method provided in this application are as follows:

[0042] By setting up an AC-DC conversion module, a first DC conversion module including several parallel first DC conversion units, a second DC conversion module including several parallel second DC conversion units, and a third DC conversion module including several parallel third DC conversion units, and with the input terminals of the first, second, and third DC conversion modules connected in parallel to the DC bus of the AC-DC conversion module output terminal, it can provide outputs in multiple operating modes such as four-quadrant, two-quadrant, and single-quadrant with a wide voltage adjustment range. It can flexibly configure energy unidirectional and bidirectional modules with different output voltages according to usage requirements, effectively improving the flexibility, scalability, and stability of the multi-port modular power supply.

[0043] By employing a decomposition-based multi-objective evolutionary algorithm, with the optimization objectives of minimizing DC bus voltage error, output current deviation, and system power deviation, the voltage loop control parameters, current loop control parameters, and power allocation coefficient are synergistically optimized. This improves the accuracy of power supply control, ensures the stability of system voltage and port current, and achieves dynamic balance of system power, making it suitable for complex power supply system control. Attached Figure Description

[0044] Figure 1 This is a circuit topology diagram of a modular multiport power supply with single input and multiple outputs provided in an embodiment of this application;

[0045] Figure 2This is a control schematic diagram of an AC-DC conversion module in a modular multi-port power supply with single input and multiple outputs provided in an embodiment of this application;

[0046] Figure 3 This is a control schematic diagram of a DC-DC converter module in a modular multi-port power supply with single input and multiple outputs provided in an embodiment of this application;

[0047] Figure 4 This is a flowchart illustrating a control method for a modular multi-port power supply with single input and multiple outputs provided in an embodiment of this application. Detailed Implementation

[0048] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0049] To address the shortcomings of existing multi-port power supplies in terms of flexibility, scalability, and stability in terms of topology and device compatibility, embodiments of this application provide a modular multi-port power supply with single-input multiple-output, comprising:

[0050] An AC-DC converter module is used to convert three-phase AC input into DC output;

[0051] The first DC-DC converter module includes several parallel first DC-DC converter units for providing output in a four-quadrant operating mode; the first DC-DC converter unit includes a dual active bridge and a first H-bridge.

[0052] The second DC-DC converter module includes several parallel second DC-DC converter units for providing output in a two-quadrant operation mode; the second DC-DC converter unit includes a dual active bridge and a second H-bridge.

[0053] The third DC-DC converter module includes several parallel third DC-DC converter units, which are used to provide output in single-quadrant operation mode;

[0054] The input terminals of the first DC-DC converter, the second DC-DC converter, and the third DC-DC converter are connected in parallel to the DC bus at the output terminal of the AC-DC converter.

[0055] Specifically, the modular multi-port power supply can be divided into an AC-DC (Alternating Current to Direct Current) section and a DC-DC (Direct Current to Direct Current) section. The DC-DC section shares a common DC bus with the AC-DC output. The AC-DC section, i.e., the AC-DC conversion module, uses PWM (Pulse Width Modulation) rectification to improve the power factor and provide a bidirectional energy flow feedback channel to the grid. The DC-DC section, i.e., the DC-DC conversion module, includes a first DC-DC conversion module, a second DC-DC conversion module, and a third DC-DC conversion module. The DC-DC section employs topologies such as dual active bridges + H-bridges and synchronous rectification, providing ports for unidirectional or bidirectional energy flow selection, and offering single-quadrant, two-quadrant, and four-quadrant operation with a wide voltage regulation range. Furthermore, the DC-DC section can be flexibly configured with power modules of different output voltages according to usage requirements.

[0056] In this context, single-quadrant refers to providing both positive voltage and positive current. Two-quadrant refers to providing both positive and negative voltage and positive current. Four-quadrant refers to providing both positive and negative voltage and both positive and negative current. This application specifically applies to superconducting magnet power systems, providing selection of different quadrant operating conditions based on the characteristics of different superconducting loads and required testing conditions. For example, some test loads have relatively small energy storage, such as superconducting cable testing, where energy can be discharged through a loop; in this case, single-quadrant operation mode power output is sufficient for testing requirements. Some superconducting loads have large energy, requiring bidirectional energy feedback after testing to return the energy stored during load operation to the grid; in this case, two-quadrant operation mode power output is used to improve energy utilization. Some superconducting load testing processes are more complex, requiring four-quadrant operation with both positive and negative voltage and current; in this case, four-quadrant operation mode power output is used.

[0057] Please see Figure 1 , Figure 1 This is a circuit topology diagram of a modular multi-port power supply with single input and multiple outputs provided in this application embodiment. The power supply receives a three-phase AC input, which is then rectified by a three-phase PWM converter and filtered by an LC filter to output a stable DC voltage. The outputs to different load ports are achieved through parallel-connected first, second, and third DC-DC converter modules. The first DC-DC converter module corresponds to the four-quadrant operation mode and load 1, and consists of at least two parallel first DC-DC converter units; the second DC-DC converter module corresponds to the two-quadrant operation mode and load 2, and consists of at least two parallel second DC-DC converter units; the third DC-DC converter module corresponds to the single-quadrant operation mode and load 3, and consists of at least two parallel third DC-DC converter units. This application embodiment uses a dual active bridge in conjunction with an H-bridge for voltage regulation to achieve wide voltage range adjustment for both two-quadrant and four-quadrant operation; for loads without bidirectional operation requirements, a phase-shifted full-bridge synchronous rectification module is used to achieve single-quadrant operation.

[0058] It should be noted that, since the power supply in this embodiment is a modular power supply, the number of parallel connections of the first DC-DC converter unit, the second DC-DC converter unit, and the third DC-DC converter unit can be specifically set according to the load current requirements.

[0059] As one optional embodiment, the AC-DC conversion module consists of a three-phase pulse width modulation rectifier circuit and a filter circuit;

[0060] The AC-DC conversion module adopts independent voltage loop control. By comparing the actual voltage at the output terminal of the AC-DC conversion module with the preset reference voltage, the modulation ratio of the three-phase pulse width modulation rectifier circuit is controlled to adjust the output voltage of the AC-DC conversion module.

[0061] Specifically, the AC-DC converter module uses three-phase PWM rectification and LC filtering. The three-phase pulse width modulation rectifier circuit includes six power switching transistors with anti-parallel diodes. After the three-phase input of the AC grid passes through the three-phase pulse width modulation rectifier circuit, it is filtered by a filter circuit composed of inductors and capacitors. The DC output voltage Vdc is obtained from the two ends of the capacitor, which serves as the input of the DC-DC converter module.

[0062] Please see Figure 2 In this embodiment, the output voltage of the AC-DC module is controlled by an independent voltage loop. First, the actual DC output voltage Vdc of the AC-DC module is acquired. Then, it is compared with the DC output voltage Vdc by a preset reference voltage Vref. PI feedback is used to control the modulation ratio of each power switch, thereby stabilizing the DC output voltage Vdc on the rectifier side.

[0063] As one optional embodiment, the dual active bridge of the first DC-DC converter unit is composed of a first active bridge, a first transformer, and a second active bridge;

[0064] The DC input terminal of the first active bridge is connected to the DC bus of the output terminal of the AC-DC converter module; both the first and second active bridges are composed of four active switches connected in a full-bridge configuration; the AC side of the first active bridge and the AC side of the second active bridge are coupled together through the first transformer; the DC output terminal of the second active bridge is connected to the DC input terminal of the first H-bridge after being filtered by a first intermediate circuit composed of an inductor and a capacitor; the output terminal of the first H-bridge is connected to the output terminal of the first DC-DC converter module after being filtered by an inductor.

[0065] The first H-bridge is composed of four controllable switching devices connected in an H-bridge configuration. It is used to form a path by controlling the controllable switching devices under forward and reverse current conditions, so as to support the four-quadrant operation capability of the first DC-DC converter module.

[0066] Specifically, the first active bridge is connected to the primary winding of the first transformer via a series inductor and capacitor, and the secondary winding of the first transformer is connected to the second active bridge. The first transformer is a high-frequency transformer with a transformer ratio of N1:1, which can be set according to the voltage requirements of the load test to provide different levels of output voltage.

[0067] In this application, since the voltage of the superconducting load is extremely low during long-term steady-state operation, the high-frequency transformer turns ratio is required, and a large turns ratio is needed. In addition, the power supply efficiency is low under low voltage output of the dual active bridge, which also puts high demands on the transformer. Therefore, a single-stage H-bridge is connected to the dual active bridge to reduce the voltage regulation pressure of the high-frequency transformer and provide a wide range of voltage regulation.

[0068] The first active bridge converts DC to AC, and the second active bridge converts it back to DC to obtain a stepped-down DC voltage. Then, based on the voltage required by the load operating conditions, the H-bridge is used to chop and regulate the DC voltage output by the dual active bridges to obtain an output with a wide voltage regulation range.

[0069] The first H-bridge consists of two sets of half-bridges. Each half-bridge includes an upper bridge arm switch and a lower bridge arm switch. The four switches are arranged in a conventional H-bridge configuration to form the bridge arm structure. All four active switches in the first H-bridge are controllable switching devices, required to withstand and actively control both forward and reverse currents. They are typically implemented using fully controlled devices and driven to enable the bridge arm to actively switch on and off under any polarity. The output terminals of the bridge arm are connected to the module output after output filtering.

[0070] As one optional embodiment, the dual active bridge of the second DC-DC converter unit is composed of a third active bridge, a second transformer, and a fourth active bridge;

[0071] The DC input terminal of the third active bridge is connected to the DC bus of the output terminal of the AC-DC converter module; both the third and fourth active bridges are composed of four active switches connected in a full-bridge configuration; the AC side of the third active bridge and the AC side of the fourth active bridge are coupled together through the second transformer; the DC output terminal of the fourth active bridge is connected to the DC input terminal of the second H bridge after being filtered by a second intermediate circuit composed of an inductor and a capacitor; the output terminal of the second H bridge is connected to the output terminal of the second DC-DC converter module after being filtered by an inductor.

[0072] In the second H-bridge, the positive input terminal is connected to the positive output terminal through a first controllable switch device, and the positive input terminal is also connected to the negative output terminal through a first diode, with the anode of the first diode connected to the negative output terminal; the negative input terminal is connected to the negative output terminal through a second controllable switch device, and the negative input terminal is also connected to the positive output terminal through a second diode, with the anode of the second diode connected to the negative input terminal.

[0073] Specifically, the third active bridge is connected to the primary winding of the second transformer via a series inductor and capacitor, and the secondary winding of the second transformer is connected to the fourth active bridge. The second transformer is a high-frequency transformer with a transformer ratio of N2:1, which can be set according to the voltage requirements of the load test to provide different levels of output voltage.

[0074] The second H-bridge is a semi-controlled H-bridge structure, consisting of two sets of half-bridges. Each set includes an upper bridge arm switch and a lower bridge arm switch, constructed from power MOSFETs and diodes. The second H-bridge serves as a downstream chopper unit to achieve two-quadrant output. Through the combination of power MOSFETs and diodes, the diodes can handle the return or freewheeling path when reverse processing is required, improving operational stability and reliability while reducing control complexity. Furthermore, compared to the four-quadrant circuit of the first DC-DC converter module, the second H-bridge has lower controller complexity, lower component cost, and lower control power consumption compared to the fully controlled four-switch H-bridge.

[0075] As one optional embodiment, the third DC-DC converter module includes a phase-shifting full-bridge, a third transformer, and a synchronous rectifier circuit;

[0076] The DC input terminal of the phase-shifting full bridge is connected to the DC bus of the output terminal of the AC-DC conversion module; the phase-shifting full bridge is composed of four active switches connected in a full bridge configuration; the AC side of the phase-shifting full bridge is coupled to the AC side of the synchronous rectifier circuit through the third transformer.

[0077] In the synchronous rectification circuit, the two ends of the secondary winding of the third transformer are connected to a first point after passing through several parallel power field-effect transistors. The first point is connected to the output terminal of the third DC-DC converter module after passing through a filter circuit composed of an inductor and a capacitor. The middle end of the secondary winding of the third transformer is connected to the negative output terminal of the third DC-DC converter module.

[0078] Specifically, the phase-shifted full-bridge converter consists of four active switches connected in a full-bridge configuration. The midpoints of the two arms of the phase-shifted full-bridge are connected to the two ends of the primary winding of the third transformer, respectively. The output of the phase-shifted full-bridge generates a differential drive signal for the primary winding of the third transformer. The third transformer is a high-frequency transformer with a transformer ratio of N3:1. The third transformer has multiple sets of secondary windings, with both ends of the secondary windings connected to the input terminals of the synchronous rectification circuit. The synchronous rectification circuit is an active bridge composed of power MOSFETs, divided into upper and lower groups, each group consisting of several power MOSFETs with parallel diodes connected in parallel. The output of the synchronous rectification circuit is further filtered and then fed into the output of the third DC-DC converter module to provide single-quadrant operation. When the load demand is low, this power output port can be selected to reduce control complexity and improve operating efficiency.

[0079] Further, please refer to Figure 3 The output current of the DC-DC module adopts independent current loop feedback control. By comparing the set reference current Iref with the actual output current Io, the output voltage of the DC-DC module is adjusted through PI feedback control, thereby stabilizing the load output current Io.

[0080] As one optional embodiment, the modular multiport power supply also includes a controller;

[0081] The controller is configured to acquire power supply operating parameters, and optimize the power supply control parameters using a multi-objective evolutionary algorithm with the optimization objectives of minimizing DC bus voltage error, minimizing output current deviation, and minimizing system power deviation, to obtain an optimized power allocation coefficient; and adjust the output power of the corresponding output ports of the first DC-DC converter module, the second DC-DC converter module, and the third DC-DC converter module according to the optimized power allocation coefficient.

[0082] Specifically, the power supply system in this embodiment employs a decomposition-based multi-objective evolutionary algorithm. This algorithm transforms the multi-objective problem requiring optimization into multiple single-objective sub-problems and coordinates their control optimization. The objective function is established with the minimum DC bus voltage error, minimum output current deviation, and minimum system power deviation as comprehensive optimization indicators. The DC bus voltage, output current at each port, and power are monitored in real time. By adjusting the weight vector in the optimization algorithm, the algorithm quickly responds to changes in objective priority. Power control is implemented based on the optimized power control parameters to adapt to sudden load changes and operating mode switching, meeting the dynamic needs of different loads.

[0083] Furthermore, the function corresponding to the optimization objective of minimizing the DC bus voltage error is: ,in, The DC output voltage of the AC-DC converter module. This is the preset reference voltage. By adjusting the voltage loop control parameters, i.e., the voltage loop PI parameters, the output voltage error is minimized, thereby ensuring the stability of the AC-DC rectifier side voltage.

[0084] Furthermore, the function corresponding to the optimization objective of minimizing the output current deviation is: ,in, This is the sum of the deviations of the output current at each port, used to represent the stability of the output current at each port. By adjusting the current loop control parameters, i.e., the current loop PI parameters, current ripple and tracking error are suppressed, minimizing the sum of the current deviations at each output port, thereby controlling the stability of the output current.

[0085] Furthermore, the function corresponding to the optimization objective of minimizing the system power deviation is: ,in, The preset reference output power, This refers to the actual output power. The actual output power is as follows:

[0086]

[0087] in, and Let represent the output power and power allocation coefficient of the i-th port, respectively. By adjusting the power allocation coefficient of each port, the system can adapt to changes in load power and minimize the system power deviation.

[0088] As one optional embodiment, the power supply control parameters include voltage loop control parameters, current loop control parameters, and power allocation coefficient;

[0089] The optimization objectives are to minimize the DC bus voltage error, the output current deviation, and the system power deviation. A multi-objective evolutionary algorithm is used to optimize the power supply control parameters, including:

[0090] The objective function is constructed with the optimization objectives of minimizing DC bus voltage error, minimizing output current deviation, and minimizing system power deviation.

[0091] Based on the objective function, a decomposition-based multi-objective evolutionary algorithm is used to optimize the voltage loop control parameters, current loop control parameters, and power allocation coefficients of the power supply, resulting in optimized voltage loop control parameters, current loop control parameters, and power allocation coefficients.

[0092] Specifically, the weights corresponding to the three optimization objectives—minimizing DC bus voltage error, minimizing output current deviation, and minimizing system power deviation—are set as follows: , , Construct the objective function for multi-objective optimization, as shown in the following formula:

[0093]

[0094] in, The overall optimization objective is to ensure that voltage, current, and power deviations remain within certain ranges. If these ranges are exceeded, operation ceases to guarantee the safety of the power system.

[0095] Using the objective function as the fitness function, and the voltage loop control parameters, current loop control parameters, and power allocation coefficients as optimization variables, a decomposition-based multi-objective evolutionary algorithm is used for iterative optimization to obtain the optimized voltage loop control parameters, current loop control parameters, and power allocation coefficients.

[0096] This application embodiment aims to stabilize the output voltage and current of the AC-DC section and each port by using a multi-objective optimization algorithm to optimize and adjust the PI parameters of the voltage and current loops, thereby stabilizing the output voltage and current. Simultaneously, considering load characteristics and system operating mode, the output power of each port is controlled and adjusted. By adjusting the power distribution coefficient between ports, the port power is adaptively adjusted within a certain range, ensuring coordinated and stable operation of the power supply system.

[0097] As one optional embodiment, the optimization of power control parameters using a multi-objective evolutionary algorithm includes:

[0098] Constructing the aggregation function: The Chebyshev aggregation method is adopted to determine the aggregation function based on the optimization objectives of minimizing DC bus voltage error, minimizing output current deviation, and minimizing system power deviation. Each optimization objective in the aggregation function is assigned a corresponding weight.

[0099] Initialization: Initialize the weights and neighborhoods of each optimization objective, and initialize the population and ideal point composed of the power control parameters;

[0100] Update the ideal point: For each optimization objective, generate a new solution by performing crossover and mutation in the neighborhood; calculate the fitness based on the new solution, and update the ideal point according to the fitness.

[0101] Update neighborhood solutions: For each weight's neighborhood, update the solutions in the neighborhood according to the new solution and the value of the aggregation function corresponding to each solution in the neighborhood;

[0102] Iterative optimization: Repeat the steps of updating the ideal point and updating the neighborhood solution until the preset termination condition is met, then stop the iteration and output the solution corresponding to the current ideal point as the optimal solution.

[0103] Specifically, the Chebyshev method is adopted, and the priority of objectives is flexibly allocated by optimizing the weights of the objectives, thus constructing the aggregation function corresponding to the Chebyshev method. The formula is as follows:

[0104]

[0105] The weight of the optimization objective is: ; Let x be the ideal point, representing the theoretical minimum value of each optimization objective. The aggregation function aggregates multiple objectives into a single scalar value. The ultimate goal of the multi-objective evolutionary algorithm is to find the optimal solution x.

[0106] Furthermore, the specific steps of the multi-objective evolutionary algorithm are as follows:

[0107] First, initialize the parameters: generate N sets of weights using a uniform distribution, such as... Calculate the Euclidean distance between the weights and define a neighborhood set for each weight for each optimization objective. Randomly generate N combinations of power supply control parameters as the initial population. Each combination of power supply control parameters is denoted as x, which includes voltage loop control parameters, current loop control parameters, and power allocation coefficients. Calculate the ideal point of the optimization objective based on the initialized parameters. Thus, the initial ideal point is obtained.

[0108] Furthermore, parameter updates and iterations are performed. For each iteration, two solutions are randomly selected from the neighborhood for each optimization objective, and then new solutions are generated through crossover and mutation. The new solutions are then subjected to boundary checks and corrections based on the constraints, and finally, the function values ​​of each optimization objective corresponding to the new solutions are calculated. , , The fitness value corresponding to the new solution is obtained. Based on the calculated optimization objective... , , Determine if the candidate ideal point corresponding to the new solution is smaller than the current ideal point. If so, update the candidate ideal point to the current ideal point. Then update For each solution in the neighborhood, calculate its corresponding aggregation function value, and at the same time calculate the aggregation function value corresponding to the new solution. By comparing the aggregation function values ​​of the new solution with those of the neighborhood solutions, update the neighborhood solutions with the new solution.

[0109] Finally, based on the set maximum number of iterations or the convergence value of the objective function, the optimization algorithm terminates when the termination condition is met, outputs the final solution, and obtains the optimized power control parameters.

[0110] Optionally, the weights of the optimization objectives are set according to the load changes of each output port. A set of weight coefficient values ​​can be initially defined based on load characteristics and control conditions, and then the weight coefficients can be adaptively or manually adjusted based on the operation process and load characteristics. As a weighting coefficient, it represents the relative importance of different objectives. For example, when high load fluctuations are detected, the weight is increased. When output current requirements are stringent, increase the weighting. When power balance is sensitive, increase the weight. .

[0111] This application's embodiments utilize a decomposition-based multi-objective algorithm to perform local updates using neighbor information, avoiding the global non-dominated sorting and congestion calculations found in traditional multi-objective optimization algorithms. Furthermore, the search direction can be guided by designing the weights of the optimization objectives; the distribution of these weights determines the distribution of the solution set, resulting in diverse controllability. Through this decomposition-based multi-objective evolutionary algorithm, the three control objectives—rectifier-side voltage stability, output current stability, and port power balance—are decomposed into co-optimized sub-problems, ultimately yielding a balanced set of PID parameters and power allocation and adjustment gain coefficients. This application ensures both system voltage and port current stability while achieving dynamic system power balance, making it suitable for the multi-objective optimization needs of complex power supply systems.

[0112] Accordingly, this application also provides a control method for a single-input multiple-output modular multiport power supply, applied to the aforementioned single-input multiple-output modular multiport power supply, such as... Figure 4 As shown, the control method includes:

[0113] S1: Obtain the DC bus voltage of the power supply, the output current and output power of each output port;

[0114] S2: Based on the DC bus voltage, the output current and the output power, with the optimization objectives of minimizing the DC bus voltage error, the output current deviation and the system power deviation, a multi-objective evolutionary algorithm is used to optimize the power supply control parameters to obtain the optimized voltage loop control parameters, current loop control parameters and power allocation coefficient.

[0115] S3: Control the output voltage of the AC-DC converter module according to the voltage loop control parameters;

[0116] S4: Control the output current of the first DC-DC converter module, the second DC-DC converter module and the third DC-DC converter module according to the current loop control parameters;

[0117] S5: Control the output power of the first DC-DC converter module, the second DC-DC converter module and the third DC-DC converter module according to the power allocation coefficient.

[0118] Furthermore, the optimization of power control parameters using a multi-objective evolutionary algorithm includes:

[0119] Constructing the aggregation function: The Chebyshev aggregation method is adopted to determine the aggregation function based on the optimization objectives of minimizing DC bus voltage error, minimizing output current deviation, and minimizing system power deviation. Each optimization objective in the aggregation function is assigned a corresponding weight.

[0120] Initialization: Initialize the weights and neighborhoods of each optimization objective, and initialize the population and ideal point composed of the power control parameters;

[0121] Update the ideal point: For each optimization objective, generate a new solution by performing crossover and mutation in the neighborhood; calculate the fitness based on the new solution, and update the ideal point according to the fitness.

[0122] Update neighborhood solutions: For each weight's neighborhood, update the solutions in the neighborhood according to the new solution and the value of the aggregation function corresponding to each solution in the neighborhood;

[0123] Iterative optimization: Repeat the steps of updating the ideal point and updating the neighborhood solution until the preset termination condition is met, then stop the iteration and output the solution corresponding to the current ideal point as the optimal solution.

[0124] Furthermore, the weights of the optimization objectives are set according to the load changes of each output port.

[0125] This application provides a modular multi-port power supply with single-input multiple-output and its control method. The advantages are as follows: By setting up an AC-DC conversion module, a first DC-DC conversion module including several parallel first DC-DC conversion units, a second DC-DC conversion module including several parallel second DC-DC conversion units, and a third DC-DC conversion module including several parallel third DC-DC conversion units, with the input terminals of the first, second, and third DC-DC conversion modules connected in parallel to the DC bus of the AC-DC conversion module's output terminal, it can provide outputs in multiple operating modes such as four-quadrant, two-quadrant, and single-quadrant modes with a wide voltage regulation range. It allows for flexible configuration of unidirectional and bidirectional energy modules with different output voltages according to usage requirements, effectively improving the flexibility, scalability, and stability of the multi-port modular power supply. By employing a decomposition-based multi-objective evolutionary algorithm, with the optimization objectives of minimizing DC bus voltage error, output current deviation, and system power deviation, the voltage loop control parameters, current loop control parameters, and power allocation coefficients are synergistically optimized, improving the accuracy of power supply control, ensuring the stability of system voltage and port current, and simultaneously achieving dynamic system power balance, making it suitable for complex power supply system control.

[0126] The above description is the preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications are also considered to be within the scope of protection of this application.

Claims

1. A modular multi-port power supply with single-input multiple-output, characterized in that, include: An AC-DC converter module is used to convert three-phase AC input into DC output; The first DC-DC converter module includes several parallel first DC-DC converter units for providing output in a four-quadrant operating mode; the first DC-DC converter unit includes a dual active bridge and a first H-bridge. The second DC-DC converter module includes several parallel second DC-DC converter units for providing output in a two-quadrant operation mode; the second DC-DC converter unit includes a dual active bridge and a second H-bridge. The third DC-DC converter module includes several parallel third DC-DC converter units, which are used to provide output in single-quadrant operation mode; The input terminals of the first DC-DC converter, the second DC-DC converter, and the third DC-DC converter are connected in parallel to the DC bus of the output terminal of the AC-DC converter. The modular multi-port power supply also includes a controller; The controller is configured to acquire power supply operating parameters, and optimize the power supply control parameters using a multi-objective evolutionary algorithm with the optimization objectives of minimizing DC bus voltage error, minimizing output current deviation, and minimizing system power deviation, to obtain an optimized power allocation coefficient; and adjust the output power of the corresponding output ports of the first DC-DC converter module, the second DC-DC converter module, and the third DC-DC converter module according to the optimized power allocation coefficient.

2. The modular multi-port power supply with single input and multiple outputs as described in claim 1, characterized in that, The power supply control parameters include voltage loop control parameters, current loop control parameters, and power distribution coefficients. The optimization objectives are to minimize the DC bus voltage error, the output current deviation, and the system power deviation. A multi-objective evolutionary algorithm is used to optimize the power supply control parameters, including: The objective function is constructed with the optimization objectives of minimizing DC bus voltage error, minimizing output current deviation, and minimizing system power deviation. Based on the objective function, a decomposition-based multi-objective evolutionary algorithm is used to optimize the voltage loop control parameters, current loop control parameters, and power allocation coefficients of the power supply, resulting in optimized voltage loop control parameters, current loop control parameters, and power allocation coefficients.

3. The modular multi-port power supply with single input and multiple outputs as described in claim 1, characterized in that, The optimization of power control parameters using a multi-objective evolutionary algorithm includes: Constructing the aggregation function: The Chebyshev aggregation method is adopted to determine the aggregation function based on the optimization objectives of minimizing DC bus voltage error, minimizing output current deviation, and minimizing system power deviation. Each optimization objective in the aggregation function is assigned a corresponding weight. Initialization: Initialize the weights and neighborhoods of each optimization objective, and initialize the population and ideal point composed of the power control parameters; Update the ideal point: For each optimization objective, generate a new solution by performing crossover and mutation in the neighborhood; calculate the fitness based on the new solution, and update the ideal point according to the fitness. Update neighborhood solutions: For each weight's neighborhood, update the solutions in the neighborhood according to the new solution and the value of the aggregation function corresponding to each solution in the neighborhood; Iterative optimization: Repeat the steps of updating the ideal point and updating the neighborhood solution until the preset termination condition is met, then stop the iteration and output the solution corresponding to the current ideal point as the optimal solution.

4. The modular multi-port power supply with single input and multiple outputs as described in claim 3, characterized in that, The weights of the optimization objectives are set according to the load changes of each output port.

5. The modular multi-port power supply with single input and multiple outputs as described in claim 1, characterized in that, The dual active bridge of the first DC-DC converter unit consists of a first active bridge, a first transformer, and a second active bridge; The DC input terminal of the first active bridge is connected to the DC bus of the output terminal of the AC-DC converter module; both the first and second active bridges are composed of four active switches connected in a full-bridge configuration; the AC side of the first active bridge and the AC side of the second active bridge are coupled together through the first transformer; the DC output terminal of the second active bridge is connected to the DC input terminal of the first H-bridge after being filtered by a first intermediate circuit composed of an inductor and a capacitor; the output terminal of the first H-bridge is connected to the output terminal of the first DC-DC converter module after being filtered by an inductor. The first H-bridge is composed of four controllable switching devices connected in an H-bridge configuration. It is used to form a path by controlling the controllable switching devices under forward and reverse current conditions, so as to support the four-quadrant operation capability of the first DC-DC converter module.

6. The modular multi-port power supply with single input and multiple outputs as described in claim 1, characterized in that, The dual active bridge of the second DC-DC converter unit consists of a third active bridge, a second transformer, and a fourth active bridge; The DC input terminal of the third active bridge is connected to the DC bus of the output terminal of the AC-DC converter module; both the third and fourth active bridges are composed of four active switches connected in a full-bridge configuration; the AC side of the third active bridge and the AC side of the fourth active bridge are coupled together through the second transformer; the DC output terminal of the fourth active bridge is connected to the DC input terminal of the second H bridge after being filtered by a second intermediate circuit composed of an inductor and a capacitor; the output terminal of the second H bridge is connected to the output terminal of the second DC-DC converter module after being filtered by an inductor. In the second H-bridge, the positive input terminal is connected to the positive output terminal through a first controllable switch device, and the positive input terminal is also connected to the negative output terminal through a first diode, with the anode of the first diode connected to the negative output terminal; the negative input terminal is connected to the negative output terminal through a second controllable switch device, and the negative input terminal is also connected to the positive output terminal through a second diode, with the anode of the second diode connected to the negative input terminal.

7. The modular multi-port power supply with single input and multiple outputs as described in claim 1, characterized in that, The third DC-DC converter module includes a phase-shifting full-bridge converter, a third transformer, and a synchronous rectifier circuit. The DC input terminal of the phase-shifting full bridge is connected to the DC bus of the output terminal of the AC-DC conversion module; the phase-shifting full bridge is composed of four active switches connected in a full bridge configuration; the AC side of the phase-shifting full bridge is coupled to the AC side of the synchronous rectifier circuit through the third transformer. In the synchronous rectification circuit, the two ends of the secondary winding of the third transformer are connected to a first point after passing through several parallel power field-effect transistors. The first point is connected to the output terminal of the third DC-DC converter module after passing through a filter circuit composed of an inductor and a capacitor. The middle end of the secondary winding of the third transformer is connected to the negative output terminal of the third DC-DC converter module.

8. The modular multi-port power supply with single input and multiple outputs as described in claim 1, characterized in that, The AC-DC conversion module consists of a three-phase pulse width modulation rectifier circuit and a filter circuit; The AC-DC conversion module adopts independent voltage loop control. By comparing the actual voltage at the output terminal of the AC-DC conversion module with the preset reference voltage, the modulation ratio of the three-phase pulse width modulation rectifier circuit is controlled to adjust the output voltage of the AC-DC conversion module.

9. A control method for a modular multi-port power supply with single-input multiple-output, characterized in that, The control method, applied to a modular multi-port power supply with single-input multiple-output as described in any one of claims 1 to 8, comprises: Obtain the DC bus voltage of the power supply, the output current and output power of each output port; Based on the DC bus voltage, the output current and the output power, with the optimization objectives of minimizing the DC bus voltage error, the output current deviation and the system power deviation, a multi-objective evolutionary algorithm is used to optimize the power supply control parameters, and the optimized voltage loop control parameters, current loop control parameters and power allocation coefficient are obtained. The output voltage of the AC-DC conversion module is controlled according to the voltage loop control parameters. The output current of the first DC-DC converter module, the second DC-DC converter module, and the third DC-DC converter module is controlled according to the current loop control parameters. The output power of the first DC-DC converter module, the second DC-DC converter module, and the third DC-DC converter module is controlled according to the power allocation coefficient.

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