WO2021077753A1

WO2021077753A1 - Comprehensive control method and system that ensure voltage safety in power recovery stage of multiple feed-in dc system

Info

Publication number: WO2021077753A1
Application number: PCT/CN2020/094106
Authority: WO
Inventors: 王洪涛; 杨善栋; 刘玉田; 杨冬; 马欢; 赵康
Original assignee: 国网山东省电力公司电力科学研究院; 山东大学; 国家电网有限公司
Priority date: 2019-10-22
Filing date: 2020-06-03
Publication date: 2021-04-29
Also published as: KR20210105882A; KR102551927B1; CN111064179B; CN111064179A

Abstract

Disclosed are a comprehensive control method and system that ensure voltage safety in a power recovery stage of a multiple feed-in DC system, the method comprising: linearizing a power flow equation of an AC-DC system to obtain a sensitivity matrix of a node voltage with respect to DC transmission active power and reactive power emitted by a reactive compensation device. A DC power recovery optimization model is created with the node voltage deviation within a safe range as a constraint, and the model is solved to obtain an optimal power recovery amount at every time step for each DC system with voltage safety as a precondition; a reactive compensation device increase optimization model is created with a goal of minimal node voltage deviation, and the model is solved to obtain an optimal increase amount for each reactive compensation device after the DC power recovery is completed at every time step, so that the node voltage deviation caused by the DC power recovery is minimized. The present invention may provide online guidance for power recovery control of a multiple feed-in DC system, so as to fully ensure the voltage safety and recovery efficiency of the recovery process.

Description

Comprehensive control method and system for ensuring voltage safety during power recovery stage of multi-feed DC system

Technical field

The invention relates to the technical field of DC system power recovery, and in particular to a comprehensive control method and system for ensuring voltage safety in a multi-feed DC system power recovery stage.

Background technique

The statements in this section merely provide background information related to the present invention, and do not necessarily constitute prior art.

Due to the dense DC drop points in the multi-feed DC system, the electrical coupling is enhanced, and its operating mechanism is more complicated. At present, domestic and foreign power grids have little experience in the recovery operation of multi-infeed DC systems after a blackout. Generally, the AC system is restored first, and the DC system is restored last. However, the DC system has the advantages of large transmission capacity and fast power adjustment. If the recovery capacity of the DC system can be fully utilized in the system recovery process, the recovery speed of the system will be greatly accelerated. Therefore, the rapid and safe recovery plan for the multi-feed DC system Research has important practical significance.

Participation in the recovery of the DC system needs to meet certain safety constraints. At present, the safety control research on the start-up phase of the DC system has been relatively complete, which can solve the safety of the start-up of the DC system. However, the safety control scheme for the power recovery stage after the start of the DC system is relatively lacking. The DC system consumes a large amount of reactive power during normal operation. As the active power delivered by the DC system increases, the reactive power consumed by the DC system increases proportionally. Therefore, in the power recovery stage of multi-infeed DC, the problem of AC voltage drop caused by insufficient reactive power of the system is very significant. Therefore, it is necessary to pay attention to the voltage safety of the power recovery process of the multi-infeed DC system, and provide a comprehensive recovery control scheme to ensure the voltage safety.

Summary of the invention

In order to solve the problem of AC voltage drop caused by the power recovery of the multi-infeed DC system, the present invention proposes a comprehensive control method and system for ensuring voltage safety during the power recovery stage of the multi-infeed DC system, which can ensure the power recovery stage of the multi-infeed DC system. Voltage safety and improve recovery efficiency.

In some embodiments, the following technical solutions are adopted:

The comprehensive control method for ensuring voltage safety during the power recovery phase of the multi-infeed DC system includes:

According to the initial state of each time step, establish the power flow equation of the AC/DC system;

Obtain the sensitivity matrix of the node voltage with respect to the active power delivered by the DC system, and the sensitivity matrix of the node voltage with respect to the reactive power emitted by the reactive power compensation device;

According to the sensitivity matrix of the node voltage with respect to the DC transmission active power, an optimization model for the DC active power recovery is established with the deviation of all node voltages in the safe range as the constraint, and the model is solved to obtain the DC system's performance at each time step under the premise of voltage safety. The optimal recovery amount of active power;

According to the sensitivity matrix of the node voltage with respect to the reactive power emitted by the reactive power compensation device, an optimization model for the increased investment of the reactive power compensation device with the goal of the minimum square sum of the node voltage deviation is established, and the model is solved to obtain the completion of the DC power recovery at each time step After the optimal increase of the reactive power compensation device, the node voltage deviation caused by the DC power recovery is minimized.

In other embodiments, the following technical solutions are adopted:

A comprehensive control system that guarantees voltage safety during the power recovery phase of the multi-infeed DC system, including:

A device used to establish the power flow equation of the AC/DC system according to the initial state of each time step;

A device for obtaining the sensitivity matrix of the node voltage with respect to the active power delivered by the DC system, and a device for the sensitivity matrix of the node voltage with respect to the reactive power emitted by the reactive power compensation device;

A device used to establish a DC active power recovery optimization model with all node voltage deviations within a safe range based on the sensitivity matrix of the node voltage with respect to the DC transmission active power; used to solve the model to obtain the voltage safety premise at each time step The device for the optimal recovery amount of active power of each DC system below;

A device used to establish a reactive power compensation device increase investment optimization model aiming at the minimum square sum of the node voltage deviation according to the sensitivity matrix of the reactive power emitted by the reactive power compensation device according to the node voltage; After the completion of the one-time DC power recovery, the optimal increase of each reactive power compensation device is a device that minimizes the node voltage deviation caused by the DC power recovery.

In other embodiments, the following technical solutions are adopted:

A terminal device, which includes a processor and a computer-readable storage medium, the processor is used to implement each instruction; the computer-readable storage medium is used to store a plurality of instructions, the instructions are suitable for being loaded by the processor and executing the above-mentioned multi-feed A comprehensive control method to ensure voltage safety during the power recovery phase of the DC system.

In other embodiments, the following technical solutions are adopted:

A computer-readable storage medium stores a plurality of instructions, and the instructions are suitable for being loaded by a processor of a terminal device and executing the above-mentioned comprehensive control method for ensuring voltage safety during the power recovery phase of a multi-feed DC system.

Compared with the prior art, the beneficial effects of the present invention are:

The method of the present invention can solve the problem of AC voltage drop caused by the power recovery of the DC system; in each time step of the recovery, the method optimizes the recovery amount of the active power of the DC system, and improves the recovery efficiency under the premise of ensuring the safety of the system voltage , And then optimize the increased investment of the reactive power compensation device to minimize the voltage deviation of each node caused by the recovery of DC power, and to keep the system voltage constant.

Description of the drawings

Fig. 1 is a flow chart of a comprehensive control method for ensuring voltage safety during the power recovery phase of a multi-feed DC system in the first embodiment of the present invention;

Figure 2 is an iterative flow chart of the method in the first embodiment of the present invention;

Figure 3 is a structural diagram of the power system in the first embodiment of the present invention;

Fig. 4 is a curve of node voltage change in the DC power recovery phase using the integrated control method of the present invention;

Fig. 5 is a curve of node voltage change in the DC power recovery stage without the integrated control method of the present invention.

Detailed ways

It should be pointed out that the following detailed descriptions are all illustrative and are intended to provide further explanations for the application. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present application belongs.

It should be noted that the terms used here are only for describing specific embodiments, and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should also be understood that when the terms "comprising" and/or "including" are used in this specification, they indicate There are features, steps, operations, devices, components, and/or combinations thereof.

Example one

The reactive power level of the system during the power recovery process of the multi-infeed DC system is the main factor that affects the node voltage. Therefore, the variables that determine the node voltage are: the reactive power absorbed by the DC inverter and the reactive power generated by the reactive compensation device. The reactive power absorbed by the DC system is directly related to the active power recovered by the DC system. Therefore, reasonable regulation of the power recovery of each DC system at each time step can ensure the safety of the node voltage and improve the recovery speed; DC power recovery at each time step After completion, a certain voltage deviation will inevitably be caused, and the voltage deviation caused by the recovery of the DC power can be minimized through a reasonable increase in the reactive power compensation equipment in the system, and the voltage can be kept constant. In addition, the multi-infeed DC system has mutual influences between the DC systems. How to accurately account for the interaction between the DC systems is of great significance to reliably guarantee the voltage safety of the multi-infeed DC system power recovery process.

In one or more embodiments, a comprehensive control method for ensuring voltage safety during the power recovery phase of a multi-feed DC system is disclosed. As shown in Figures 1 and 2, the method is carried out in multiple time steps. The steps include the following steps:

(1) According to the initial state of each time step, establish the power flow equation of the AC and DC system;

(2) Obtain the sensitivity matrix of the node voltage with respect to the active power delivered by the DC system, and the sensitivity matrix of the node voltage with respect to the reactive power emitted by the reactive power compensation device;

(3) According to the sensitivity matrix of the node voltage with respect to the DC transmission active power, establish a DC active power recovery optimization model with all node voltage deviations in the safe range as the constraint, and solve the model to obtain the various values at each time step under the premise of voltage safety. The optimal recovery amount of active power of the DC system;

(4) According to the sensitivity matrix of the reactive power emitted by the reactive power compensation device based on the node voltage, an optimization model for the increased investment of the reactive power compensation device with the goal of the minimum square sum of the node voltage deviation is established, and the model is solved to obtain the DC at each time step. After the power recovery is completed, the optimal increase of the reactive power compensation devices minimizes the node voltage deviation caused by the DC power recovery.

Among them, in step (1), the power flow equation of the AC and DC system is composed of the power flow equation of the AC system and the operation equation of the DC system. The form of the power flow equation of the AC system is:

P _G,i -P _L,i -P _a,i =0

Q _G,i -Q _L,i -Q _a,i =0

Among them, P _G,i and Q _G,i are the active power and reactive power sent by the AC generator set to node i; P _L,i and Q _L,i are the active power and reactive power consumed by the load of node i; P _a,i and Q _a,i are the active power and reactive power injected into the AC node i, and the calculation form is:

Among them, U _i and U _j are the voltages of nodes i and j, and G _ij , δ _ij and B _ij are the conductance, power angle difference, and susceptance between nodes i and j, respectively.

The operating equation form of the DC system is as follows:

According to the control equations of the DC system under different control modes, the operating equations of the DC system under certain control parameters can be obtained.

P _d,i =f(U _i ,δ _i )

Among them, P _d,i is the active power injected by the DC system fed into node i, and Q _d,i is the reactive power injected by the DC system fed into node i;

Is the power factor angle of the DC system inverter fed into node i; δ _i is the power angle of node i.

The operating equation of the DC system quantitatively expresses the relationship between the active power and reactive power of the DC output and the voltage amplitude and phase angle of the commutation bus.

Using the power balance equation at the converter bus, the power flow equation of the AC and DC system can be obtained. The form of the power flow equation of the AC/DC system is as follows:

P _G,i +P _d,i -P _L,i -P _a,i =0

Q _G,i +Q _d,i -Q _L,i -Q _a,i = 0

In step (2), the sensitivity matrix of the node voltage to the active power of DC transmission and the sensitivity matrix of the node voltage to the reactive power emitted by the reactive power compensation device are obtained through the power flow equation of the AC and DC system.

In order to calculate the sensitivity matrix of the node voltage with respect to the active power of the DC transmission, the reactive power absorbed by the DC system needs to be represented by the active power transmitted by the DC system according to the power factor of the DC inverter, and then substituted into the node voltage. In the power sensitivity matrix, sort the available node voltage sensitivity matrix to the DC transmission active power.

The reactive power emitted by the reactive power compensation device is the reactive power injected by the node, and the sensitivity matrix of the node voltage to the reactive power injected into the node is the sensitivity matrix of the node voltage to the reactive power emitted by the reactive power compensation device.

First, use the AC/DC power flow equation to obtain the partial derivative of the voltage amplitude and phase angle of each node to obtain the power flow Jacobian matrix of the AC/DC system. The form is as follows:

In the formula, J _Pδ , J _PU , J _Qδ and J _QU are the corresponding block matrices of the Jacobian matrix respectively. Only consider the relationship between reactive power and voltage amplitude, so that the AC/DC system power flow Jacobian matrix is transformed into a dimensionality reduction matrix:

ΔQ=J _QU ΔU;

Reverse the above formula to get the sensitivity equation of node voltage to reactive power:

among them,

Is the sensitivity matrix of node voltage to reactive power. Through the sensitivity matrix of node voltage to reactive power, the sensitivity equation of node voltage to DC transmission active power can be obtained as:

Where

Is the power factor angle of the DC system inverter fed into node i;

Is the sensitivity matrix of the node voltage to the DC transmission active power; ΔP _d is the recovery amount of the DC power.

Through the sensitivity matrix of node voltage to reactive power, the sensitivity equation of node voltage to reactive power emitted by reactive power compensation device can be obtained as:

In the formula, ΔQ _c is the increased reactive power of the reactive power compensation device.

In step (3), the establishment process of the DC transmission active power recovery optimization model constrained by the node voltage deviation within the safe range is as follows:

The decision variable is ΔP _d,i , that is, the amount of active power recovery of each DC system at each time step.

The optimization goal is to maximize the amount of DC power recovery per time step:

The equation constraint is the sensitivity equation of the node voltage to the active power of DC transmission:

The inequality constraints are the DC power upper limit constraint and the node voltage safety range constraint:

P _d,i +ΔP _d,i ≤P _dmax,i

U _i +ΔU _i >0.9U _N

In the formula, P _dmax,i is the upper limit of DC transmission power; U _N,i is the rated voltage of node i, and 0.9U _N,i is the safe lower limit of node voltage.

Furthermore, the DC transmission active power recovery optimization model constrained by the node voltage deviation within the safe range can be solved by the linear programming function of CPLEX, and the maximum value of each DC system at each time step is obtained on the premise that the node voltage is within the safe range. Excellent recovery power. The calculation results are sent to the controllers of each DC system for DC active power recovery control.

In step (4), the establishment process of the optimization model of the increased investment of the reactive power compensation device with the goal of the minimum square sum of the node voltage deviation value is as follows:

The decision variable is ΔQ _C,i , that is, the increased investment of each node reactive power compensation device after the completion of the DC power recovery at each time step.

The optimization goal is to minimize the sum of squared deviations of the node voltage:

The equation constraint is the sensitivity equation of the node voltage to the reactive power emitted by the reactive power compensation device:

The inequality constraint is the upper limit constraint on the capacity of the reactive power compensation device: Q _C,i +ΔQ _C,i ≤Q _Cmax,i .

In the formula, Q _Cmax,i is the upper limit of the capacity of the reactive power compensation device.

Further, the optimization model of the increased investment of the reactive power compensation device with the goal of the minimum square sum of the node voltage deviation value can be solved by the linear programming function of CPLEX, and the maximum value of the reactive power compensation device after the completion of the DC power recovery at each time step is obtained. Optimal increase in investment volume minimizes the node voltage deviation caused by DC power recovery. The calculation result is sent to the reactive power compensation equipment controller of each substation for reactive power compensation control.

In this embodiment, the 4-DC fed 39-node system shown in FIG. 3 is taken as an example to further illustrate the specific implementation process of the present invention.

The formation method of the power system in this embodiment is to improve on the IEEE-39 node standard power system, and modify the generator sets at

nodes

35, 36, 37, and 38 to feed-in DC systems; the dotted line in Figure 3 indicates that it has not been restored It is assumed that the initial power of each DC system in the power recovery phase is 10% of the rated power, and the recovery starts at t=0, and the time step length is 5min. The specific implementation process of this example includes:

(1) Obtain the initial power grid information at each time step, including node voltage, load power, generator power, DC control parameters, DC transmission power and reactive power compensation device input to form the AC and DC system power flow equation.

(2) Obtain the partial derivative of the power flow equation of the AC and DC system to obtain the power flow Jacobian matrix, extract the block matrix reflecting the influence of the node voltage on the reactive power, and perform the inverse operation to obtain the sensitivity matrix of the node voltage with respect to the reactive power, and further obtain the node voltage The sensitivity matrix of the active power of DC transmission and the sensitivity matrix of the node voltage of the reactive power emitted by the reactive power compensation device.

(3) Use the sensitivity matrix of the node voltage with respect to the active power of the DC transmission to establish a DC power recovery optimization model, and use CPLEX to solve the model to obtain the optimal power recovery amount of each DC system under the premise of voltage safety, and send it to each DC The converter station controller executes power recovery control according to the optimized results.

(4) Use the sensitivity matrix of the node voltage with respect to the active power emitted by the reactive power compensation device to establish an optimization model for the increased investment of the reactive power compensation device, and use CPLEX to solve the model to obtain the reactive power compensation that minimizes the voltage deviation caused by the DC power recovery The optimal increase investment plan of the device is issued to the reactive power compensation controller of each substation to execute the reactive power compensation control according to the optimized result.

If all 4 DC system powers are not restored, then enter the next time step of optimal control; if all 4 DC powers are restored, the multi-feed DC system power recovery phase ends.

The node 16 is set as the central node of the system in the embodiment, and after each operation, the voltage of the node 16 is calculated by the power flow calculation software to reflect the overall voltage level of the system. FIG. 4 records the voltage change of the node 16 in the power recovery process of the multi-feed DC system using the integrated control method of the present invention. As shown in Figure 4, the node voltage drop caused by the DC power recovery at each time step is within a safe range. After the reactive power compensation control, the node voltage returns to a level close to the rated voltage. The entire multi-feed DC system power recovery process Voltage safety is guaranteed, and the total time for DC power recovery is 20 minutes. Fig. 5 records the voltage change of the node 16 in the power recovery process of the multi-feed DC system without the integrated control method of the present invention. Each DC system recovers 10% of the power at each time step, and the reactive power compensation control is not performed in time.

Figure 5 shows that because the comprehensive control method to ensure voltage safety is not adopted, as the power of the multi-infeed DC system is restored, the system voltage level is severely reduced, which seriously threatens the safety of the system; in addition, the total time for DC power restoration is 40 Minutes, which is greater than the total time required for DC power recovery using the integrated control method of the present invention. This reflects that the present invention has important guiding significance for improving the safety and efficiency of the recovery of the multi-infeed DC system.

Example two

In one or more embodiments, a comprehensive control system for ensuring voltage safety during the power recovery phase of a multi-feed DC system is disclosed, including:

In other embodiments, a terminal device is disclosed, which includes a processor and a computer-readable storage medium, where the processor is used to implement instructions; the computer-readable storage medium is used to store multiple instructions, and the instructions are suitable for The processor loads and executes the integrated control method for ensuring voltage safety during the power recovery phase of the multi-feed DC system described in the first embodiment.

In other embodiments, a computer-readable storage medium is disclosed, in which a plurality of instructions are stored, and the instructions are suitable for being loaded by a processor of a terminal device and executing the multi-feed DC system described in the first embodiment. A comprehensive control method to ensure voltage safety during the power recovery phase.

Although the specific embodiments of the present invention are described above in conjunction with the accompanying drawings, they do not limit the scope of protection of the present invention. Those skilled in the art should understand that on the basis of the technical solutions of the present invention, those skilled in the art do not need to make creative efforts. Various modifications or variations that can be made are still within the protection scope of the present invention.

Claims

The comprehensive control method for ensuring voltage safety during the power recovery phase of the multi-infeed DC system is characterized in that it includes:

According to the initial state of each time step, establish the power flow equation of the AC/DC system;

Obtain the sensitivity matrix of the node voltage with respect to the active power delivered by the DC system, and the sensitivity matrix of the node voltage with respect to the reactive power emitted by the reactive power compensation device;

According to the sensitivity matrix of the node voltage with respect to the DC transmission active power, an optimization model for the DC active power recovery is established with the deviation of all node voltages in the safe range as the constraint, and the model is solved to obtain the DC system's performance at each time step under the premise of voltage safety. The optimal recovery amount of active power;

According to the sensitivity matrix of the node voltage with respect to the reactive power emitted by the reactive power compensation device, an optimization model for the increased investment of the reactive power compensation device with the goal of the minimum square sum of the node voltage deviation is established, and the model is solved to obtain the completion of the DC power recovery at each time step After the optimal increase of the reactive power compensation device, the node voltage deviation caused by the DC power recovery is minimized.
The comprehensive control method for ensuring voltage safety during the power recovery phase of the multi-infeed DC system according to claim 1, wherein the process of establishing the power flow equation of the AC and DC system is specifically:

According to the relationship between the active power and reactive power sent by the AC generator set to node i, the active power and reactive power consumed by the load of node i, and the active power and reactive power injected into the AC node i, establish the AC system flow equation;

According to the relationship between the active power and reactive power of the DC output and the voltage amplitude and phase angle of the commutation bus, the operating equation of the DC system is established;

At the converter bus, the power balance equation is established according to the power flow equation of the AC system and the operating equation of the DC system, and the power flow equation of the AC and DC system is obtained.
The comprehensive control method for ensuring voltage safety during the power recovery phase of the multi-infeed DC system according to claim 1, wherein the obtaining a sensitivity matrix of the node voltage with respect to the active power delivered by the DC system is specifically:

Use the AC/DC power flow equation to obtain the partial derivative of the voltage amplitude and phase angle of each node to obtain the power flow Jacobian matrix of the AC/DC system; extract the block matrix reflecting the influence of the node voltage amplitude on the reactive power injected into the node from the Jacobian matrix Inverse operation obtains the sensitivity matrix of node voltage with respect to node injection reactive power;

According to the power factor of the DC inverter, the reactive power absorbed by the DC system is represented by the active power delivered by the DC system, and then substituted into the sensitivity matrix of the node voltage with respect to the reactive power injected by the node to obtain the node voltage with respect to the active power delivered by the DC system Power sensitivity matrix.
The comprehensive control method for ensuring voltage safety during the power recovery phase of the multi-infeed DC system according to claim 1, wherein obtaining the sensitivity matrix of the node voltage with respect to the reactive power emitted by the reactive power compensation device is specifically:

Use the AC/DC power flow equation to obtain the partial derivative of the voltage amplitude and phase angle of each node to obtain the power flow Jacobian matrix of the AC/DC system; extract the block matrix reflecting the influence of the node voltage amplitude on the reactive power injected into the node from the Jacobian matrix The inversion operation obtains the sensitivity matrix of the node voltage with respect to the reactive power injected into the node, that is, the sensitivity matrix of the node voltage with respect to the reactive power emitted by the reactive power compensation device.
The comprehensive control method for ensuring voltage safety during the power recovery phase of the multi-infeed DC system according to claim 1, characterized in that an optimization model for DC active power recovery is established with the voltage deviations of all nodes within a safe range as a constraint, specifically for:

Take the power recovery amount of each time step of each DC system as the decision variable; take the maximum DC active power recovery amount of each time step as the optimization goal; take the sensitivity equation of the node voltage with respect to the DC transmission active power as the equation constraint; take each node The constraint that the voltage deviation is within the safe range and the upper limit constraint of the DC system power recovery are used as inequality constraints, and the DC active power recovery optimization model is established.
The integrated control method for ensuring voltage safety during the power recovery phase of the multi-infeed DC system as claimed in claim 1, characterized in that an optimization model for the increased investment of the reactive power compensation device with the goal of the minimum square sum of the node voltage deviations is established ,Specifically:

Regarding the increased investment of the reactive power compensation device after the completion of the DC power recovery at each time step as the decision variable; taking the minimum square sum of the node voltage deviation caused by the DC power recovery as the optimization objective; taking the node voltage to generate reactive power with respect to the reactive power compensation device The power sensitivity equation is an equation constraint; the upper limit of the reactive power emitted by the reactive power compensation device is an inequality constraint, and an optimization model for the increased investment of the reactive power compensation device is established.
The comprehensive control method for ensuring voltage safety during the power recovery phase of the multi-infeed DC system according to claim 1, wherein the active power recovery optimization model and the reactive power compensation device increase investment optimization model are solved by CPLEX The linear programming function is used to solve the problem.
The integrated control system for ensuring voltage safety during the power recovery phase of the multi-infeed DC system is characterized in that it includes:

A device used to establish the power flow equation of the AC/DC system according to the initial state of each time step;

A device for obtaining the sensitivity matrix of the node voltage with respect to the active power delivered by the DC system, and a device for the sensitivity matrix of the node voltage with respect to the reactive power emitted by the reactive power compensation device;

A device used to establish a DC active power recovery optimization model with all node voltage deviations within a safe range based on the sensitivity matrix of the node voltage with respect to the DC transmission active power; used to solve the model to obtain the voltage safety premise at each time step The device for the optimal recovery amount of active power of each DC system below;

A device used to establish a reactive power compensation device increase investment optimization model aiming at the minimum square sum of the node voltage deviation according to the sensitivity matrix of the reactive power emitted by the reactive power compensation device according to the node voltage; The optimal increase in the investment of each reactive power compensation device after the completion of the one-time DC power recovery is a device that minimizes the node voltage deviation caused by the DC power recovery.
A terminal device comprising a processor and a computer-readable storage medium, the processor is used to implement each instruction; the computer-readable storage medium is used to store a plurality of instructions, characterized in that the instructions are suitable for being loaded and executed by the processor The comprehensive control method for ensuring voltage safety during the power recovery phase of the multi-feed DC system according to any one of claims 1-7.
A computer-readable storage medium, wherein a plurality of instructions are stored, wherein the instructions are adapted to be loaded by a processor of a terminal device and execute the multi-infeed DC system power according to any one of claims 1-7 A comprehensive control method to ensure voltage safety during the recovery phase.