CN115800332B

CN115800332B - Load adjusting method and system

Info

Publication number: CN115800332B
Application number: CN202310024086.0A
Authority: CN
Inventors: 王利强; 范杨平
Original assignee: Xian Linchr New Energy Technology Co Ltd
Current assignee: Xian Linchr New Energy Technology Co Ltd
Priority date: 2023-01-09
Filing date: 2023-01-09
Publication date: 2023-05-23
Anticipated expiration: 2043-01-09
Also published as: CN115800332A

Abstract

The application provides a load adjusting method and system, and relates to the technical field of power electronics. The power current of each phase of the three phases corresponding to the preset alternating current bus is obtained, the current adjustment quantity of each phase is calculated according to the power current of each phase, the target current adjustment quantity of each phase of each three-phase conversion device in at least one three-phase conversion device to be scheduled is determined according to the current adjustment quantity of each phase, and the target current adjustment quantity of each phase is sent to each three-phase conversion device, so that each three-phase conversion device respectively adjusts the load of each phase on the preset alternating current bus according to the target current adjustment quantity of each phase, electric energy transfer between phase lines is realized, load balance of three phases is guaranteed, and normal electricity consumption needs are not required to be restrained.

Description

Load adjusting method and system

Technical Field

The application relates to the technical field of power electronics, in particular to a load adjusting method and a system.

Background

With the continuous popularization of electric vehicles, the charging power requirement is larger and larger, and the requirement performance in an industrial park or a district is obvious. The charging device and the resident electric equipment strive for the electric charge of the power grid because the charging power is high and the charging time period of the charging device and the resident electric equipment are overlapped, wherein the three-phase load and the single-phase load in the device can cause one phase or two phases in the three-phase power grid to generate load pressure.

In the prior art, in order to relieve the load pressure of a phase line, the three-phase load and the single-phase load can be charged in a time-sharing manner, a priority order is set, the power of the load on the phase line generating the load pressure can be reduced, and when the load pressure is smaller, the normal power consumption of the load is recovered.

Disclosure of Invention

The invention aims to provide a load adjusting method and a system for solving the technical problem that the load adjustment needs to restrain the normal electricity consumption requirement in the prior art.

In order to achieve the above purpose, the technical solution adopted in the embodiment of the present application is as follows:

in a first aspect, embodiments of the present application provide a load adjustment method, including:

acquiring power currents of each phase of three phases corresponding to a preset alternating current bus;

calculating the current adjustment quantity of each phase according to the power current of each phase;

according to the current adjustment quantity of each phase, respectively determining a target current adjustment quantity of each three-phase conversion device in the phases of at least one three-phase conversion device to be scheduled;

And sending the target current adjustment quantity of each phase to each three-phase conversion device, so that each three-phase conversion device respectively adjusts the load of each phase on the preset alternating current bus according to the target current adjustment quantity of each phase.

Optionally, the power current includes: and calculating the current adjustment quantity of each phase according to the power current of each phase, wherein the current adjustment quantity comprises the following steps:

according to the active currents of the phases, respectively calculating the active current adjustment quantity of each phase;

according to the reactive current of each phase, determining the reactive current adjustment quantity of each phase;

the method for respectively determining the target current adjustment quantity of each three-phase conversion device in the three-phase conversion devices to be scheduled according to the current adjustment quantity of each phase comprises the following steps:

according to the active current adjustment quantity of each phase, respectively determining a target active current adjustment quantity of each three-phase conversion device in each phase in at least one three-phase conversion device to be scheduled;

determining target reactive current adjustment amounts of each three-phase transformation equipment in each phase according to the reactive current adjustment amounts of each phase;

Said transmitting the target current adjustment amounts of the respective phases to said each three-phase conversion device includes:

and sending the target active current adjustment quantity and the target reactive current adjustment quantity of each phase to each three-phase conversion device.

Optionally, if the number of the three-phase transformation devices is at least one, determining, according to the active current adjustment amounts of the phases, a target active current adjustment amount of each three-phase transformation device in the phases of each three-phase transformation device to be scheduled, respectively, including:

respectively determining active scheduling coefficients corresponding to each three-phase conversion device according to the schedulable active capacity of at least one three-phase conversion device;

and respectively determining the target active current adjustment quantity of each three-phase transformation equipment in each phase according to the active current adjustment quantity of each phase and the active scheduling coefficient corresponding to each three-phase transformation equipment in the at least one three-phase transformation equipment.

Optionally, if the number of the three-phase transformation devices is at least one, the determining, according to the reactive current adjustment amounts of the respective phases, the target reactive current adjustment amount of each three-phase transformation device in the respective phases includes:

According to the schedulable reactive capacity of at least one three-phase conversion device, determining reactive power scheduling coefficients corresponding to each three-phase conversion device respectively;

and respectively determining the target reactive current adjustment quantity of each three-phase transformation equipment in each phase according to the reactive current adjustment quantity of each phase and the reactive power dispatching coefficient corresponding to each three-phase transformation equipment.

Optionally, the active current of each phase is the active current of each phase at the power grid side; the step of calculating the active current adjustment quantity of each phase according to the active current of each phase comprises the following steps:

calculating a first average active current according to the active currents of the phases;

and according to the first average active current and the active current of each phase, respectively calculating the active current adjustment quantity of each phase by adopting a preset active current loop control algorithm.

Optionally, the reactive current of each phase is the reactive current of each phase at the power grid side; and respectively determining reactive current adjustment amounts of the phases according to the reactive currents of the phases, wherein the reactive current adjustment amounts comprise:

and according to the reactive current of each phase and a preset reference reactive current value, adopting a preset reactive current loop control algorithm to respectively calculate reactive current adjustment quantity of each phase.

Optionally, the active current of each phase is the active current of each phase at the load side; the step of calculating the active current adjustment quantity of each phase according to the active current of each phase comprises the following steps:

calculating a second average active current according to the active currents of the phases;

and obtaining the active current adjustment quantity of each phase according to the difference value of the active current of each phase and the second average active current.

Optionally, the reactive current of each phase is a reactive current of each phase at a load side; and respectively determining reactive current adjustment amounts of the phases according to the reactive currents of the phases, wherein the reactive current adjustment amounts comprise:

and determining the reactive current of each phase as the reactive current adjustment quantity of each phase.

Optionally, the obtaining the power current of each phase of the three phases corresponding to the preset ac bus includes:

detecting the current of the three phases and the voltage of the three phases corresponding to the preset alternating current bus;

and respectively determining the active current of each phase and the reactive current of each phase according to the current of the three phases and the voltage of the three phases.

Acquiring the power of each three-phase conversion device and power factor information;

and determining the active current of each phase and the reactive current of each phase according to the power of each three-phase conversion device, the power factor information of each three-phase conversion device and the voltage of a preset alternating current power supply.

In a second aspect, embodiments of the present application provide a load adjustment system, including: the device comprises a transformer, at least one three-phase conversion device, a control device and a load;

the transformer is used for being electrically connected with a preset alternating current bus, the at least one three-phase conversion device is used for being electrically connected with the preset alternating current bus, the load is used for being electrically connected with the preset alternating current bus, the control device is in communication connection with a control unit of each three-phase conversion device, the control device is electrically connected with an outgoing line of the transformer, the control device is further electrically connected with an incoming line of the load, and the control device is used for executing the load adjusting method of the first aspect.

Compared with the prior art, the application has the following beneficial effects:

according to the load adjusting method and system, power currents of the preset alternating current buses corresponding to all phases are obtained, current adjusting amounts of all phases are calculated according to the power currents of all phases, target current adjusting amounts of all phases of each three-phase conversion device in at least one three-phase conversion device to be scheduled are determined according to the current adjusting amounts of all phases, the target current adjusting amounts of all phases are sent to each three-phase conversion device, so that each three-phase conversion device can respectively adjust loads of all phases on the preset alternating current buses according to the target current adjusting amounts of all phases, electric energy transfer between phase lines is achieved, load balance of three phases is guaranteed, and normal electricity consumption needs are not required to be restrained.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural diagram of a load adjustment system according to an embodiment of the present application;

fig. 2 is a schematic flow chart of a load adjustment method according to an embodiment of the present application;

FIG. 3 is a schematic flow chart of another load adjustment method according to an embodiment of the present disclosure;

FIG. 4 is a schematic flow chart of another load adjustment method according to an embodiment of the present disclosure;

FIG. 5 is a schematic flow chart of another load adjustment method according to an embodiment of the present disclosure;

FIG. 6 is a schematic flow chart of another load adjustment method according to an embodiment of the present disclosure;

FIG. 7 is a schematic flow chart of another load adjustment method according to an embodiment of the present disclosure;

FIG. 8 is a schematic flow chart of another load adjustment method according to an embodiment of the present disclosure;

FIG. 9 is a schematic flow chart of another load adjustment method according to an embodiment of the present disclosure;

fig. 10 is a schematic diagram of a load adjusting device according to an embodiment of the present disclosure;

fig. 11 is a schematic diagram of a control device according to an embodiment of the present application.

Detailed Description

For the purposes of making the objects, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments. The components of the embodiments of the present application, which are generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present application, as provided in the accompanying drawings, is not intended to limit the scope of the application, as claimed, but is merely representative of selected embodiments of the application. All other embodiments, based on the embodiments herein, which would be apparent to one of ordinary skill in the art without making any inventive effort, are intended to be within the scope of the present application.

In the description of the present invention, the terms "first," "second," and the like, if any, are used solely for distinguishing between descriptions and not necessarily for indicating or implying a relative importance.

It should be noted that the features of the embodiments of the present invention may be combined with each other without conflict.

After the transformer is led in, a plurality of loads are connected to the three-phase four-wire, and the single-phase load and the three-phase load can be divided into a single-phase power taking single-phase load and a three-phase power taking three-phase load according to a power taking mode of the loads. The single-phase electricity taking mode, such as residential electricity or charging piles and the like, any single-phase load can be connected with one of any three phases and a zero line, and the load is relatively flexible and changeable, so that even if all three-phase loads meet the total amount of electricity loads, the load currents of all phases on the corresponding three phases are generally different, namely the charges in the three phases are uneven and unbalanced; the three-phase power taking mode, such as a three-phase load, generally controls the three-phase currents to be equal symmetrically, but the three-phase currents are not equal, so that unbalance of charges in the three phases may be caused. When a single-phase load and a three-phase load exist on three-phase four lines simultaneously, the charge in the three phases is in an unbalanced condition as a whole.

In the prior art, load adjustment in three phases is performed by setting a priority order of loads and limiting electricity consumption, and in order to adjust the loads of the three phases on the basis of not inhibiting the normal electricity consumption requirement so as to balance charges in the three phases, a load adjustment system is provided. Fig. 1 is a schematic structural diagram of a load adjustment system according to an embodiment of the present application. As shown in fig. 1, the system includes: a transformer 100, at least one three-phase transforming device 300, a control apparatus 400, a load 500.

The transformer 100 is used for electrically connecting a preset ac bus 200, and the transformer 100 can transmit current and voltage to the preset ac bus 200, wherein the preset ac bus 200 is three-phase four-wire, and the last wire is zero wire.

The load 500 is electrically connected to the preset ac bus 200, and provides electric energy to the load 500 through the preset ac bus 200, so that the load 500 can work normally. All loads 500 may be classified into a-phase load (load a in fig. 1), B-phase load (load B in fig. 1), C-phase load (load C in fig. 1) from the perspective of three phases, and the total current of the loads 500 may be classified into IALs, IBLs, and ICLs.

The at least one three-phase conversion device 300 is used for electrically connecting the preset alternating current bus 200, and the at least one three-phase conversion device 300 can transfer the electric energy of the phase lines with less load to the phase lines with heavier load when the load phase difference of the three phases is larger under the condition of meeting the total load requirement, so that the electric energy transfer and the load balance between the phase lines are realized, and the three phases are always in the load balance state.

At least one three-phase transformation device 300 is a composite charging device which is distributed in each geographical area and can be independently operated, can be charged and can be discharged into three-phase lines, and can be discharged into a device to be charged, which is connected with the three-phase transformation device 300. Each three-phase conversion device 300 has the ability to independently regulate reactive and active power, and can be charged or discharged normally.

Alternatively, the at least one three-phase transformation device 300 may be a charging stake or the like.

Alternatively, each three-phase transformation device 300 needs to set aside capacity for energy transfer and reactive current adjustment between three phases based on the original power balance, and then three-phase incoming line current can guarantee three-phase load balance and reactive power to be approximately 0.

For example, the three-phase conversion device 300 may be a three-phase four-wire AC/DC topology structure, such as a three-phase four-leg, a three-phase split capacitor midpoint, etc., which may be used as a topology scheme of the three-phase conversion device 300, and of course, may be other devices with the capability of independently adjusting reactive power and active power, which is not particularly limited in the embodiments of the present application.

After the n three-phase transformation devices 300 are input, the currents of the three-phase transformation devices 300 may be IA1, IB1, IC1 to IAn, IBn, ICn, respectively. In the embodiment of the present application, when the sum of the current of the three-phase transformation device 300 and the current of the load is approximately the same in real time and the reactive components cancel, the three-phase active current balance and the reactive current of the three-phase incoming current can be made to be approximately 0.

The control device 400 is in communication connection with each three-phase transformation device 300, specifically, the control device 400 is in communication connection with a control unit of each three-phase transformation device 300, so that the control unit of the control device 400 can send a control instruction to each three-phase transformation device 300, so that each three-phase transformation device 300 can perform current adjustment of each phase in three phases according to the control instruction, specifically, active current and reactive current adjustment of each phase can be performed, and further electric energy transfer and load balance between phase lines are achieved.

The control device 400 is electrically connected to an outgoing line of the transformer 100, and the control device 400 is further electrically connected to an incoming line of the load 500, so as to calculate a current adjustment amount of the three-phase transformation device 300 according to a current at the outgoing line of the transformer 100, specifically, an adjustment amount of active current and reactive current, or calculate a current adjustment amount of the three-phase transformation device 300 according to a current at the incoming line of the load 500, so as to control the three-phase transformation device 300 according to the adjustment amount to realize electric energy transfer and load balance.

Alternatively, the control device 400 may be connected to an outlet of the transformer 100 through a current sensor to detect and obtain a current at the outlet of the transformer 100, and the control device 400 may be connected to an inlet of the load 500 through the current sensor to detect and obtain a current at the inlet of the load 500.

The application provides a load regulation system, includes: the transformer is used for being electrically connected with a preset alternating current bus, the at least one three-phase conversion device is used for being electrically connected with the preset alternating current bus, the load is used for being electrically connected with the preset alternating current bus, the control device is in communication connection with a control unit of each three-phase conversion device, the control device is electrically connected with an outgoing line of the transformer, the control device is further electrically connected with an incoming line of the load, and according to collected current information, the control device further controls the three-phase conversion device to conduct current adjustment of each of three phases, specifically, active current and reactive current adjustment can be conducted, and then electric energy transfer and load balance between phase lines are achieved.

In order to achieve power transfer and load balancing between phase lines based on the embodiment of the load adjusting system described in fig. 1, in the solution of the present application, a load adjusting method is provided, and by way of specific example, a load adjusting method provided in the embodiment of the present application is explained below. Fig. 2 is a schematic flow chart of a load adjustment method according to an embodiment of the present application. As shown in fig. 2, the method includes:

s201, obtaining power currents of each phase of three phases corresponding to a preset alternating current bus.

Because the three phases in the preset alternating current bus are required to be regulated, the power current of each phase in the corresponding three phases of the preset alternating current bus is required to be acquired first, and the regulation quantity is determined according to the acquired current power current and then the regulation can be carried out through the three-phase conversion equipment.

S202, calculating current adjustment amounts of the phases according to the power currents of the phases.

When the power currents of the corresponding three phases of the preset alternating current buses are unbalanced, the power currents of all the phases need to be adjusted respectively, so that the current adjustment quantity of each phase can be calculated according to the power currents of all the phases, and the power currents of the three phases can be adjusted according to the current adjustment quantity of each phase through the three-phase conversion equipment.

S203, respectively determining the target current adjustment quantity of each three-phase transformation device in each phase in at least one three-phase transformation device to be scheduled according to the current adjustment quantity of each phase.

The load regulation system comprises at least one three-phase conversion device, and the at least one three-phase conversion device which can accept the schedule is determined by carrying out communication inquiry or uploading the running state (accepting the schedule or not accepting the schedule) of each three-phase conversion device in real time. The three-phase conversion device that is acceptable for scheduling is understood to be a three-phase conversion device that can be load-regulated at this time.

If the number of the three-phase transformation devices to be scheduled is one, the current adjustment quantity of each phase is the target current adjustment quantity of the three-phase transformation device in each phase. I.e. a percentage of the current regulation is distributed to the one three-phase conversion device, and if the regulation demand is greater than the regulation capacity of the one three-phase conversion device, the regulation is performed according to the regulation capacity of the one three-phase conversion device.

If the number of the three-phase transformation devices to be scheduled is multiple, determining a target current adjustment amount of each of the multiple three-phase transformation devices according to the current adjustment amounts of each phase so as to perform load adjustment jointly through the multiple three-phase transformation devices.

And S204, sending target current adjustment amounts of all phases to each three-phase conversion device, so that each three-phase conversion device respectively adjusts the load of each phase on a preset alternating current bus according to the target current adjustment amounts of all the phases.

After each three-phase conversion device receives the target current adjustment quantity, each three-phase conversion device respectively adjusts the load of each phase on the preset alternating current bus according to the target current adjustment quantity of each phase.

Specifically, each three-phase conversion device adds an adjustment amount on the basis of original electricity consumption according to the target current adjustment amount of each phase, and the output current of each three-phase conversion device to the corresponding three phases of the preset alternating current bus or the amount of the received current can be determined.

Optionally, the state of each three-phase transformation device is processed according to the respective settings and actual state according to the following principles: if the current operation capacity of a certain three-phase conversion device plus the adjustment quantity is converted into the total current or apparent power which is smaller than or equal to the total capacity of the three-phase conversion device, the adjustment quantity is directly added on the basis of the original operation. If the current running capacity of a certain three-phase conversion device plus the adjustment quantity is converted into total current or apparent power which is larger than or equal to the total capacity, the adjustment quantity is preferentially satisfied, and the rest part outside the adjustment quantity in the total capacity is the used capacity of the three-phase conversion device. That is, when the load is adjusted according to the current adjustment amount, the current operating capacity, such as the charging power demand of the three-phase conversion device, may be sacrificed.

Optionally, if the capacity that all three-phase transformation devices currently running can schedule is smaller than the adjustment amount for adjusting the three-phase imbalance, when the three-phase imbalance reaches the warning threshold, the active current limit will be issued forcedly, and the load constraint principle is executed.

Optionally, the current of one phase of the three phases corresponding to the preset ac bus may be obtained, and the target current adjustment amount of the one phase may be obtained by calculation, and each three-phase transformation device may adjust the load of each phase on the preset ac bus according to the target current adjustment amount of the one phase. During adjustment, the target current adjustment amount of each phase is the same, and can be the target current adjustment amount of the one phase.

According to the load adjusting method, the power current of each phase of the preset alternating current bus corresponding to the three phases is obtained, the current adjusting quantity of each phase is calculated according to the power current of each phase, the target current adjusting quantity of each phase of each three-phase conversion device in at least one three-phase conversion device to be scheduled is determined according to the current adjusting quantity of each phase, the target current adjusting quantity of each phase is sent to each three-phase conversion device, each three-phase conversion device is enabled to respectively adjust the load of each phase on the preset alternating current bus according to the target current adjusting quantity of each phase, electric energy transfer between phase lines is achieved, load balance of three phases is guaranteed, and normal electricity consumption needs are not needed to be restrained.

On the basis of the load regulation method shown in fig. 2, the embodiment of the application also provides another implementation method of the load regulation method. Optionally, fig. 3 is a schematic flow chart of another load adjustment method provided in an embodiment of the present application, as shown in fig. 3, where the power current includes: active current, which is current generated by the operation of a load, and reactive current, which depends on load characteristics or control performance of the three-phase conversion device. When the sinusoidal current and the sinusoidal voltage have a phase difference, the sin value corresponding to the phase difference is a reactive component, and the cos value corresponding to the phase difference is an active component.

The active current of each phase and the reactive current of each phase in the three phases corresponding to the preset alternating current bus can be the current of the incoming line side or the outgoing line side of the preset alternating current bus, and the like.

The method S202 calculates the current adjustment amount of each phase according to the power current of each phase, including:

s301, calculating the active current adjustment quantity of each phase according to the active current of each phase.

Specifically, according to the active currents of the three phases (A phase, B phase and C phase) and the active current of the A phase, the active current adjustment quantity of the A phase can be calculated, namely the active adjustment of the A phase in the preset alternating current bus is needed.

According to the active current of the three phases (A phase, B phase and C phase) and the active current of the B phase, the active current adjustment quantity of the B phase can be calculated, namely the active adjustment of the B phase line in the preset alternating current bus is needed.

According to the active current of the three phases (A phase, B phase and C phase) and the active current of the C phase, the active current adjustment quantity of the C phase can be calculated, namely the active adjustment of the C phase line in the preset alternating current bus is needed.

S302, according to reactive currents of all phases, determining reactive current adjustment amounts of all phases respectively.

And determining the reactive current adjustment quantity of the phase A according to the reactive current of the phase A, namely, the reactive current adjustment of the phase A in the preset alternating current bus is required.

And determining the reactive current adjustment quantity of the B phase according to the reactive current of the B phase, namely, the reactive current adjustment of the B phase in the preset alternating current bus is required.

And determining the reactive current adjustment quantity of the C phase according to the reactive current of the C phase, namely, the reactive current adjustment of the C phase in a preset alternating current bus is required.

The method S203 determines, according to the current adjustment amounts of the phases, a target current adjustment amount of each three-phase conversion device in each phase of at least one three-phase conversion device to be scheduled, including:

s303, according to the active current adjustment quantity of each phase, respectively determining the target active current adjustment quantity of each three-phase conversion device in each phase in at least one three-phase conversion device to be scheduled.

The at least one three-phase transformation device performs active adjustment on three phases in the preset alternating current bus together, so that the target active current adjustment quantity of each three-phase transformation device in each phase in the at least one three-phase transformation device to be scheduled is determined according to the active current adjustment quantity.

If the number of the three-phase transformation devices to be scheduled is one, the active current adjustment quantity of each phase is the target active current adjustment quantity of the three-phase transformation device in each phase. I.e. the percentage of active current adjustment is distributed to the one three-phase transformation device, and is adjusted according to the adjustment capability of the one three-phase transformation device if the active current adjustment requirement is greater than the adjustment capability of the one three-phase transformation device.

S304, determining the target reactive current adjustment quantity of each three-phase transformation device in each phase according to the reactive current adjustment quantity of each phase.

The at least one three-phase conversion device also jointly performs reactive power regulation on three phases in the preset alternating current bus, so that a target reactive current regulation quantity of each three-phase conversion device in each phase in the at least one three-phase conversion device to be scheduled is determined according to the reactive current regulation quantity.

And if the number of the three-phase conversion equipment to be scheduled is one, the reactive current adjustment quantity of each phase is the target reactive current adjustment quantity of the three-phase conversion equipment in each phase. I.e. the percentage of reactive current regulation is distributed to the one three-phase transformation device, and if the reactive current regulation demand is greater than the regulation capacity of the one three-phase transformation device, the regulation is performed according to the regulation capacity of the one three-phase transformation device.

The above-described method S204 of transmitting the target current adjustment amount of each phase to each three-phase conversion apparatus includes:

and S305, transmitting the target active current adjustment quantity and the target reactive current adjustment quantity of each phase to each three-phase conversion device.

After each three-phase conversion device receives the current adjustment quantity, each three-phase conversion device respectively adjusts the load of each phase on the preset alternating current bus according to the target active current adjustment quantity and the target reactive current adjustment quantity of each phase.

Optionally, the active current and the reactive current of one phase of the three phases corresponding to the preset ac bus can be obtained, the target active current adjustment quantity and the target reactive current adjustment quantity of the one phase are obtained through calculation, and each three-phase conversion device adjusts the load of each phase on the preset ac bus according to the target active current adjustment quantity and the target reactive current adjustment quantity of the one phase. During adjustment, the target active current adjustment quantity and the target reactive current adjustment quantity of each phase are the same, and can be the target active current adjustment quantity and the target reactive current adjustment quantity of the phase.

According to the load adjusting method, active currents of all phases and reactive currents of all phases in the corresponding three phases of the preset alternating current bus are obtained, active current adjusting amounts of all phases are calculated according to the active currents of the three phases and the active currents of all phases, reactive current adjusting amounts of all phases are determined according to the reactive currents of all phases, target active current adjusting amounts of all phases of each three-phase conversion device in at least one three-phase conversion device to be scheduled are determined according to the active current adjusting amounts of all phases, target reactive current adjusting amounts of all phases of each three-phase conversion device are determined according to the reactive current adjusting amounts of all phases, target active current adjusting amounts and target reactive current adjusting amounts of all phases are sent to each three-phase conversion device, so that loads of all phases on the preset alternating current bus are adjusted according to the target active current adjusting amounts and the target reactive current adjusting amounts of all phases respectively, and active current adjusting of all phases are achieved.

On the basis of the load regulation method shown in fig. 3, the embodiment of the application also provides another implementation method of the load regulation method. Optionally, fig. 4 is a schematic flow chart of another load adjustment method provided in the embodiment of the present application, as shown in fig. 4, if the number of three-phase conversion devices is at least one, in the method S303, a target active current adjustment amount of each three-phase conversion device in each phase of at least one three-phase conversion device to be scheduled is determined according to the active current adjustment amounts of each phase, including:

s401, respectively determining the active scheduling coefficients corresponding to each three-phase conversion device according to the schedulable active capacity of at least one three-phase conversion device.

And obtaining the reported schedulable active capacity reported by at least one three-phase conversion device, multiplying a constant smaller than 1 on the basis of the reported schedulable active capacity to obtain the schedulable active capacity of each three-phase conversion device, and ensuring the reliability of the schedulable active capacity.

Calculating the schedulable total active capacity according to the schedulable active capacity of each three-phase transformation device in the at least one three-phase transformation device, and calculating the active scheduling coefficient of each three-phase transformation device according to the schedulable total active capacity and the schedulable active capacity of each three-phase transformation device.

Specifically, the proportion of the schedulable active capacity of each three-phase transformation device in the schedulable total active capacity (the schedulable active capacity of each three-phase transformation device divided by the schedulable total active capacity) is the active scheduling coefficient of each three-phase transformation device.

If the number of the three-phase conversion devices is one, the active scheduling coefficient is 1.

S402, according to the active current adjustment quantity of each phase and the active scheduling coefficient corresponding to each three-phase conversion device in at least one three-phase conversion device, respectively determining the target active current adjustment quantity of each three-phase conversion device in each phase.

Specifically, the active scheduling coefficient corresponding to each three-phase transformation device is multiplied by the active current adjustment quantity of each phase, so that the target active current adjustment quantity of each three-phase transformation device in each phase can be obtained.

If the number of the three-phase conversion devices is one, the active scheduling coefficient is 1, and at this time, the active current adjustment quantity of each phase is the target active current adjustment quantity of the three-phase conversion device in each phase.

According to the load adjusting method provided by the embodiment of the application, if the number of the three-phase transformation devices is at least one, the active dispatching coefficients corresponding to each three-phase transformation device are respectively determined according to the schedulable active capacity of the at least one three-phase transformation device, and the target active current adjusting quantity of each three-phase transformation device in each phase is respectively determined according to the active current adjusting quantity of each phase and the active dispatching coefficients corresponding to each three-phase transformation device in the at least one three-phase transformation device, so that each three-phase transformation device can realize active current balance according to the target active current adjusting quantity.

On the basis of the load regulation method shown in fig. 3, the embodiment of the application also provides another implementation method of the load regulation method. Optionally, fig. 5 is a schematic flow chart of another load adjustment method provided in the embodiment of the present application, as shown in fig. 5, if the number of three-phase transformation devices is at least one, in the method S304, determining, according to the reactive current adjustment amounts of each phase, a target reactive current adjustment amount of each three-phase transformation device in each phase, including:

s501, respectively determining reactive power dispatching coefficients corresponding to each three-phase transformation equipment according to the dispatchable reactive power capacity of at least one three-phase transformation equipment.

And acquiring the reported schedulable reactive capacity reported by at least one three-phase conversion device, multiplying a constant smaller than 1 on the basis of the reported schedulable reactive capacity to obtain the schedulable reactive capacity of each three-phase conversion device, and ensuring the reliability of the schedulable reactive capacity.

Calculating the schedulable total reactive capacity according to the schedulable reactive capacity of each three-phase conversion device in the at least one three-phase conversion device, and calculating the reactive power scheduling coefficient of each three-phase conversion device according to the schedulable total reactive capacity and the schedulable reactive capacity of each three-phase conversion device.

Specifically, the proportion of the schedulable reactive capacity of each three-phase transformation device in the schedulable total reactive capacity (the schedulable reactive capacity of each three-phase transformation device divided by the schedulable total reactive capacity) is the reactive power scheduling coefficient of each three-phase transformation device.

If the number of the three-phase conversion devices is one, the reactive power dispatching coefficient is 1.

S502, according to reactive current adjustment amounts of all phases and reactive power dispatching coefficients corresponding to all three-phase transformation devices, determining target reactive current adjustment amounts of all three-phase transformation devices in all phases respectively.

Specifically, the reactive power dispatching coefficient corresponding to each three-phase transformation device is multiplied by the reactive power current adjustment quantity of each phase, so that the target reactive power current adjustment quantity of each three-phase transformation device in each phase can be obtained.

If the number of the three-phase conversion devices is one, the reactive power dispatching coefficient is 1, and at this time, the reactive current adjustment quantity of each phase is the target reactive current adjustment quantity of the three-phase conversion device in each phase.

According to the load adjusting method provided by the embodiment of the application, if the number of the three-phase transformation devices is at least one, the reactive power dispatching coefficient corresponding to each three-phase transformation device is respectively determined according to the schedulable reactive power capacity of at least one three-phase transformation device, and the target reactive power current adjusting quantity of each three-phase transformation device in each phase is respectively determined according to the reactive power current adjusting quantity of each phase and the reactive power dispatching coefficient corresponding to each three-phase transformation device, so that each three-phase transformation device can realize reactive power components near zero according to the reactive power active current adjusting quantity.

On the basis of the load regulation method shown in fig. 3, the embodiment of the application also provides another implementation method of the load regulation method. Optionally, fig. 6 is a schematic flow chart of another load adjustment method provided in the embodiment of the present application, as shown in fig. 6, when active currents of each phase are active currents (IA, IB, IC side) of each phase on the grid side, in the method S301, active current adjustment amounts of each phase are calculated according to the active currents of each phase, including:

s601, calculating a first average active current according to the active currents of the phases.

And averaging the three-phase active currents to obtain a first average active current.

S602, according to the first average active current and the active current of each phase, respectively calculating the active current adjustment quantity of each phase by adopting a preset active current loop control algorithm.

Specifically, the first average active current and the phase A (or the phase B or the phase C) are input into a preset active current loop control algorithm, and the active current adjustment quantity of the phase A (or the phase B or the phase C) can be obtained.

The preset active current loop control algorithm may be a PI control algorithm, the PI control algorithm is limited by amplitude, the first average active current is used as a target value, the active currents of each phase are used as input information, and the PI control algorithm may output a corresponding adjustment value. The magnitude and direction of the adjustment amount represent the active ingredient and the magnitude.

According to the load adjusting method, when the active currents of all phases are the active currents of all phases on the power grid side, according to the active currents of all phases, a first average active current is calculated, according to the first average active current and the active currents of all phases, a preset active current loop control algorithm is adopted, active current adjusting amounts of all phases are calculated respectively, and then target active current adjusting amounts of all three-phase transformation equipment in all phases can be determined through the active current adjusting amounts of all phases.

On the basis of the load regulation method shown in fig. 3, the embodiment of the application also provides another implementation method of the load regulation method. Optionally, when the reactive current of each phase is the reactive current (IA, IB, IC side) of each phase on the grid side, the method S302 determines, according to the reactive current of each phase, the reactive current adjustment amount of each phase, respectively, including:

Specifically, the preset reference reactive current value and the phase A (or the phase B or the phase C) are input into a preset reactive current loop control algorithm, and the reactive current adjustment quantity of the phase A (or the phase B or the phase C) can be obtained.

In the embodiment of the present application, the preset reference reactive current value may be O amperes.

The preset reactive current loop control algorithm can be a PI control algorithm, the preset reference reactive current value is used as a target value through amplitude limitation of the PI control algorithm, reactive current of each phase is used as input information, and the PI control algorithm can output corresponding adjustment quantity. The magnitude and direction of the adjustment amount represent the reactive component and magnitude.

According to the load adjusting method, according to reactive current of each phase and a preset reference reactive current value, a preset reactive current loop control algorithm is adopted to respectively calculate reactive current adjusting amounts of each phase, and then target reactive current adjusting amounts of each three-phase transformation equipment in each phase can be determined through the reactive current adjusting amounts of each phase.

On the basis of the load regulation method shown in fig. 3, the embodiment of the application also provides another implementation method of the load regulation method. Optionally, fig. 7 is a schematic flow chart of another load adjustment method provided in the embodiment of the present application, as shown in fig. 7, when active currents of each phase are active currents of each phase on a load side (IAL, IBL, ICL side), in the method S301, active current adjustment amounts of each phase are calculated according to the active currents of each phase, including:

S701, calculating a second average active current according to the active currents of the phases.

And averaging the three-phase active currents to obtain a second average active current.

S702, obtaining the active current adjustment quantity of each phase according to the difference value between the second average active current and the active current of each phase.

Specifically, the difference between the active current of each phase and the second average active current is used as the active current adjustment amount of each phase.

According to the load adjusting method, when the active current of each phase is the active current of each phase at the load side, the second average active current is calculated according to the active current of each phase, and the active current adjusting quantity of each phase is obtained according to the difference value of the active current of each phase and the second average active current, so that the target active current adjusting quantity of each three-phase conversion device in each phase can be determined according to the active current adjusting quantity of each phase.

On the basis of the load regulation method shown in fig. 3, the embodiment of the application also provides another implementation method of the load regulation method. Optionally, when the active current of each phase is the active current of each phase on the load side (on the IAL, IBL, ICL side), the method S302 determines, according to the reactive current of each phase, the reactive current adjustment amount of each phase, respectively, including:

According to the load adjusting method, reactive currents of all phases are reactive currents of all phases at a load side, the reactive currents of all phases are determined to be reactive current adjusting amounts of all phases, and then target reactive current adjusting amounts of all three-phase transformation equipment at all phases can be determined through the reactive current adjusting amounts of all phases.

On the basis of the load regulation method shown in fig. 3, the embodiment of the application also provides another implementation method of the load regulation method. Optionally, fig. 8 is a schematic flow chart of another load adjustment method provided in the embodiment of the present application, as shown in fig. 8, in the method S201, the obtaining a power current of each of three phases corresponding to a preset ac bus includes:

s801, detecting the current and the voltage of the three phases corresponding to the preset alternating current bus.

Three-phase currents and three-phase voltages on the grid side or the load side of the preset alternating current bus are detected.

S802, determining the active current of each phase and the reactive current of each phase according to the current of the three phases and the voltage of the three phases.

According to the three-phase voltage, the frequency and the phase can be obtained through phase-locked loop processing, and according to the frequency and the phase and the current of each phase in the three phases, the active current of each phase and the reactive current of each phase can be determined through single-phase current detection.

Specifically, the voltage of the phase A can be processed by a phase-locked loop to obtain frequency and phase, wherein the phase is the detection phase of the phase A, and the phase difference of the three phases is 120 degrees, so that the active current of the phase A and the reactive current of the phase A can be obtained through single-phase current detection according to the frequency, the phase and the phase A current; subtracting 120 and B phase currents according to the frequency and the phase, and obtaining B phase active current and B phase reactive current through single-phase current detection; according to the frequency, the phase and 120-phase current are added, and the active current of the C phase and the reactive current of the C phase can be obtained through single-phase current detection.

Optionally, the three-phase voltages can be processed through a phase-locked loop to obtain the frequency and the phase of each phase, wherein the phase of each phase is the detection phase of the A phase, the detection phase of the B phase and the detection phase of the C phase, and then the active current of each phase and the reactive current of each phase can be obtained through single-phase current detection according to the frequency, the phase of each phase and the current of each phase.

According to the load adjusting method, the three-phase current and the three-phase voltage corresponding to the preset alternating current bus are detected, and the active current of each phase and the reactive current of each phase are respectively determined according to the three-phase current and the three-phase voltage, so that the determination of the active current of each phase and the reactive current of each phase under the detection condition is realized.

On the basis of the load regulation method shown in fig. 3, the embodiment of the application also provides another implementation method of the load regulation method. Optionally, fig. 9 is a schematic flow chart of another load adjustment method provided in the embodiment of the present application, as shown in fig. 9, in the method S201, the obtaining a power current of each of three phases corresponding to a preset ac bus includes:

and S901, acquiring the power and power factor information of each three-phase conversion device.

If the system does not detect the current and voltage conditions, before each three-phase conversion device is connected into the system according to the requirements, the power and power factor information (the relation curve of the corresponding relation between the power factor and the voltage) of each three-phase conversion device is provided and uploaded to a control device in the load regulation system, namely, the power and the power factor information of each three-phase conversion device are obtained.

Alternatively, the power factor information may be: the three-phase conversion equipment calculates or measures the curve relation of the power factors of all power sections from 0 to full power under different alternating current network voltages. In particular, when the machine is stopped and connected into an alternating current power grid, the capacitive reactive power of the EMC capacitor is uncontrollable, the capacitive reactive current is in direct proportion to the effective value of the voltage of the power grid, and the voltage relationship of the power grid needs to be considered.

Optionally, if the system has no detection condition, for a local small area, such as a charging station or a district parking lot, each three-phase conversion device can be communicatively networked to upload data values to the control device.

S902, determining active currents of all phases and reactive currents of all phases according to the power of each three-phase conversion device, the power factor information of each three-phase conversion device and the voltage of a preset alternating current power supply.

Each three-phase conversion device comprises a preset alternating current power supply which is connected with a preset alternating current bus.

The power factor corresponding to the voltage can be determined according to the voltage of the preset alternating current power supply and the power factor information of each three-phase conversion device. According to the power factor and the power corresponding to the voltage, the active power (power factor multiplied by power) can be calculated, and then the active current can be calculated according to the active power and the voltage. Thus, the active current of each phase can be determined.

According to the power factor and the power corresponding to the voltage, reactive power ((1-power factor) power) can be calculated, and then reactive current can be calculated according to the reactive power and the voltage. Thus, the reactive current of each phase can be determined.

The power and power factor information of each three-phase conversion device are obtained through communication to replace real-time current detection, so that cost can be saved, but the dynamic adjustment speed is limited by the communication transmission speed, when the communication transmission is slow, the adjustment speed is slow, and when the communication transmission is fast, the adjustment speed is fast.

According to the load adjusting method, the power and the power factor information of each three-phase conversion device are obtained, the active current of each phase and the reactive current of each phase are determined according to the power of each three-phase conversion device, the power factor information of each three-phase conversion device and the voltage of a preset alternating current power supply, and the determination of the active current of each phase and the reactive current of each phase under the condition of no detection is achieved.

The following describes a charging control device, a controller and a storage medium provided by the present application for execution, and specific implementation processes and technical effects thereof are referred to above, which are not described in detail below.

Fig. 10 is a schematic diagram of a load adjustment device according to an embodiment of the present application, as shown in fig. 10, where the load adjustment device includes:

the obtaining module 1001 is configured to obtain power currents of each of three phases corresponding to a preset ac bus.

A calculating module 1002, configured to calculate current adjustment amounts of the phases according to the power currents of the phases, respectively.

A determining module 1003, configured to determine, according to the current adjustment amounts of the phases, a target current adjustment amount of each three-phase transformation device in each phase of the at least one three-phase transformation device to be scheduled.

And a sending module 1004, configured to send the target current adjustment amounts of the phases to each three-phase conversion device, so that each three-phase conversion device respectively adjusts the loads of the phases on the preset ac bus according to the target current adjustment amounts of the phases.

Optionally, the calculating module 1002, specifically for the power current, includes: active current and reactive current, respectively calculating current adjustment amounts of each phase according to the power current of each phase, including: according to the active current of each phase, respectively calculating the active current adjustment quantity of each phase; according to the reactive current of each phase, determining the reactive current adjustment quantity of each phase; according to the current adjustment quantity of each phase, respectively determining the target current adjustment quantity of each three-phase conversion device in each phase in at least one three-phase conversion device to be scheduled, wherein the method comprises the following steps: according to the active current adjustment quantity of each phase, respectively determining the target active current adjustment quantity of each three-phase conversion device in each phase in at least one three-phase conversion device to be scheduled; determining target reactive current adjustment quantity of each three-phase transformation equipment in each phase according to reactive current adjustment quantity of each phase; transmitting a target current adjustment amount for each phase to each three-phase conversion device, comprising: and sending the target active current adjustment quantity and the target reactive current adjustment quantity of each phase to each three-phase conversion device.

Optionally, the determining module 1003 is specifically configured to determine, according to the active current adjustment amounts of the respective phases, the target active current adjustment amounts of each of the at least one three-phase transformation devices to be scheduled in the respective phases if the number of the three-phase transformation devices is at least one, where the determining module includes: according to the schedulable active capacity of at least one three-phase transformation device, respectively determining an active scheduling coefficient corresponding to each three-phase transformation device; and respectively determining the target active current adjustment quantity of each three-phase transformation equipment in each phase according to the active current adjustment quantity of each phase and the active scheduling coefficient corresponding to each three-phase transformation equipment in at least one three-phase transformation equipment.

Optionally, the determining module 1003 is specifically configured to determine, if the number of three-phase transformation devices is at least one, a target reactive current adjustment amount of each three-phase transformation device in each phase according to the reactive current adjustment amount of each phase, where the determining module includes: according to the schedulable reactive capacity of at least one three-phase conversion device, determining reactive power scheduling coefficients corresponding to each three-phase conversion device respectively; and respectively determining the target reactive current regulating quantity of each three-phase transformation equipment in each phase according to the reactive current regulating quantity of each phase and the reactive power dispatching coefficient corresponding to each three-phase transformation equipment.

Optionally, the calculating module 1002 is specifically configured to calculate, according to the active currents of the phases, the active current adjustment amounts of the phases, where the active currents of the phases are active currents of the power grid side at the phases, respectively, including: calculating a first average active current according to the active currents of the phases; and according to the first average active current and the active current of each phase, adopting a preset active current loop control algorithm to respectively calculate the active current adjustment quantity of each phase.

Optionally, the determining module 1003 is specifically configured to determine, for each phase, a reactive current of each phase at the grid side, and determine, according to the reactive current of each phase, a reactive current adjustment amount of each phase, where the determining includes: and according to the reactive current of each phase and a preset reference reactive current value, adopting a preset reactive current loop control algorithm to respectively calculate reactive current adjustment quantity of each phase.

Optionally, the calculating module 1002 is specifically configured to calculate, according to the active currents of the phases, the active current adjustment amounts of the phases, where the active currents of the phases are active currents of the load side at the phases, respectively, including: calculating a second average active current according to the active currents of the phases; and obtaining the active current adjustment quantity of each phase according to the difference value of the active current of each phase and the second average active current.

Optionally, the determining module 1003 is specifically configured to determine, for each phase, a reactive current of each phase at the load side, and determine, according to the reactive current of each phase, a reactive current adjustment amount of each phase, respectively, including: and determining the reactive current of each phase as the reactive current adjustment quantity of each phase.

Optionally, an obtaining module 1001 is specifically configured to detect a current of three phases and a voltage of three phases corresponding to a preset ac bus; and respectively determining the active current of each phase and the reactive current of each phase according to the current of the three phases and the voltage of the three phases.

Optionally, an acquiring module 1001 is specifically configured to acquire power and power factor information of each three-phase conversion device; and determining the active current of each phase and the reactive current of each phase according to the power of each three-phase conversion device, the power factor information of each three-phase conversion device and the voltage of a preset alternating current power supply.

The above modules may be one or more integrated circuits configured to implement the above methods, for example: one or more application specific integrated circuits (Application Specific Integrated Circuit, abbreviated as ASIC), or one or more microprocessors (digital singnal processor, abbreviated as DSP), or one or more field programmable gate arrays (Field Programmable Gate Array, abbreviated as FPGA), or the like. For another example, when a module above is implemented in the form of a processing element scheduler code, the processing element may be a general-purpose processor, such as a central processing unit (Central Processing Unit, CPU) or other processor that may invoke the program code. For another example, the modules may be integrated together and implemented in the form of a system-on-a-chip (SOC).

Fig. 11 is a schematic diagram of a control device according to an embodiment of the present application, where the control device may be a device with a computing function.

The control device includes: a processor 1101, a storage medium 1102, and a bus 1103. The processor 1101 and the storage medium 1102 are connected by a bus 1103.

The storage medium 1102 is used to store a program, and the processor 1101 calls the program stored in the storage medium 1102 to execute the above-described method embodiment. The specific implementation manner and the technical effect are similar, and are not repeated here.

Optionally, the present invention also provides a program product, such as a computer readable storage medium, comprising a program for performing the above-described method embodiments when being executed by a processor.

In the several embodiments provided by the present invention, it should be understood that the disclosed apparatus and method may be implemented in other manners. For example, the apparatus embodiments described above are merely illustrative, e.g., the division of the units is merely a logical function division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another system, or some features may be omitted or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, which may be in electrical, mechanical or other form.

The units described as separate units may or may not be physically separate, and units shown as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in the embodiments of the present invention may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit. The integrated units may be implemented in hardware or in hardware plus software functional units.

The integrated units implemented in the form of software functional units described above may be stored in a computer readable storage medium. The software functional unit is stored in a storage medium, and includes several instructions for causing a control device (which may be a personal computer, a server, or a network device, etc.) or a processor (english: processor) to perform part of the steps of the methods according to the embodiments of the invention. And the aforementioned storage medium includes: u disk, mobile hard disk, read-Only Memory (ROM), random access Memory (Random Access Memory, RAM), magnetic disk or optical disk, etc.

The foregoing is merely a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think about changes or substitutions within the technical scope of the present application, and the changes or substitutions are covered by the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A load adjustment method, comprising:

according to the current adjustment quantity of each phase, respectively determining a target current adjustment quantity of each three-phase conversion device in the phases of at least one three-phase conversion device to be scheduled; the three-phase conversion equipment is independently operated composite charging equipment;

sending the target current adjustment quantity of each phase to each three-phase conversion device, so that each three-phase conversion device respectively adjusts the load of each phase on the preset alternating current bus according to the target current adjustment quantity of each phase;

the power current includes: and calculating the current adjustment quantity of each phase according to the power current of each phase, wherein the current adjustment quantity comprises the following steps:

2. The load adjustment method according to claim 1, wherein if the number of the three-phase transformation devices is at least one, the determining, according to the active current adjustment amounts of the respective phases, the target active current adjustment amounts of each of the at least one three-phase transformation devices to be scheduled in the respective phases includes:

3. The load adjusting method according to claim 1, wherein if the number of the three-phase transforming devices is at least one, the determining the target reactive current adjustment amount of each three-phase transforming device in each phase according to the reactive current adjustment amount of each phase includes:

4. The load regulation method of claim 1, wherein the active currents of the phases are active currents of the power grid side at the phases; the step of calculating the active current adjustment quantity of each phase according to the active current of each phase comprises the following steps:

5. The load regulation method of claim 1, wherein the reactive current of each phase is a reactive current of each phase on the grid side; and respectively determining reactive current adjustment amounts of the phases according to the reactive currents of the phases, wherein the reactive current adjustment amounts comprise:

6. The load adjustment method according to claim 1, characterized in that the active current of each phase is the active current of each phase on the load side; the step of calculating the active current adjustment quantity of each phase according to the active current of each phase comprises the following steps:

7. The load regulation method of claim 1, wherein the reactive current of each phase is a reactive current of each phase at a load side; and respectively determining reactive current adjustment amounts of the phases according to the reactive currents of the phases, wherein the reactive current adjustment amounts comprise:

8. The load adjustment method according to claim 1, wherein the obtaining the power current of each of the three phases corresponding to the preset ac bus includes:

9. The load adjustment method according to claim 1, wherein the obtaining the power current of each of the three phases corresponding to the preset ac bus includes:

10. A load regulation system, comprising: the device comprises a transformer, at least one three-phase conversion device, a control device and a load; the three-phase conversion equipment is independently operated composite charging equipment;

the transformer is used for being electrically connected with a preset alternating current bus, the at least one three-phase conversion device is used for being electrically connected with the preset alternating current bus, the load is used for being electrically connected with the preset alternating current bus, the control device is in communication connection with a control unit of each three-phase conversion device, the control device is electrically connected with an outgoing line of the transformer, the control device is further electrically connected with an incoming line of the load, and the control device is used for executing the load adjusting method according to any one of claims 1-9.