A method of powering an electric vehicle charging device

Abstract

The application discloses an energy supply method of an electric vehicle charging device, and relates to the technical field of electric vehicle charging, which calculates the charging urgency and the fairness demand weight according to the real-time state of charge of the charging vehicle, the battery chemical characteristics, the off-site time and other parameters, and dynamically distributes the total power of the shared power pool according to the weight, converts the distributed power into the target duty cycle of the power module, and performs stepwise smooth adjustment, so as to realize the non-inductive switching among the power modules, and inhibit the harmonics and three-phase imbalance in combination with the multi-module staggered phase shift control. The method solves the problems of unfair resource distribution, switching interruption and power grid impact in the multi-vehicle shared charging scene, and can be used for the power scheduling control of the centralized charging pile.

Description

Technical Field

[0001] This invention relates to the field of electric vehicle charging technology, specifically to a power supply method for electric vehicle charging equipment. Background Technology

[0002] With the rapid growth of the number of new energy electric vehicles, the demand for high-power fast charging and supercharging is increasing. In order to improve the utilization rate and return on investment of charging station equipment, the industry generally adopts the centralized charging pile mode of group management and control. This mode consists of multiple standardized AC and DC power modules forming a shared power pool. Through the unified scheduling of the main controller, the power is allocated to each charging port as needed, realizing the dynamic reuse of power resources. The vehicle and the charging pile communicate according to the national standard "Communication Protocol between Electric Vehicle Off-board Conductive Charger and Battery Management System". The charging pile obtains parameters such as the real-time state of charge, upper limit of charging voltage, and upper limit of charging current of the vehicle by receiving messages sent by the vehicle's battery management system.

[0003] The main functional allocation methods used by the mainstream centralized charging piles on the market include: the charging pile main controller periodically scans the connection status of each charging port. When the grid issues a total power limit command or the total capacity of the power pool is insufficient, the controller allocates the total power equally or proportionally to each charging vehicle according to the first-come-first-served priority or the number of connected vehicles. For scenarios where the power of a certain port needs to be readjusted, some manufacturers use a relay matrix structure to recombine the connection relationship between the power module group and the charging port through physical contact switching. Before the switching action, the current of the port must be reduced to zero and the charging handshake must be disconnected. After the relay action is completed, the vehicle-pile handshake is re-established and charging is resumed. The structure of the above solution mainly includes an AC power distribution cabinet, multiple standardized power modules, a relay matrix or contactor group, a main controller, multiple charging ports, and a vehicle battery management system communication interface. The various parts are connected through a power bus and a communication bus. The main controller issues control commands to the power modules and switching devices according to the preset allocation strategy.

[0004] The aforementioned existing technical solutions have the following drawbacks: First, because the existing solutions adopt fixed timing priorities or average allocation strategies, they cannot identify differences in state of charge, battery chemical characteristics, and the urgency of user departure times among different vehicles. This results in emergency charging vehicles, which should receive priority for higher power, not receiving sufficient power support, while vehicles that are nearly fully charged and have very low power requirements occupy power resources. This leads to significant differences in charging time among different vehicles within the same charging pile and a poor user experience. Second, because the relay matrix relies on physical contacts for power redistribution, the physical contacts are difficult to switch directly under current flow conditions. Each adjustment of power distribution requires first reducing the target nozzle current to zero and... Interrupting the charging session and waiting for the relay to complete its operation before re-handshaking will give users a negative perception of charging interruption. At the same time, frequent contact switching will accelerate arc erosion, shorten the life of the relay, and increase maintenance costs. Thirdly, when the total demand exceeds the grid's allowable capacity, the traditional method generally adopts the approach of proportionally derating all charging ports without coordinating and controlling the switching sequence of the power modules. Under the condition of multiple charging ports in parallel and drastic load dynamic changes, large current jumps and switching harmonic superposition can easily occur instantaneously, which can lead to transient harmonic impacts, three-phase imbalances, and voltage deviations in the upstream distribution network, affecting the reliability of regional power supply. Therefore, we propose a power supply method for electric vehicle charging equipment. Summary of the Invention

[0005] The purpose of this invention is to provide a power supply method for electric vehicle charging equipment.

[0006] The technical problem this invention aims to solve is that in a shared power pool architecture scenario where multiple vehicles share the same charging pile, existing power allocation methods cannot perform reasonable dynamic power allocation based on the multi-dimensional differentiated needs of vehicles, such as real-time battery status, battery chemical characteristics, and user departure time. This results in some vehicles monopolizing power resources while the power needs of others are not met. At the same time, existing hardware relay switching power redistribution schemes cause charging interruptions and hardware losses, while traditional proportional derating methods are prone to grid harmonic impacts and three-phase imbalance problems.

[0007] To address the aforementioned technical problems, this invention provides a power supply method for electric vehicle charging equipment, comprising: periodically acquiring messages sent by the battery management systems of each vehicle connected to the charging pile via a communication interface; parsing the real-time state of charge, the upper limit of the charging rate corresponding to the battery chemistry type, the battery capacity, the upper limit of the charging voltage, and the upper limit of the charging current for each vehicle, as well as the user-preset departure time; calculating the charging urgency parameter and power upper limit for each vehicle based on the above parameters; calculating the normalized fairness demand weight for each vehicle based on the charging urgency parameter and the real-time state of charge; obtaining the total power that the shared power pool can output; allocating the total power according to the fairness demand weight; redistributing the remaining power corresponding to vehicles that have not exhausted their weight share due to reaching the power upper limit within the set of unsaturated vehicles according to the weight ratio; iterating repeatedly until convergence to obtain the allocated power for each vehicle; converting the allocated power into the target duty cycle of the corresponding power module; and controlling the power module... The actual output duty cycle of the module is gradually adjusted towards the target duty cycle according to the preset single-step increment, and closed-loop correction is performed in combination with current and voltage feedback to ensure that the output power of the power module smoothly transitions to the allocated power without interrupting the established charging handshake session. When the power source of a charging port needs to be switched between different power modules, the newly connected power module is controlled to gradually increase from zero duty cycle to take over the load, while the duty cycle of the original power module is controlled to decrease synchronously at the same rate to keep the output current of the port continuous. The power upper limit command issued by the grid dispatch is obtained. When the sum of the allocated power of all charging vehicles exceeds the power upper limit command, the scaling factor is calculated and the allocated power is corrected proportionally to obtain the execution power command of each charging vehicle. Different switching phase offset angles are assigned to each power module participating in the output, and the power modules are controlled to turn on and off in sequence in a staggered manner. The degree of imbalance of the three-phase input current is monitored in real time, and the three-phase access ratio of each power module is dynamically adjusted to make the three-phase load tend to be balanced.

[0008] Compared with the prior art, the beneficial effects of the present invention by adopting the above technical solution are as follows:

[0009] 1. This invention constructs an urgency index and fairness demand weight calculation model that integrates multi-dimensional parameters such as state of charge, battery chemical characteristics, battery capacity, and off-site time. It adopts a convergent allocation mechanism that combines initial allocation with iterative redistribution of remaining power of saturated vehicles. This is different from the technical path of fixed time priority or average allocation in the prior art. It enables the power allocation to fully reflect the real urgent needs of each vehicle, solves the resource mismatch problem, and improves the overall resource utilization efficiency and user satisfaction.

[0010] 2. This invention avoids hard switching of physical relays by designing a flexible power routing control strategy based on duty cycle incremental steps, realizing smooth power transfer between power modules, enabling users to complete power source allocation without noticing, avoiding charging interruptions, and extending the service life of the equipment;

[0011] 3. This invention employs a multi-module staggered phase shifting active shaping power supply strategy combined with real-time monitoring and adjustment of three-phase imbalance. While ensuring fair allocation among multiple vehicles, it actively suppresses harmonics and three-phase imbalance, protecting the power quality of the power grid. This achieves a unified optimization of power supply fairness, power switching continuity, equipment reliability, and grid friendliness. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the multidimensional dynamic power allocation calculation process in an embodiment of the present invention;

[0013] Figure 2 This is a schematic diagram of the flexible power seamless switching control process in an embodiment of the present invention;

[0014] Figure 3 This is a schematic diagram of the active shaping process for power grid harmonics and three-phase imbalance in an embodiment of the present invention. Detailed Implementation

[0015] The following is in conjunction with the appendix Figure 1-3 The specific embodiments of the present invention will be further described below. It should be noted that the description of these embodiments is for the purpose of helping to understand the present invention, but does not constitute a limitation of the present invention.

[0016] Furthermore, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0017] The power supply method for electric vehicle charging equipment provided by this invention relies on a hardware and information interaction architecture including an AC power distribution cabinet, a shared power pool composed of multiple standardized AC / DC power modules, an edge computing master control node, and multiple charging ports. Each charging port is connected to the on-board battery management system of the corresponding electric vehicle. The number of power modules in the shared power pool is denoted as follows: The number of charging gun ports is recorded as , and All values ​​are positive integers greater than 1. The power module pool and each charging port are connected via a power bus. Power can be flexibly routed between modules and ports rather than being fixed. Each charging port interacts with the battery management system of the connected vehicle through the aforementioned communication protocol, collecting parameters such as real-time state of charge, maximum allowable charging current and voltage, and battery chemical type identification. The data is then uploaded to the edge computing master control node. The edge computing master control node also receives total power limit commands issued by the grid dispatch in real time. The master control node has three functional modules: a dynamic power demand assessment module, a flexible power routing control module, and an active shaping and suppression module. These three modules form a closed loop relationship through sequential data flow. Finally, the duty cycle and phase shift control commands of each power module are output to the shared power pool. The entire method runs in a millisecond cycle, forming a complete closed-loop control of perception, decision-making, execution, and feedback.

[0018] I. Dynamic Power Demand Assessment Based on Multi-Dimensional Feature Fusion:

[0019] The edge computing master node reads the battery management system messages of the N vehicles currently charging via the communication interface at a preset period, such as every 200 milliseconds. It then parses these messages to obtain the real-time state of charge (SOC) of each vehicle, the upper limit of the charging rate corresponding to the battery chemistry type, the battery capacity, the upper limit of the charging voltage and charging current, and the user's preset departure time when charging is initiated. The information is then labeled... Indicates the vehicle number. The value ranges from 1 to Integers;

[0020] The master node calculates the first according to the following formula. Vehicle charging urgency parameters:

[0021] ;

[0022] in, Indicates the first The vehicle's charging urgency level is indicated by a higher value, meaning the vehicle needs a greater amount of electricity to be replenished within the remaining charging time. The target state of charge preset by the user, This represents the current real-time state of charge. Battery capacity, in kilowatt-hours. Preset departure time for users. The current system time is given, and the difference between the two represents the remaining time before the vehicle leaves the site.

[0023] The master control node calculates the first step based on the battery's chemical characteristics and hardware limitations using the following formula. The current acceptable power limit for the vehicle:

[0024] ;

[0025] in, For the first The current safe upper limit of power for vehicle batteries. This represents the upper limit of the charging rate corresponding to the battery chemistry system of this vehicle. This refers to the upper limit of the battery charging voltage. The upper limit of the battery charging current is determined by taking the smaller of the products of the two items mentioned above. This is to take into account both the rate limit imposed by the battery chemistry system and the voltage and current limit imposed by the hardware circuitry, so as to avoid exceeding the safe tolerance range of the vehicle battery.

[0026] Based on this, the master control node calculates the normalized fairness demand weight for each vehicle by combining the charging urgency parameter with the current battery level using the following formula:

[0027] ;

[0028] in, For the first The fairness requirement weight after vehicle normalization has a value range of greater than 0 and less than 1, and the sum of the weights of all charging vehicles is 1. It is a preset, extremely small positive number used to avoid when The calculation anomaly is caused by the denominator being zero when the value is zero. The two terms in the numerator reflect the time urgency of the vehicle and the contribution of the current power level to the fairness of the allocation. The lower the state of charge of the vehicle, the higher its weight component, so that vehicles with less power can also obtain relatively sufficient power support under the same urgency conditions.

[0029] The master node further obtains the total power that the current shared power pool can output externally. The total power is determined by the smaller of the total power limit command issued by the power grid dispatch and the rated capacity of the power module pool itself, and is initially allocated according to the weights:

[0030] ;

[0031] in, For the first The initial power allocated to a vehicle in this round of allocation may exceed its own power limit for some vehicles. In this case, the vehicle can only receive the power limited by its power limit, and the power corresponding to the remaining weight share will be temporarily idle. To fully utilize the total power of the shared power pool, the master node determines whether there are any vehicles that have not exhausted their allocated weight share due to reaching their power limit. If there is remaining power, it is redistributed again according to the weight ratio within the set of vehicles that are not yet saturated. This process is repeated until the remaining power is less than a preset threshold or all vehicles have reached their respective power limits. The iteration formula is as follows:

[0032] ;

[0033] ;

[0034] in, This represents the remaining available power that has not yet been allocated in the current round. After redistribution, the first Vehicle replacement power, The set of vehicles that have not yet reached their respective power limits. This is an indicator function that takes the value 1 when the condition within the parentheses is true, and 0 otherwise. Its function is to allocate remaining power only to vehicles that are not yet saturated. For example, if three vehicles are connected to a charging pile, and one vehicle has a low state of charge and a short remaining time away from the site, its charging urgency parameter is correspondingly higher, allowing it to obtain a relatively larger initial allocation power during weight calculation and power allocation. If another vehicle fails to exhaust its weight share due to a lower power limit caused by its battery chemistry, this remaining power will be redistributed to the remaining unsaturated vehicles using the iterative method described above. This ensures fairness while fully utilizing the total power resources of the shared power pool, ultimately converging the allocated power for each vehicle. This serves as the input basis for the seamless switching control of flexible power routing;

[0035] The process includes periodically collecting battery management system messages from each vehicle, calculating the charging urgency parameters for each vehicle, calculating the power upper limit for each vehicle, calculating the fairness demand weight for each vehicle, obtaining the total available power of the shared power pool, performing initial power allocation according to the weights, determining whether there are saturated vehicles and remaining power, and iteratively redistributing the power based on this, until convergence and outputting the final power allocation result.

[0036] II. Flexible Power Routing and Seamless Switching Control:

[0037] The master control node allocates power to each vehicle. Based on the vehicle's current charging voltage, calculate the target duty cycle that the corresponding power module group should output. Subsequently, the master control node adjusts the current actual output duty cycle towards the target duty cycle in a gradual, step-by-step manner at a fixed control cycle, such as every 10 microseconds, rather than making a one-time jump. The adjustment formula is as follows:

[0038] ;

[0039] ;

[0040] in, For the first The actual output duty cycle of the power module within each control cycle The duty cycle for the next control cycle. The target duty cycle is calculated as follows: This is the allowable duty cycle increment for this cycle. A pre-set threshold for single-step duty cycle increment is used to limit the slope of current change and avoid sudden current changes. The sign function is used to determine the relationship between the current duty cycle and the target duty cycle, thereby determining the adjustment direction. During the duty cycle step adjustment process, the main control node collects the output current and voltage feedback values ​​of the power module in real time, and corrects the duty cycle command through closed-loop proportional-integral adjustment to ensure that the actual output power smoothly tracks the power allocated to the corresponding vehicle, and the charging handshake session established between the vehicle and the charging pile is not interrupted throughout the process.

[0041] When a charging port needs to switch from its original power module group to another idle power module to obtain power support, the master control node first controls the newly connected power module to gradually increase its duty cycle from zero in the above incremental manner to take over part of the load. At the same time, it controls the original power module to synchronously decrease its output duty cycle at the same rate. The two move in opposite directions to achieve a smooth switching of the power source module. The total output current of the port is kept continuous throughout the process to avoid current drop or charging interruption caused by source module switching. The above duty cycle step adjustment and module switching process is repeated until the actual output power of each charging port converges to the allocated power output by the aforementioned evaluation subsystem, completing one round of seamless power routing adjustment.

[0042] Multiple standardized power modules within the shared power pool are connected to multiple charging ports via a flexible connection switch array. This connection method differs from traditional relay matrices and belongs to power electronic soft switching or dynamic duty cycle adjustment units. The sum of the gradually decreasing duty cycle curve of the original power module and the gradually increasing duty cycle curve of the newly connected power module remains constant, thus demonstrating a seamless switching effect with continuous and uninterrupted total current.

[0043] III. Active shaping power supply to prevent grid impact:

[0044] The master control node obtains the real-time power limit instruction issued by the power grid dispatching system, and summarizes the sum of the power allocated to each vehicle obtained by the aforementioned evaluation subsystem. It then determines whether the total demand exceeds the limit. If the total demand exceeds the power grid limit, the global scaling factor is calculated according to the following formula, and the power allocated to each charging vehicle is proportionally reduced:

[0045] ;

[0046] in Less than 1, the scaled power command for each vehicle is as follows:

[0047] ;

[0048] in, The total power limit threshold issued by the grid side. This is the global scaling factor, which is reduced proportionally. After power grid limitation correction, the data was issued to the first... The power command executed by the corresponding power module group of the vehicle;

[0049] At the actual output level of the power modules, each within the shared power pool... Each standardized power module does not use synchronous switching. Instead, it adopts an interleaved parallel control strategy, assigning different switching phase angles to each module. The phase angle calculation formula is as follows:

[0050] ;

[0051] in, For the first The switching phase offset angle of each power module This represents the total number of power modules participating in this output. The power module is numbered, with values ​​ranging from 1 to... The power modules are turned on and off in a staggered manner according to their assigned phase angles, so that the switching ripple and harmonic components generated by each module are staggered in time and superimposed. The high-frequency harmonic content in the total output current of the shared power pool is reduced through the harmonic cancellation effect. For example, when the number of power modules participating in the output is 4, the switching phase offset angles of the four modules are respectively a quarter of a switching cycle apart, and the switching ripple of each module is uniformly staggered in time. After superposition, the ripple amplitude of the total output current is significantly reduced compared with the synchronous switching method.

[0052] Meanwhile, the main control node monitors the current imbalance on the three-phase input side in real time. When it detects that the current of one phase is significantly higher than that of the other two phases, it dynamically adjusts the distribution ratio of each power module on the three-phase input side, that is, changes the phase sequence distribution weight of each module, so that the three-phase load tends to be balanced. Thus, under the premise of satisfying fair power distribution among multiple vehicles, it actively suppresses the three-phase imbalance and harmonic mutation caused by high-frequency switching of power modules and dynamic load changes. Finally, the duty cycle and phase control parameters of each power module obtained by the above processing are sent to the flexible power routing seamless switching control loop for execution, and periodically return to re-collect the latest status of each vehicle, forming a complete closed-loop control method of acquisition, evaluation, allocation, routing, shaping, execution and feedback.

[0053] The switching drive pulse waveforms of each power module and their staggered phase angles are superimposed to share the total output current waveform of the power pool. This waveform is then compared with the total output current waveform under the traditional synchronous switching method, highlighting the technical effect of the present invention, which significantly reduces the total output ripple amplitude and harmonic content compared to the traditional method.

[0054] IV. Other implementation methods:

[0055] In another implementation, the aforementioned method of calculating the fairness requirement weight can be replaced by a pre-trained strategy network. The state of charge of each vehicle, battery chemical characteristics, off-site time, and total available power of the grid are used as state inputs. The strategy network directly outputs the power allocation ratio of each vehicle. The allocation strategy is continuously optimized by combining offline training with online small-step fine-tuning using historical charging data. As a supplementary implementation to the aforementioned multi-dimensional feature fusion evaluation model, it can also achieve differentiated and dynamic power allocation effects.

[0056] In another implementation, the aforementioned dynamic power demand assessment, flexible routing control, and active shaping algorithms may not be fully deployed within the edge computing master node of a single charging pile. Instead, the computationally intensive multi-dimensional feature assessment and weight calculation are moved to the cloud scheduling platform for centralized processing. The cloud calculates the power allocation scheme based on the overall load of multiple charging piles in the region and the grid scheduling information, and then sends the allocation results to the local edge controllers of each charging pile to perform duty cycle adjustment and staggered phase shift control. This cloud-edge collaborative architecture, while retaining the core allocation logic and seamless switching and active shaping control methods of this invention, can further support regional-level energy supply collaborative optimization across charging piles and sites.

[0057] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, any modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope defined by the claims of the present invention.

Claims

1. A power supply method for an electric vehicle charging device, applied to a charging pile including a shared power pool, a master control node, and multiple charging ports, wherein the shared power pool includes multiple sets of power modules connected to the multiple charging ports via a power bus, characterized in that, include: The battery status parameters of each vehicle connected to the charging pile and the user-preset departure time are obtained. The battery status parameters include real-time state of charge, battery capacity, upper limit of charging rate, upper limit of charging voltage, and upper limit of charging current. Based on the battery state parameters and the departure time, the charging urgency parameters and power upper limit values ​​of each vehicle being charged are calculated. Based on the charging urgency parameter and the real-time state of charge, the normalized fairness demand weight of each vehicle charging is calculated, and the sum of the fairness demand weights of each vehicle charging is 1. The initial allocation of power to each charging vehicle is obtained by first allocating the total power according to the fairness demand weight. The remaining power corresponding to the weight share that has not been exhausted due to reaching the power limit is iteratively redistributed in the set of charging vehicles that are not yet saturated according to the fairness demand weight ratio until the remaining power is less than the preset threshold, thus obtaining the allocation of power to each charging vehicle. The power allocation of each charging vehicle is combined with the charging voltage of the corresponding charging vehicle to convert it into the target duty cycle of the corresponding power module. The actual output duty cycle of the power module is controlled to be adjusted step by step towards the target duty cycle according to a preset single-step increment, so that the output power of the power module smoothly transitions to the allocated power, and the established charging handshake session is not interrupted during the adjustment process. Each power module involved in the output is assigned a different switching phase offset angle, the switching phase offset angle being according to... The calculation yielded, where Number the power module. To determine the total number of power modules participating in this output, each power module is controlled to turn on and off sequentially according to its respective switching phase offset angle.

2. The power supply method for an electric vehicle charging device according to claim 1, characterized in that, The charging urgency parameter is calculated by multiplying the difference between the target state of charge and the real-time state of charge of the vehicle being charged by the battery capacity, and then dividing by the remaining time before departure. The remaining time before departure is the difference between the user-preset departure time and the current system time.

3. The power supply method for an electric vehicle charging device according to claim 1, characterized in that, The power upper limit is calculated by comparing the product of the charging rate upper limit and the battery capacity, and the product of the charging voltage upper limit and the charging current upper limit, and taking the smaller value as the corresponding power upper limit for the vehicle being charged.

4. The power supply method for an electric vehicle charging device according to claim 1, characterized in that, The fairness requirement weight is calculated as follows: the sum of the charging urgency parameter of each charging vehicle and the reciprocal of the corresponding real-time state of charge is normalized to obtain the fairness requirement weight of each charging vehicle. When the real-time state of charge is zero, a preset minimum positive number is used to replace the real-time state of charge for the reciprocal calculation.

5. The power supply method for an electric vehicle charging device according to claim 1, characterized in that, The method for calculating the allocated power is as follows: the total power is initially allocated according to the fairness demand weight to obtain the initial allocated power of each charging vehicle. The difference between the total power and the sum of the initial allocated power of each charging vehicle is taken as the remaining power. Within the set of charging vehicles that have not reached the power upper limit, the remaining power is redistributed according to the proportion of the fairness demand weight. The redistribution process is repeated until the remaining power is less than a preset threshold to obtain the allocated power of each charging vehicle.

6. The power supply method for an electric vehicle charging device according to claim 1, characterized in that, Also includes: When the power source of a charging port is switched from the original power module to another idle power module, the output duty cycle of the other idle power module is controlled to gradually increase from zero according to the preset single-step increment to take over the load. At the same time, the output duty cycle of the original power module is controlled to decrease synchronously at the same rate, so that the current output by the charging port remains continuous.

7. The power supply method for an electric vehicle charging device according to claim 1, characterized in that, During the step adjustment of the actual output duty cycle of the power module, the output current and output voltage feedback values ​​of the power module are collected in real time. The duty cycle command is corrected by proportional-integral adjustment so that the actual output power of the power module tracks the power allocated to the vehicle being charged.

8. The power supply method for an electric vehicle charging device according to claim 1, characterized in that, Also includes: The system obtains the power upper limit instruction issued by the power grid dispatch center, determines whether the sum of the allocated power of each charging vehicle exceeds the power upper limit instruction, and if it does, uses the ratio of the power upper limit instruction to the sum of the allocated power as a scaling factor. The scaling factor is less than 1. The scaling factor is multiplied by the allocated power of each charging vehicle to obtain the execution power instruction for the corresponding charging vehicle, and the corresponding power module is controlled to output according to the execution power instruction.

9. The power supply method for an electric vehicle charging device according to claim 1, characterized in that, It also includes: real-time monitoring of the current imbalance on the three-phase input side; when the difference between the maximum and minimum phase currents in the three-phase current is detected to exceed the preset imbalance threshold, the connection ratio of each power module on the three-phase input side is adjusted to make the three-phase load more balanced.

10. An electric vehicle charging device, characterized in that, The device includes a shared power pool, a master control node, multiple charging ports, and a communication interface. The shared power pool includes multiple power modules connected to the multiple charging ports via a power bus. The communication interface is used to collect messages sent by the battery management system of the vehicle connected to each charging port. The master control node is connected to the shared power pool and the communication interface, and is used to execute the power supply method of the electric vehicle charging device according to any one of claims 1 to 9.

Images