Cooperative control method and system of multi-module converter

Abstract

The invention provides a cooperative control method and system for a multi-module converter, and relates to the technical field of converter control, and the method comprises the steps: obtaining a plurality of real-time operation states and a plurality of real-time loads of a plurality of converter modules; calling a user load demand, and determining a working mode of the converter; generating an initial control strategy in combination with the plurality of real-time operation states; according to the cooperative control target, optimizing the initial control strategy to obtain a control optimization strategy; and constructing a standard plug-in frame, and carrying out modular management on the converter. The technical problem that the cooperative control efficiency of the converter is low due to the fact that the power combination mode of the converter is fixed and is difficult to flexibly adjust according to actual requirements is solved, the working mode of the converter is adjusted in real time through the real-time loads, the operation states and the user load requirements of the multiple modules, and the cooperative control efficiency of the converter is improved. More accurate load distribution and power scheduling are realized; and the cooperative control efficiency of the converter is improved.

Description

Technical Field

[0001] This application relates to the technical field of converter control, and particularly to a cooperative control method and system for multi-module converters. Background Art

[0002] In existing power electronic systems, as one of the core components, converters are widely used in fields such as variable frequency speed regulation, new energy power generation, and energy storage systems. Currently, most converters on the market are high-power, lacking a modular plug-in strategy for low-power energy storage converters. Low-power energy storage converters usually need to face complex power load requirements and changing environmental conditions, so they are required to have efficient power conversion, stable grid connection capabilities, and flexible load regulation capabilities. The power combination method of traditional converter systems is relatively fixed, and the power output and working mode of modules often cannot be dynamically adjusted in real time according to actual load requirements and environmental changes, resulting in low cooperative control efficiency of multi-module converters under some load conditions and unable to achieve optimal utilization of energy. Especially in scenarios with large load fluctuations or rapid demand changes, the working mode cannot be flexibly adjusted, leading to uneven power distribution, overload of some modules, or power waste.

[0003] In summary, there is a technical problem in the prior art that due to the relatively fixed power combination method of converters, it is difficult to flexibly adjust according to actual needs, resulting in low cooperative control efficiency of converters. Summary of the Invention

[0004] The purpose of this application is to provide a cooperative control method and system for multi-module converters to solve the technical problem in the prior art that due to the relatively fixed power combination method of converters, it is difficult to flexibly adjust according to actual needs, resulting in low cooperative control efficiency of converters.

[0005] In view of the above problems, this application provides a cooperative control method and system for multi-module converters.

[0006] In the first aspect, this application provides a cooperative control method for multi-module converters. The cooperative control method for multi-module converters is implemented through a cooperative control system for multi-module converters. Among them, the cooperative control method for multi-module converters includes: obtaining multiple real-time operating states and multiple real-time loads of multiple converter modules; calling the user load demand, and determining the converter working mode based on the multiple real-time loads; generating an initial control strategy according to the converter working mode and in combination with the multiple real-time operating states; optimizing the initial control strategy according to the cooperative control target to obtain a control optimization strategy; and constructing a standard plug-in frame based on the control optimization strategy to perform modular management on the converter.

[0007] Optionally, the standard plug-in frame includes slots, a bus power supply, a control module, a lightning protection module, a disconnector, a power meter contactor, a plurality of converter modules, and a shunt.

[0008] Optionally, according to the user load demand, the maximum load power, the average load power, and the output voltage range are extracted; the plurality of rated powers and the plurality of voltage ranges of the plurality of converter modules are obtained; the number of converters is determined according to the maximum load power, the average load power, and the plurality of rated powers; according to the output voltage range and the plurality of voltage ranges, in combination with the number of converters, the operating mode of the converters is determined, where the operating mode of the converters includes a parallel operating mode, a series operating mode, and a hybrid operating mode.

[0009] Optionally, the average value of the plurality of rated powers is calculated to obtain the rated average power; according to the maximum load power and the rated average power, the first number of converters is calculated, and at the same time, according to the average load power and the rated average power, the second number of converters is calculated; a load fluctuation sequence is obtained from the central control unit, and a load factor is calculated; if the load factor is greater than or equal to a preset threshold, the first number of converters is used as the number of converters; if the load factor is less than the preset threshold, the second number of converters is used as the number of converters.

[0010] Optionally, step a: Obtain a first real-time operating state from the plurality of real-time operating states and upload it to the central control unit for judgment through a communication interface; step b: If the first real-time operating state does not meet the preset state, remove the first converter module corresponding to the first real-time operating state; for the plurality of real-time operating states, repeat steps a to b to obtain a plurality of preferred converter modules that all meet the preset state; obtain external power grid information from the central control unit; according to the converter operating mode, the plurality of preferred converter modules, in combination with the external power grid information, generate the initial control strategy.

[0011] Optionally, the external power grid information includes grid voltage fluctuation, grid load fluctuation, and grid frequency fluctuation.

[0012] Optionally, according to the maximization of load adaptation and power efficiency maximization of the collaborative control target, an objective function is determined; according to the maximum voltage limit, the maximum power limit, and the grid fluctuation limit of the plurality of converter modules, constraint conditions are determined; based on the constraint conditions, cross mutation is performed on the initial control decision to obtain a control decision mutation domain; based on the objective function, the control optimization strategy is determined in the control decision mutation domain.

[0013] Second aspect, the present application also provides a cooperative control system for a multi-module converter, which is used to execute the cooperative control method of the multi-module converter as described in the first aspect. Wherein, the cooperative control system of the multi-module converter includes: a converter information acquisition module, which is used to acquire multiple real-time operating states and multiple real-time loads of multiple converter modules; a working mode determination module, which is used to call the user load demand and determine the converter working mode based on the multiple real-time loads; an initial strategy generation module, which is used to generate an initial control strategy according to the converter working mode and in combination with the multiple real-time operating states; a strategy optimization module, which is used to optimize the initial control strategy according to the cooperative control target to obtain an optimized control strategy; a frame construction module, which is used to construct a standard frame based on the optimized control strategy to perform modular management of the converter.

[0014] One or more technical solutions provided in the present application have at least the following beneficial effects:

[0015] By acquiring multiple real-time operating states and multiple real-time loads of multiple converter modules; calling the user load demand and determining the converter working mode based on the multiple real-time loads; generating an initial control strategy according to the converter working mode and in combination with the multiple real-time operating states; optimizing the initial control strategy according to the cooperative control target to obtain an optimized control strategy; constructing a standard frame based on the optimized control strategy to perform modular management of the converter. That is to say, by the real-time loads, operating states of multiple converter modules and the user load demand, the working mode of the converter is adjusted in real time, realizing more accurate load distribution and power scheduling, and improving the cooperative control efficiency of the converter.

[0016] The above description is only an overview of the technical solutions of the present application. In order to be able to understand the technical means of the present application more clearly, it can be implemented according to the content of the description. And in order to make the above and other purposes, features and advantages of the present application more obvious and understandable, the following specifically describes the specific embodiments of the present application. It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present application, nor is it used to limit the scope of the present application. Other features of the present application will become easily understood through the following description. Description of the Drawings

[0017] In order to more clearly illustrate the technical solutions in the present application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings described below are only exemplary, and for those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.

[0018] Figure 1Schematic flow chart of the cooperative control method for the multi-module converter of the present application;

[0019] Figure 2 Schematic structural diagram of the cooperative control system for the multi-module converter of the present application.

[0020] Explanation of reference numerals: Converter information acquisition module 11, operating mode determination module 12, initial strategy generation module 13, strategy optimization module 14, chassis construction module 15. Detailed implementation manners

[0021] By providing a cooperative control method and system for a multi-module converter, the present application solves the technical problem in the prior art that due to the relatively fixed power combination mode of the converter, it is difficult to flexibly adjust according to actual requirements, resulting in low efficiency of the cooperative control of the converter. By the real-time load, operating status and user load requirements of multiple converter modules, the operating mode of the converter is adjusted in real time, realizing more accurate load distribution and power scheduling, and improving the efficiency of the cooperative control of the converter.

[0022] Next, the technical solutions in the present application will be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. It should be understood that the present application is not limited by the example embodiments described herein. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present application. Additionally, it should be noted that for the sake of description, only the parts related to the present application are shown in the accompanying drawings rather than all.

[0023] Embodiment 1, please refer to the attached Figure 1 , the present application provides a cooperative control method for a multi-module converter. Among them, the cooperative control method for the multi-module converter is executed by a cooperative control system for a multi-module converter. The cooperative control method for the multi-module converter specifically includes the following steps:

[0024] S100: Obtain multiple real-time operating statuses and multiple real-time loads of multiple converter modules.

[0025] Specifically, the converter module is the core device unit in the energy storage system used to convert direct current (DC) into alternating current (AC). In a multi-module converter system, multiple converter modules can work together in parallel or series to meet higher power requirements or improve system reliability. The real-time operating state refers to the various parameters that continuously change during the actual operation of the converter module, such as output power, voltage, current, temperature, etc. The real-time operating state reflects the operating health status and working efficiency of each converter module. The real-time load refers to the power demand connected to the converter system at the current moment, usually expressed in power (watts or kilowatts). The load changes at any time. For example, during the day and night or under different weather conditions, the power demands of household or industrial equipment are different.

[0026] By integrating sensors and data acquisition modules, monitor parameters such as the output voltage, output current, power, and possibly temperature of each module, and transmit them to the central control unit. The real-time load refers to the magnitude of the current power demand, monitor the real-time changes of each load, and transmit the load data in real time. By obtaining the real-time operating state and real-time load of multiple converter modules, accurately understand the working conditions of each module and the load demand, ensure that the converter can dynamically adapt to different load demands and working environments, and avoid problems such as power waste and module overload caused by load fluctuations or abnormal module states.

[0027] S200: Invoke the user load demand, and based on the multiple real-time loads, determine the converter operating mode.

[0028] Furthermore, S200 of this application includes:

[0029] According to the user load demand, extract the maximum load power, average load power, and output voltage range; obtain the multiple rated powers and multiple voltage ranges of the multiple converter modules; determine the number of converters according to the maximum load power, the average load power, and the multiple rated powers; according to the output voltage range and the multiple voltage ranges, in combination with the number of converters, determine the converter operating mode, where the converter operating mode includes a parallel operating mode, a series operating mode, and a hybrid operating mode.

[0030] Specifically, the user load demand refers to the actual power demand of the load side (such as communication base stations, IDC data centers, etc.), which usually includes the maximum power demand, average power demand, and voltage demand. The load demand is the core reference factor for the design and control of the converter modular plug-in frame solution. For example, communication base stations, IDC data centers, household equipment, small industrial and commercial energy storage sites, etc. all have different power demands. The maximum power demand of the user load refers to the maximum power load that needs to be borne during a specific period, and usually the maximum load power appears during the load peak period of the system. The average load power refers to the average power demand of the load within a certain time period. Compared with the maximum load power, the average load power can better reflect the stable power demand in the long term. The output voltage range refers to the interval of voltage values that it can output, including direct current voltage (DC) and alternating current voltage (AC), which respectively meet the load demands of different types. For example, assuming that the maximum load power demand of a communication machine room is 6 kW, the average load power demand is 4 kW, and the voltage demand is AC220V, it is necessary to ensure that the converter can provide at least 6 kW of power and the output voltage can meet the requirements of AC220V.

[0031] According to the factory instructions of the converter module, determining the rated power and voltage range of the converter module, that is, the output power and voltage range that the converter can continuously provide under standard working conditions, helps to judge whether multiple converter modules are needed to meet the load demand. The rated power of the converter module is usually 3 - 5 kW, and its voltage range includes direct current (DC40 - 400V) and alternating current (AC220V / AC380V).

[0032] Determine the minimum number of converters required by dividing the maximum load power by the rated power of a single converter module. Divide the average load power by the rated power of a single converter module to determine the number of converters required under normal circumstances. After determining the number of converters, select a suitable working mode according to the voltage demand of the user load and the voltage range of each converter module. If the load requires a higher voltage, it may be necessary to connect the converter modules in series; if the load requires a higher current, a parallel working mode can be adopted. The hybrid working mode is suitable for situations where both a higher voltage and a larger current are required simultaneously.

[0033] In the parallel working mode, multiple converter modules work in parallel, the output currents are combined but the voltage remains the same, which is suitable for scenarios with a higher current demand; in the series working mode, multiple converter modules work in series, the output voltages are superimposed, but the current remains the same. This mode is suitable for load demands that require a higher voltage; the hybrid working mode combines the parallel and series modes, with both parallel and series combinations of modules, adapting to more complex load demands and being suitable for scenarios where both voltage and current need to be considered.

[0034] Flexibly determine the required number of converter modules and select a suitable operating mode based on the user's load demand, the rated power of the converter module, and the voltage range. Through reasonable power distribution and operating mode selection, the problems of overload or voltage mismatch in a single operating mode are avoided, and the energy efficiency and reliability of the converter module are improved.

[0035] Furthermore, the present application further includes the following steps:

[0036] Calculate the mean value of the multiple rated powers to obtain the rated average power; calculate the first converter number based on the maximum load power and the rated average power, and at the same time, calculate the second converter number based on the average load power and the rated average power; obtain the load fluctuation sequence from the central control unit and calculate the load factor; if the load factor is greater than or equal to the preset threshold, use the first converter number as the converter number; if the load factor is less than the preset threshold, use the second converter number as the converter number.

[0037] Specifically, the rated power of each converter module is within a standard range but there are certain differences. Therefore, it is necessary to calculate the average value of the rated powers of all converter modules. For example, assume there are 5 converter modules with rated powers of 4kW, 4.5kW, 4kW, 5kW, and 4.5kW respectively. Then the rated average power is 4.4kW, which is used to evaluate the overall power capacity of the converter to provide a standard value for subsequent calculations.

[0038] Calculate the required number of converters based on the user load demand and the rated average power. Calculate the first converter number through the ratio of the maximum load power to the rated average power, that is, the number of converters required in the extreme load case. Calculate the second converter number through the ratio of the average load power to the rated average power, which is the number of converters required in the normal load case. The first converter number is to ensure that the system can cope with scenarios with large load fluctuations. The second converter number is used when the load fluctuation is normal or the load demand is low.

[0039] The central control unit is a controller responsible for monitoring the system, scheduling, and optimization. It receives the operation data of each module in real time and adjusts the converter configuration according to the load demand. Obtain the load fluctuation sequence from the central control unit, which is usually the load power change data in the past period of time. Calculate the load factor by calculating the average load and the maximum load of this sequence. The load factor is the ratio of the average load to the maximum load, which is used to reflect the volatility of the load. For example, assume the maximum load power in the past period of time is 8kW and the average load power is 6kW. Then the load factor is 0.75.

[0040] Based on past load data, a threshold is set. If the load exceeds this threshold, it is considered an extreme load; if it is lower than the threshold, it is considered a normal load. For example, the average value of the load power over a past period of time is such that a load fluctuation range within 90% is a normal load; when the load power exceeds 90% of the past load peak, i.e., there is a short-term load surge, it is an extreme load. By obtaining the load fluctuation sequence in real time and calculating the load factor, the trend of load change is judged, so as to flexibly adjust the number of converters and the working mode, avoid unnecessary resource waste, reduce energy loss, and effectively improve the energy efficiency of the system.

[0041] S300: Generate an initial control strategy according to the converter working mode and in combination with the multiple real-time operating states.

[0042] Furthermore, S300 of the present application includes:

[0043] Step a: Obtain a first real-time operating state from the multiple real-time operating states and upload it to the central control unit through a communication interface for judgment; Step b: If the first real-time operating state does not meet the preset state, remove the first converter module corresponding to the first real-time operating state; For the multiple real-time operating states, repeat Steps a to b to obtain multiple preferred converter modules that all meet the preset state; Obtain external power grid information from the central control unit; Generate the initial control strategy according to the converter working mode, the multiple preferred converter modules, and in combination with the external power grid information.

[0044] The external power grid information includes grid voltage fluctuation, grid load fluctuation, and grid frequency fluctuation.

[0045] Specifically, randomly select one from the multiple real-time operating states as the first real-time operating state, including parameters such as the current, voltage, and power of the corresponding converter module. The data can be uploaded to the central control unit through a communication interface (such as Modbus, CAN bus, etc.). The preset state refers to a specific operating state that a converter module should reach as predefined according to design or operation requirements. For example, a temperature range, a power output range, etc. can be set as standards. If the operating state of the converter does not meet these standards, it is considered not to meet the preset state.

[0046] The central control unit will judge the uploaded first real-time operating state. If the first real-time operating state does not meet the preset state, it means that the operating state of this sensor module does not meet the preset requirements. The central control unit will decide to remove this converter module, that is, exclude this module from the coordinated control. Continue to obtain the real-time states from other converter modules and repeat Steps a and b until all converter modules that meet the preset requirements are screened out.

[0047] By repeatedly performing Step a and Step b, multiple preferred converter modules are screened out, and these modules meet the preset operating state requirements. For example, among a group of 5 converter modules, 3 converters meet the preset state, while 2 converters do not meet the requirements. Eventually, the 3 converter modules that meet the conditions will be retained. The converter obtains external grid information through measurement sensors, communication interfaces, or the grid dispatching system. The converter will regularly request this external grid data from the central control unit or the dispatching system to adjust the operating strategy in real time. The external grid information refers to the relevant data from the grid side, including grid voltage, grid frequency, load demand, power supply quality, etc. Based on this information, the converter adjusts its own operating strategy according to the changes in the external grid.

[0048] Grid voltage fluctuation refers to the degree of change in the grid output voltage within a certain period of time. Voltage fluctuations may be caused by load changes, equipment failures, or other external factors. Excessive grid voltage fluctuations may affect the normal operation of the converter, so real-time monitoring is required. Grid load fluctuation refers to the change in the load demand in the grid. As the power consumption demand of users changes, the load on the grid will also fluctuate accordingly. Grid frequency fluctuation refers to the change in the grid frequency within a certain period of time. Generally, the grid frequency should be maintained at 50Hz or 60Hz (depending on the region).

[0049] Based on the determined converter operating mode, as well as the number and capabilities of the converter modules required for this operating mode, the final control strategy is determined from the multiple preferred converter modules that have been screened out. If there are multiple eligible preferred converter modules, select the parallel, series, or hybrid mode to achieve the required power output and voltage requirements. For example, assume that a higher voltage output is required, but the load demand is large. Select to operate multiple converter modules in series (series operating mode) to provide a high voltage output and ensure voltage stability.

[0050] Through the preferred modules, the central control unit can understand the real-time status of each converter (such as power output, voltage, current, etc.) and select the best combination of converters to meet the load demand. After obtaining the external grid information, the central control unit will further adjust the strategy. For example, if the grid voltage fluctuates greatly (for example, the voltage fluctuates between DC48V and DC45V), the system output voltage is stabilized by increasing the parallel modules or adjusting the module operating mode.

[0051] The central control unit generates an initial control strategy based on all the information, defining the operating mode of the converter, the combination of modules, the power distribution method, and how to respond to grid changes, etc. This is applied to the coordinated control of the converter modules to ensure efficient and stable operation. The initial control strategy is a coordinated control scheme generated according to the operating mode of the converter, the status of the preferred converter modules, and the conditions of the external power grid, mainly used to guide how the converter modules work together to achieve power balance, stable voltage output, and respond to grid fluctuations.

[0052] By obtaining external grid information in real time and flexibly adjusting the operating mode of the converter according to the grid status, it is ensured that when the grid fluctuates or the load changes, the converter can automatically adapt, ensuring that the power and voltage distribution can be optimized according to the load demand and grid conditions, avoiding overload or voltage instability, thus ensuring continuous and stable power supply for the communication base station, and at the same time avoiding the impact of voltage fluctuations on the base station equipment.

[0053] S400: Optimize the initial control decision according to the coordinated control target to obtain a control optimization strategy.

[0054] Furthermore, S400 of this application includes:

[0055] Determine the objective function according to the maximum load adaptation and maximum power efficiency of the coordinated control target; determine the constraint conditions according to the maximum voltage limit, maximum power limit, and grid fluctuation limit of the multiple converter modules; based on the constraint conditions, perform crossover mutation on the initial control decision to obtain a control decision mutation domain; based on the objective function, determine the control optimization strategy in the control decision mutation domain.

[0056] Specifically, the coordinated control target is to make the converter modules achieve an optimized effect while meeting specific requirements through coordinated work in a multi-converter system, including maximum load adaptation and maximum power efficiency, etc. Maximum load adaptation means reasonably allocating and scheduling the converter modules according to the load demand to ensure that the load requirements can be fully met, not only considering the peak value of the load demand, but also considering load fluctuations and stability. Maximum power efficiency means achieving the highest operating efficiency by reasonably configuring the operating mode of the converter modules, adjusting the power distribution, etc., thereby reducing energy loss and achieving an energy-saving effect.

[0057] The objective function is a mathematical expression used to quantify the optimization target. In coordinated control, the objective function usually combines multiple factors, such as load adaptation, power efficiency, etc., to describe the target to be optimized. The objective function needs to consider factors such as load adaptation and power efficiency, and combine different control strategies to obtain a quantified target value. Determine the objective function through the weighted sum of load adaptation and power efficiency.

[0058] Constraints are the limiting factors in the control optimization process, ensuring that the control decisions generated during the optimization process are reasonable and feasible. For example, the maximum voltage constraint ensures that the output voltage of the converter does not exceed the maximum voltage that the device can withstand; the maximum power constraint ensures that the converter does not operate overloaded; the grid fluctuation constraint ensures that the output of the converter can cope with the fluctuations of the external power grid. For example, the output voltage of the converter cannot exceed the rated voltage range of the system (such as 400V); the power output of a single converter cannot exceed its rated power (such as 5kW); it can cope with the grid voltage fluctuation range, such as a ±10% fluctuation.

[0059] Based on the existing initial control strategy, crossover and mutation operations are used to generate new control decisions. Through the crossover operation, the advantages of different control decisions are combined; through the mutation operation, new solutions are explored within the control decision space. Crossover generates a new solution by combining partial information of two solutions, and mutation increases the diversity of the solution space by randomly changing the solution. The combination of the two can effectively explore and optimize the objective function. The control decision mutation domain refers to the set of possible control decisions generated through crossover and mutation operations, representing different control strategies, and further optimization searches can be carried out within it.

[0060] All strategies in the control decision mutation domain are evaluated based on the objective function to find the optimal control decision, which is the so-called control optimization strategy, that is, the final solution optimized through multiple crossover and mutation operations. On the basis of meeting all constraints, it can achieve the maximization of load adaptation and power efficiency. Through optimization operations such as crossover and mutation, the load adaptation and power efficiency are maximized according to the objective function, and the optimal control strategy is found to ensure that all constraints are met, such as the maximum voltage constraint, the maximum power constraint, etc., avoiding the risks of system overload or instability.

[0061] S500: Based on the control optimization strategy, a standard chassis is constructed to manage the converters modularly.

[0062] The standard chassis includes slots, bus power supplies, control modules, lightning protection modules, disconnectors, power meter contactors, multiple converter modules, and shunts.

[0063] Specifically, based on the optimized control optimization strategy, a standardized chassis system is constructed to achieve modular management of converter modules. Through the design of the standard chassis, the working states, maintenance, and expansion of multiple converter modules are organized and controlled. The most suitable control scheme, such as parallel, series, or hybrid working modes, is determined through the optimization algorithm to decide the working states of the converter modules and their output power characteristics.

[0064] A standard subrack is a preset hardware framework used to accommodate and manage multiple converter modules. It provides standardized slots, connection ports, etc., so that converter modules can be easily installed, removed, and maintained, thereby achieving modular management. Standard subracks are usually designed with a modular structure to support rapid expansion or replacement of converter modules.

[0065] The standard subrack includes slots, convergence power supply, control module, lightning protection module, isolating switch, power meter contactor, multiple converter modules, and shunt. The slot is a space specially designed for installing converter modules in the standard subrack. Each slot can accommodate a converter module, ensuring that the converter module can be easily inserted or removed while maintaining good electrical connection. The convergence power supply is to centrally connect the power inputs of multiple converter modules and converge the power lines of multiple converter modules to a common power line for easy power distribution and management. The control module is responsible for the control and monitoring functions of the entire standard subrack system. Through communication with the converter module, it realizes the scheduling, coordination and status monitoring of the converter module to ensure that the converter module works according to the optimized control strategy. The lightning protection module is used to protect the converter module from lightning strikes and overvoltage. It usually includes a lightning arrester and an overvoltage protection device to prevent the lightning current in the power grid or external power supply from damaging the system. The isolating switch is used to cut off the current flow to the module when the converter module fails or needs maintenance, thereby ensuring safe operation and isolating the power supply to prevent other parts of the system from being affected.

[0066] Power meter contactors are used to monitor parameters such as current, voltage and power, and measure power consumption in real time through connection with the meter. They are usually integrated in the converter module to provide real-time data of system operation. The converter module is a device used to convert direct current (DC) to alternating current (AC) or convert alternating current (AC) to direct current (DC). The shunt is a device used to distribute current to multiple converter modules or different circuits, ensuring that the current is evenly distributed between different modules, thereby achieving load balancing and avoiding overload.

[0067] When used in parallel, the standard subracks can achieve compartment management, single group management, easy maintenance, high safety, and can realize intelligent mixed use and intelligent operation and maintenance functions. They can supply power to the power grid, not only realizing backup power and peak-valley arbitrage, but also responding to power grid dispatch. When used in series, the standard subracks can meet the highest voltage DC400V series connection, and support up to 7 boxes in series to reduce current. The converter modules can be used in parallel to achieve capacity expansion, basically solving the application field of small industrial and commercial storage. The converter modules can realize modular management and increase power.

[0068] Through the standard plug-in frame, all converter modules can be easily managed. Different modules work together according to the control optimization strategy, enabling flexible expansion and replacement, and making the maintenance, monitoring, and management of the system more convenient. Through the standardized plug-in frame design, the converter modules can be conveniently added or reduced according to actual needs, supporting flexible expansion and replacement. Each converter module and related components (such as power supply, control module, etc.) are uniformly managed through the slot method, facilitating installation, replacement, and maintenance.

[0069] In summary, the collaborative control method of the multi-module converter provided by this application has the following beneficial effects:

[0070] By obtaining the multiple real-time operating states and multiple real-time loads of multiple converter modules; invoking the user load demand, determining the converter operating mode based on the multiple real-time loads; generating an initial control strategy according to the converter operating mode and combining the multiple real-time operating states; optimizing the initial control strategy according to the collaborative control target to obtain a control optimization strategy; and constructing a standard plug-in frame based on the control optimization strategy to perform modular management of the converter. That is to say, through the real-time loads, operating states, and user load demands of multiple converter modules, the operating mode of the converter is adjusted in real time to achieve more precise load distribution and power scheduling, improving the collaborative control efficiency of the converter.

[0071] Embodiment 2, based on the same inventive concept as the collaborative control method of the multi-module converter in the foregoing Embodiment 1, this application also provides a collaborative control system for a multi-module converter. Please refer to the appendix Figure 2 , the collaborative control system of the multi-module converter includes:

[0072] A converter information acquisition module 11 for obtaining the multiple real-time operating states and multiple real-time loads of multiple converter modules; a working mode determination module 12 for invoking the user load demand and determining the converter working mode based on the multiple real-time loads; an initial strategy generation module 13 for generating an initial control strategy according to the converter working mode and combining the multiple real-time operating states; a strategy optimization module 14 for optimizing the initial control strategy according to the collaborative control target to obtain a control optimization strategy; and a plug-in frame construction module 15 for constructing a standard plug-in frame based on the control optimization strategy to perform modular management of the converter.

[0073] Furthermore, the working mode determination module 12 in the collaborative control system of the multi-module converter is further used for:

[0074] According to the user load demand, extract the maximum load power, average load power, and output voltage range; obtain the multiple rated powers and multiple voltage ranges of the multiple converter modules; determine the number of converters according to the maximum load power, the average load power, and the multiple rated powers; determine the converter operating mode according to the output voltage range and the multiple voltage ranges, in combination with the number of converters, where the converter operating mode includes a parallel operating mode, a series operating mode, and a hybrid operating mode.

[0075] Further, the operating mode determination module 12 in the collaborative control system of the multi-module converter is further configured to:

[0076] Calculate the average value of the multiple rated powers to obtain the rated average power; calculate a first number of converters according to the maximum load power and the rated average power, and at the same time, calculate a second number of converters according to the average load power and the rated average power; obtain a load fluctuation sequence from the central control unit and calculate a load factor; if the load factor is greater than or equal to a preset threshold, use the first number of converters as the number of converters; if the load factor is less than the preset threshold, use the second number of converters as the number of converters.

[0077] Further, the initial strategy generation module 13 in the collaborative control system of the multi-module converter is further configured to:

[0078] Step a: Obtain a first real-time operating state from the multiple real-time operating states, and upload it to the central control unit through a communication interface for judgment; Step b: If the first real-time operating state does not meet the preset state, remove the first converter module corresponding to the first real-time operating state; for the multiple real-time operating states, repeat steps a to b to obtain multiple preferred converter modules that all meet the preset state; obtain external power grid information from the central control unit; generate the initial control strategy according to the converter operating mode, the multiple preferred converter modules, in combination with the external power grid information.

[0079] Further, the initial strategy generation module 13 in the collaborative control system of the multi-module converter is further configured to:

[0080] The external power grid information includes grid voltage fluctuation, grid load fluctuation, and grid frequency fluctuation.

[0081] Further, the strategy optimization module 14 in the collaborative control system of the multi-module converter is further configured to:

[0082] Determine the objective function according to the maximization of load adaptation and the maximization of power efficiency of the collaborative control target; determine the constraint conditions according to the maximum voltage limit, the maximum power limit and the grid fluctuation limit of the multiple converter modules; based on the constraint conditions, perform crossover mutation on the initial control decision to obtain the control decision mutation domain; based on the objective function, determine the control optimization strategy in the control decision mutation domain.

[0083] Further, the chassis construction module 15 in the collaborative control system of the multi-module converter is further configured to:

[0084] The standard chassis includes slots, busbar power supplies, control modules, lightning protection modules, isolators, power meter contactors, multiple converter modules, and shunts.

[0085] The various embodiments in this specification are described in a progressive manner, and the key point of each embodiment is the difference from other embodiments. The Figure 1 The collaborative control method and specific examples of the multi-module converter in the first embodiment are equally applicable to the collaborative control system of the multi-module converter in this embodiment. Through the above detailed description of the collaborative control method of the multi-module converter, those skilled in the art can clearly know the collaborative control system of the multi-module converter in this embodiment. Therefore, for the sake of simplicity of the specification, it will not be described in detail here. For the system disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the description of the method part.

[0086] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0087] Obviously, for those skilled in the art, without departing from the principle of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the protection scope of the present application.

Claims

1. A cooperative control method for a multi-module converter, characterized in that, Including: Obtain the multiple real-time operating states and multiple real-time loads of multiple converter modules; Call the user load demand, and determine the converter operating mode based on the multiple real-time loads; Generate an initial control strategy according to the converter operating mode and in combination with the multiple real-time operating states; Optimize the initial control strategy according to the collaborative control target to obtain a control optimization strategy; Based on the control optimization strategy, construct a standard plug-in frame to perform modular management on the converter.

2. The collaborative control method of the multi-module converter according to claim 1, characterized in that The standard plug-in frame includes slots, busbar power supplies, control modules, lightning protection modules, disconnectors, power meter contactors, multiple converter modules, and shunt resistors.

3. The collaborative control method of the multi-module converter according to claim 1, characterized in that, Call the user load demand, and determine the converter operating mode based on the multiple real-time loads, including: Extract the maximum load power, average load power, and output voltage range according to the user load demand; Obtain the multiple rated powers and multiple voltage ranges of the multiple converter modules; Determine the number of converters according to the maximum load power, the average load power, and the multiple rated powers; Determine the converter operating mode according to the output voltage range and the multiple voltage ranges, in combination with the number of converters, where the converter operating mode includes a parallel operating mode, a series operating mode, and a hybrid operating mode.

4. The collaborative control method of the multi-module converter according to claim 3, characterized in that, Determine the required number of converters according to the maximum load power, the average load power, and the multiple rated powers, including: Calculate the average value of the multiple rated powers to obtain the rated average power; According to the maximum load power and the rated average power, calculate the first number of converters, and at the same time, according to the average load power and the rated average power, calculate the second number of converters; Obtain the load fluctuation sequence from the central control unit and calculate the load factor; If the load factor is greater than or equal to the preset threshold, use the first number of converters as the number of converters; If the load factor is less than the preset threshold, use the second number of converters as the number of converters.

5. The collaborative control method of the multi-module converter according to claim 4, characterized in that, Generate an initial control strategy according to the converter operating mode and in combination with the multiple real-time operating states, including: Step a: Obtain the first real-time operating state from the multiple real-time operating states and upload it to the central control unit for judgment through the communication interface; Step b: If the first real-time operating state does not meet the preset state, remove the first converter module corresponding to the first real-time operating state; For the multiple real-time operating states, repeat steps a to b to obtain multiple preferred converter modules that all meet the preset state; Obtain the external power grid information from the central control unit; Generate the initial control strategy according to the converter operating mode, the multiple preferred converter modules, and in combination with the external power grid information.

6. The collaborative control method of the multi-module converter according to claim 5, wherein The external power grid information includes grid voltage fluctuation, grid load fluctuation, and grid frequency fluctuation.

7. The collaborative control method of the multi-module converter according to claim 1, characterized in that, Optimize the initial control strategy according to the collaborative control target to obtain a control optimization strategy, including: Determine the objective function according to the load adaptation maximization and power efficiency maximization of the collaborative control target; Determine the constraint conditions according to the maximum voltage limit, maximum power limit and grid fluctuation limit of the multiple converter modules; Based on the constraint conditions, perform crossover mutation on the initial control strategy to obtain a control decision mutation domain; Based on the objective function, determine the control optimization strategy in the control decision mutation domain.

8. Cooperative control system for multi-module converters, characterized in that, For implementing the steps of the cooperative control method of the multi-module converter according to any one of claims 1 to 7, the cooperative control system of the multi-module converter includes: A converter information acquisition module, configured to acquire multiple real-time operating states and multiple real-time loads of multiple converter modules; A working mode determination module, configured to call the user load demand and determine the converter working mode based on the multiple real-time loads; An initial strategy generation module, configured to generate an initial control strategy according to the converter working mode and in combination with the multiple real-time operating states; A strategy optimization module, configured to optimize the initial control strategy according to the cooperative control objective to obtain a control optimization strategy; A chassis construction module, configured to construct a standard chassis based on the control optimization strategy for modular management of the converter.

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