KR20210105882A - Comprehensive control method and system that guarantees voltage stability in the power recovery stage of multi-phase DC system - Google Patents

Abstract

The present invention discloses a comprehensive control method and system that guarantees voltage stability in the multi-infeed DC system power recovery step. and obtaining a sensitivity matrix of the node voltage to the reactive power sent by the compensator. Build an optimization model of DC power recovery that is constrained within a safe range based on the amount of node deviation to obtain an answer, and on the premise of voltage safety, obtain the optimal recovery amount of power for each DC system for each time step; By building an optimization model of the amount of expansion of the reactive power compensator that aims to minimize the amount of node voltage deviation, the answer is obtained, Ensure that the node voltage deviation is minimized. According to the present invention, the voltage stability and recovery efficiency of the recovery process can be sufficiently ensured by instructing the multi-phase DC system power recovery control on-line.

Description

Comprehensive control method and system that guarantees voltage stability in the power recovery stage of multi-phase DC system

The present invention relates to the field of DC system power recovery technology, and more particularly, to a comprehensive control method and system for ensuring voltage stability in a multi-infeed DC system power recovery step.

The statements in this section have provided only background information related to the present invention and do not necessarily constitute prior art.

In the multi-phase direct current system, the drop point is concentrated, the electrical coupling is strengthened, and the operation mechanism is more complicated. Currently, domestic and foreign power grids have very little experience in recovering operation after a large-scale power outage of multiple DC systems, so usually, the AC system is restored first and the DC system is restored last. However, the DC system has the advantage of large transport capacity and fast power control, and if the recovery capacity of the DC system is sufficiently used during the system recovery process, the recovery speed of the system can be greatly accelerated. The research on this is very important and has practical significance.

For a DC system to participate in recovery, certain safety constraints must be satisfied. Currently, research on safety control in the operation stage of the DC system is relatively complete, and it is possible to realize the safety of the operation of the DC system. However, the safety control plan for the power recovery stage after the DC system is operated is relatively insufficient. The DC system must consume a large amount of reactive power when operating normally. As the effective power transported by the DC system increases, the reactive power consumed by the DC system increases proportionally. Therefore, in the power recovery step of the multiphase DC, the problem that the AC voltage is lowered due to insufficient system reactive power is very clear. Therefore, it is necessary to pay attention to the voltage safety of the multi-phase DC system power recovery process and to present a comprehensive recovery control plan that guarantees the voltage stability.

In order to solve the problem that the AC voltage is lowered due to multi-infeed DC system power recovery, the present invention can ensure voltage stability and improve recovery efficiency in the multi-infeed DC system power recovery step in the multi-phase DC system power recovery step. It provides a comprehensive control method and system that guarantees voltage stability.

In some implementations, using the following technical measures,

establishing a power flow equation of the AC-DC system based on the initial state for each time step;

obtaining a sensitivity matrix of the node voltage with respect to the effective power transmitted by the DC system and a sensitivity matrix of the node voltage with respect to the reactive power transmitted by the reactive compensation device;

According to the sensitivity matrix of the node voltage for the effective power transported by DC, an optimization model for the recovery of DC active power that is constrained within a safe range by the amount of voltage deviation of all nodes is established, and the model is obtained and voltage safety is premised for each time step. to obtain an optimal recovery amount of effective power for each DC system;

Based on the sensitivity matrix of the node voltage to the reactive power sent by the reactive power compensation device, an optimization model of the amount of expansion of the reactive power device aiming at the square and minimization of the deviation of the node voltage is constructed, and the model is obtained by time step Voltage in the multi-phase DC system power recovery step, comprising: obtaining an optimal expansion amount for each ineffective compensation device after DC power recovery is completed, so that the node voltage deviation caused by DC power recovery is reduced to a minimum It provides a comprehensive control method that guarantees stability.

In some other embodiments, using the technical solution below,

A device used to build the power flow equation of a AC-DC system based on the initial state per time step;

a device used to obtain a sensitivity matrix of node voltages with respect to the effective power transmitted by the DC system, and a device used for obtaining a sensitivity matrix of node voltages with respect to the reactive power transmitted by the reactive compensator;

a device used to construct an optimization model of DC effective power recovery that is constrained within a safe range by the amount of deviation of all node voltages according to the sensitivity matrix of the node voltage with respect to the effective power transported by DC; A device used to obtain an optimal recovery amount of effective power for each DC system on the premise of voltage safety for each time step by obtaining a corresponding model;

A device used to construct an optimization model of the expansion amount of the reactive power device that aims to square and minimize the amount of deviation of the node voltage based on the sensitivity matrix of the node voltage to the reactive power sent by the reactive power compensation device; A device used to obtain an optimal expansion amount for each invalid compensation device after DC power recovery for each time step is completed by obtaining a model, and to minimize the node voltage deviation caused by DC power recovery; characterized by comprising: to provide a comprehensive control system that guarantees voltage stability in the multi-phase DC system power recovery stage.

In some other implementations, using the following technical solution,

a processor and a computer readable storage medium, wherein the processor is used to implement each instruction; A computer-readable storage medium is used to store a plurality of instructions, and the instructions are loaded by the processor to provide a terminal device suitable for executing a comprehensive control method for ensuring voltage stability in the multi-phase DC system power recovery step. .

In some other implementations, using the following technical solution,

A plurality of commands are stored therein, and the commands are loaded by the processor of the terminal device to provide a computer-readable storage medium suitable for executing a comprehensive control method for ensuring voltage stability in the multi-phase DC system power recovery step.

Compared to the prior art, the present invention achieves the following effects.

The method of the present invention can solve the problem that the AC voltage is lowered by restoring the DC system power; Within each time step of recovery, the method optimizes the recovery amount of the DC system effective power to improve the recovery efficiency under the premise of ensuring system voltage stability, and then optimizes the expansion amount of the reactive compensation device to restore DC power. The system voltage is maintained constant by minimizing the amount of voltage deviation for each node.

1 is a flowchart of a comprehensive control method for ensuring voltage stability in a multi-infeed DC system power recovery step in Embodiment 1 of the present invention;
2 is an iterative flow diagram of the method in Example 1 of the present invention;
3 is a block diagram of a power system in Embodiment 1 of the present invention;
4 is a node voltage change curve in the DC power recovery step of the comprehensive control method according to the present invention;
5 is a node voltage change curve in the DC power recovery step of the comprehensive control method according to the present invention.

It is indicated that the following detailed description is all exemplary, and the purpose is to further describe the present application. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

Above all, the terminology used herein is only for the purpose of describing specific embodiments, and is not intended to limit the exemplary embodiments according to the present application. Unless the context clearly indicates otherwise, terms used herein are intended to include both the singular and the plural, and, in addition, when the terms “including” and/or “inclusive” are used in the specification, they are characterized; It is also to be understood that a step, operation, element, assembly, and/or combination thereof is specified to exist.

Example 1

In the multi-infeed DC system power recovery process, the reactive power level of the system is a major factor influencing the node voltage. Therefore, the variable determining the node voltage is the reactive power absorbed by the DC inverter and the reactive power sent by the reactive power compensator. However, since the reactive power absorbed by the DC system is directly related to the effective power recovered by the DC system, it is possible to ensure the voltage safety of the node and improve the recovery speed by rationally adjusting the power recovery amount for each DC system for each time step. there is; After the DC power recovery for each time step is completed, the voltage deviation inevitably occurs. By expanding the reactive power compensation facility in the system, the voltage deviation caused by the DC power recovery can be minimized and the voltage constant can be maintained. In addition, in a multi-phase DC system, there is a mutual influence between the DC systems, and how to accurately count the interaction between the DC systems has important significance in reliably guaranteeing the voltage stability in the power recovery process of the multi-phase DC system.

In one or more embodiments, a comprehensive control method for ensuring voltage stability in the multi-phase DC system power recovery step has been disclosed, and as shown in FIGS. 1 and 2, the method is divided into a plurality of time steps and implemented, According to the time staff,

(1) establishing a power flow equation of the AC-DC system based on the initial state for each time step;

(2) obtaining a sensitivity matrix of the node voltage with respect to the effective power transmitted by the DC system and a sensitivity matrix of the node voltage with respect to the reactive power transmitted by the reactive compensator;

(3) According to the sensitivity matrix of the node voltage with respect to the effective power transported by DC, an optimization model of DC effective power recovery that is constrained within a safe range by the amount of deviation of all node voltages is established, and the model is obtained to ensure voltage safety for each time step. obtaining an optimal recovery amount of effective power for each DC system on the premise of ;

(4) Based on the sensitivity matrix of the node voltage to the reactive power sent by the reactive power compensation device, an optimization model of the amount of expansion of the reactive power device aimed at the square and minimization of the deviation of the node voltage is constructed, and the model is obtained and obtaining an optimal expansion amount for each invalid compensation device after the DC power recovery for each time step is completed, so that the node voltage deviation caused by the DC power recovery is minimized.

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

이며,

is,

와

은 교류발전유닛이 노드

에게 발송하는 유효 파워와 무효 파워이며;

와

은 노드

의 부하 소모의 유효 파워와 무효 파워이며;

와

은 교류를 주입하는 노드

의 유효 파워와 무효 파워이고 그 계산 형식은,From here,

Wow

The AC power unit is a node

effective power and reactive power sent to;

Wow

silver node

The load consumption of is the active power and reactive power;

Wow

silver node injecting alternating current

is the active power and reactive power of , and its calculation form is,

이며,

is,

와

는 노드

,

의 전압이고

,

,

는 각각 노드

,

간의 전기 전도, 파워 앵글(power angle) 차, 서셉턴스(susceptance)이다.From here,

Wow

is the node

,

is the voltage of

,

,

is each node

,

electrical conduction between Power angle difference, susceptance.

The operating equation of the DC system is as follows.

Based on the control equation for each control method of the DC system, the DC system operation equation is obtained under the determined control parameters.

은 인피드(in feed) 노드

의 직류시스템이 주입한 유효 파워이고

은 인피드 노드

의 직류시스템이 주입한 무효 파워이며;

는 인피드 노드

의 직류시스템 인버터의 역률각(power factor angle)이며;

는 노드

의 파워 앵글(power angle)이다.From here,

is an in-feed node

of It is the effective power injected by the DC system.

is an infeed node

Reactive power injected by the DC system of

is the infeed node

is the power factor angle of the DC system inverter;

is the node

of is the power angle.

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

The rectification bus point can obtain the power flow equation of the bridge-DC system by operating the power balance equation. The form of the AC-DC system power flow equation is as follows.

In step (2), a sensitivity matrix of the node voltage with respect to the active power transmitted in DC and the sensitivity matrix of the node voltage with respect to the reactive power transmitted by the reactive compensator are obtained through the AC-DC system power flow equation.

To calculate the sensitivity matrix of the node voltage to the effective power transported by DC, the reactive power absorbed by the DC system is expressed as the effective power transported by the DC system based on the power coefficient of the DC inverter, and then the node injected By substituting and arranging the node voltage sensitivity matrix for reactive power, it is possible to obtain a node voltage sensitivity matrix for active power transported by direct current.

The reactive power sent by the reactive power compensator is the reactive power injected by the node. Therefore, the sensitivity matrix of the node voltage to the reactive power injected by the node is the node voltage to the reactive power sent by the reactive power compensator. It is a sensitivity matrix.

First, the one-way is obtained using the amplitude and phase angle of the cross-DC power flow equation for each node voltage to obtain the Jacobian matrix of the cross-DC system power flow, but the form is

이며,

is,

,

,

와

는 각각 야코비안 행렬의 상응되는 블록별 행렬이다. 무효 파워와 전압 진폭의 작용관계만 감안하여 교-직류시스템 전력 조류 야코비안 행렬을 차원축소(dimension reduction) 행렬인In the formula,

,

,

Wow

is the corresponding block-by-block matrix of each Jacobian matrix. Considering only the action relationship between reactive power and voltage amplitude, the cross-DC system power current Jacobian matrix is transformed into a dimension reduction matrix.

로 전환시키며;

converted to;

The equation to obtain the sensitivity of the node voltage to the reactive power by inverse of the above equation is

이며;

is;

는 무효 파워에 대한 노드 전압의 민감도 행렬이다. 무효 파워에 대한 노드 전압의 민감도 행렬을 통해 직류로 수송하는 유효 파워에 대한 노드 전압의 민감도을 얻을 수 있는 방정식은From here,

is the sensitivity matrix of the node voltage to reactive power. The equation to obtain the sensitivity of the node voltage to the active power transported in direct current through the sensitivity matrix of the node voltage to the reactive power is

이며;

is;

는 인피드 노드

의 직류시스템 인버터의 역률각이며;

는 직류로 수송하는 유효 파워에 대한 노드 전압의 민감도 행렬이며;

는 직류 파워의 회복량이다.In the formula,

is the infeed node

is the power factor angle of the DC system inverter;

is the sensitivity matrix of the node voltage to the effective power carrying in direct current;

is the amount of recovery of DC power.

The equation to obtain the sensitivity of the node voltage to the reactive power sent by the reactive power compensator through the sensitivity matrix of the node voltage to the reactive power is

이며,

is,

는 무효파워보상장치의 무효 파워 추가발송량이다.In the formula,

is the amount of additional reactive power sent by the reactive power compensation device.

In step (3), the DC active power constrained within the safe range by the node voltage deviation

The process of building an optimization model of recovery is as follows.

이며, 즉, 각 직류시스템 시간 스탭별 유효 파워 회복량이다.the determining variable

, that is, the effective power recovery amount for each DC system time step.

The amount of DC power recovery for each time step to be optimized is the maximum.

이며,

is,

The equations constraining the sensitivity of the node voltage to the effective power carried by direct current are

이며,

is,

The inequality of the DC power upper limit constraint and the node voltage safe range constraint is

이고,

ego,

는 직류로 수송하는 파워의 상한이며;

는 노드

의정격 전압이고

는 노드 전압의 안전 하한이다.In the formula,

is the upper limit of the power transported by direct current;

is the node

is the rated voltage

is the safe lower limit of the node voltage.

Furthermore, the optimization model of DC transport effective power recovery, which is constrained within the safe range by the node voltage deviation, finds an answer through the linear planning function of CPLEX, and the Get optimal recovery power. The calculation result is sent to the controller of each DC system to control the recovery of DC effective power.

In step (4), the construction process of the optimization model of the expansion amount of the reactive power compensator aiming at the square and minimization of the node voltage deviation value is as follows.

이며, 즉, 시간 스탭별 직류 파워 회복이 완성된 후의 노드별 무효파워보상장치 증설량이다.the determining variable

, that is, the amount of expansion of the reactive power compensation device for each node after DC power recovery for each time step is completed.

이며;The optimization goal is the square and minimum of the deviation values of the node voltages,

is;

이며;The equation constraining the sensitivity to the reactive power sent by the reactive power compensator is

is;

이다.The inequality of the upper limit of the capacity limit of the reactive power compensator is

am.

는 무효파워보상장치의 용량 상한이다.In the formula,

is the upper limit of the capacity of the reactive power compensation device.

Furthermore, the optimization model of the expansion amount of the reactive power compensator, which aims to square and minimize the value of the node voltage deviation, finds an answer through the linear planning function of CPLEX and Obtain the optimal amount of expansion so that the node voltage deviation caused by DC power recovery is minimized. Reactive power compensation is controlled by sending the calculation result to the reactive power compensation facility controller of each substation.

This embodiment takes the 4-DC infeed 39-node system shown in FIG. 3 as an example to further describe the specific implementation process of the present invention.

인 시각부터 회복을 시작하며 시간 스탭 길이는 5min 이다. 본 실례의 구체적인 구현과정은,The method of forming the power system of this embodiment is improved from the IEEE-39 node standard power system, and the power generation units of nodes 35, 36, 37 and 38 are modified to an in-feed DC system; The dotted line in Fig. 3 indicates a circuit or bus line that has not yet been restored; In the power recovery stage, the initial power of each DC system is set to 10% of the rated power,

The recovery starts from the time you are in, and the length of the time step is 5 minutes. The specific implementation process of this example is,

(1) forming a cross-DC system power flow equation by obtaining initial power grid information for each time step including node voltage, load power, generator power, DC control parameters, DC transport power and reactive power compensator input;

(2) Obtain the one-way equation of the AC-DC system power flow equation to obtain the power flow Jacobian matrix, extract and inverse a matrix for each block that reflects the influence of the node voltage on the reactive power, and calculate the sensitivity matrix of the node voltage to the reactive power and furthermore, obtaining a sensitivity matrix of the node voltage with respect to the effective power transported by direct current and a sensitivity matrix of the node voltage with respect to the reactive power transmitted by the reactive compensator;

(3) Build an optimization model of DC power recovery using the sensitivity matrix of node voltage for effective power transported by DC, and obtain the model using CPLEX to obtain the optimal power recovery amount for each DC system under the premise of voltage safety. sending to a DC rectification station controller to control power recovery according to an optimization result;

(4) Using the sensitivity matrix of the node voltage for the effective power sent by the reactive power compensator, an optimization model of the amount of expansion of the reactive power compensator is built, and the model is obtained using CPLEX to minimize the amount of voltage deviation caused by DC power recovery. obtaining an optimal expansion plan of the reactive power compensation device, sending it to each substation reactive power compensation controller, and controlling reactive power compensation according to the optimization result; includes

If all four DC system powers are not restored, the optimization control of the next time step is entered; When all four DC powers are recovered, the multi-phase DC system power recovery step is completed.

When setting node 16 as the backbone node of the embodiment system, after one-step operation, the voltage of node 16 is calculated using power current calculation software to reflect the overall voltage level of the system. 4 shows the voltage change of the node 16 in the multi-phase DC system power recovery process using the comprehensive control method according to the present invention. As shown in FIG. 4 , the node voltages lowered by the DC power recovery for each time step are all within the safe range, and after the reactive power control is performed, the node voltage is restored to a level close to the normal voltage again, resulting in the total power of the multi-phase DC system. Voltage safety in the recovery process is guaranteed, and the total time required for DC power recovery is 20 minutes. Figure 5 records the voltage change at node 16 in the power recovery process of the multi-phase DC system without using the comprehensive control method according to the present invention. In each DC system for each time step, 10% of the power is recovered and reactive power compensation is performed. Not timely control.

As shown in Fig. 5, since the comprehensive control method that guarantees voltage safety is not used, the system voltage level is also seriously lowered as the multi-phase DC system power is restored, posing a serious threat to the operating safety of the system; In addition, the total required time for DC power recovery reaches 40 minutes, which is longer than the total required time for DC power recovery of the comprehensive control method according to the present invention. Therefore, it is realized that the present invention has important guiding significance for the improvement of safety and high efficiency participating in the recovery of the multi-stage DC system.

Example 2

In one or multiple embodiments,

A device used to build a power flow equation of a AC-DC system based on the initial state for each time step;

a device used to obtain a sensitivity matrix of node voltages with respect to the effective power transmitted by the DC system, and a device used for obtaining a sensitivity matrix of node voltages with respect to the reactive power transmitted by the reactive compensator;

a device used to construct an optimization model of DC effective power recovery that is constrained within a safe range by the amount of deviation of all node voltages according to the sensitivity matrix of the node voltage with respect to the effective power transported by DC; A device used to obtain an optimal recovery amount of effective power for each DC system on the premise of voltage safety for each time step by obtaining a corresponding model;

A device used to construct an optimization model of the amount of expansion of the reactive power device that aims to square and minimize the amount of deviation of the node voltage based on the sensitivity matrix of the node voltage to the reactive power sent by the reactive power compensation device; A device used to obtain an optimal expansion amount for each invalid compensation device after DC power recovery is completed for each time step by obtaining a model, and to minimize the node voltage deviation caused by DC power recovery; It provides a comprehensive control system that guarantees the voltage stability of the multi-phase DC system power recovery step, characterized in that it comprises a.

In some other embodiments, a processor and a computer-readable storage medium are included, wherein the processor is used to implement each instruction; A computer-readable storage medium is used to store a plurality of instructions, the instructions being loaded by the processor, and a terminal suitable for executing the comprehensive control method for ensuring voltage stability in the multi-phase DC system power recovery step in Embodiment 1 reveal the device.

In some other embodiments, a plurality of commands are stored therein, the commands are loaded by the processor of the terminal device, and a computer suitable for executing a comprehensive control method for ensuring voltage stability in the multi-phase DC system power recovery step in Embodiment 1 A readable storage medium is disclosed.

Although the above description has described a specific embodiment of the present invention in combination with the drawings, it does not limit the protection scope of the present invention, and those skilled in the art to which the present invention pertains on the basis of the technical solution according to the present invention. It should be understood that various modifications or variations directly performed by technicians without creative labor still fall within the protection scope of the present invention.

Claims (10)

In the comprehensive control method for ensuring voltage stability in the multi-phase DC system power recovery step,
establishing a power flow equation of the AC-DC system based on the initial state for each time step;
obtaining a sensitivity matrix of the node voltage with respect to the effective power transmitted by the DC system and a sensitivity matrix of the node voltage with respect to the reactive power transmitted by the reactive compensation device;
According to the sensitivity matrix of the node voltage for the effective power transported by DC, an optimization model of DC effective power recovery that is constrained within a safe range by the amount of deviation of all node voltages is constructed, and the voltage safety is determined by time step by obtaining the model. obtaining an optimal recovery amount of effective power for each DC system on the premise;
Based on the sensitivity matrix of the node voltage to the reactive power sent by the reactive power compensator, an optimization model of the amount of expansion of the reactive power device aimed at squaring and minimizing the amount of deviation of the node voltage is constructed, and the time step is obtained by obtaining the model In the multi-phase DC system power recovery step, comprising: obtaining an optimal expansion amount for each invalid compensation device after each DC power recovery is completed, so that the node voltage deviation caused by DC power recovery is minimized; Comprehensive control method that guarantees voltage stability. According to claim 1,
The process of constructing the power flow equation of the AC-DC system is specifically,
Alternating Generator Unit Node

Based on the active and reactive powers sent to the node,

The active power and reactive power of the load consumption of

constructing an AC system power flow equation from the relationship between the active power and the reactive power of ;
Constructing an operating equation of the DC system based on the relationship between each of the active power and reactive power transported by DC and the voltage amplitude and phase angle of the commutation bus;
In the multiphase DC system power recovery step, characterized in that it includes; the rectification bus point establishes a power balance equation based on the AC system power flow equation and the operation equation of the DC system to obtain the AC-DC system power flow equation Comprehensive control method that guarantees voltage stability. According to claim 1,
Obtaining the sensitivity matrix of the node voltage to the effective power carried by the DC system is specifically:
Finding the one-way using the amplitude and phase angle of the cross-DC power current equation for each node voltage and obtaining the Jacobian matrix of the cross-DC power flow system; extracting a matrix for each block that reflects the effect of the node voltage amplitude on the reactive power injected by the node from the Jacobian matrix, and inversely calculating it to obtain a sensitivity matrix of the node voltage to the reactive power injected by the node;
Based on the power coefficient of the DC inverter, the reactive power absorbed by the DC system is displayed as the active power transported by the DC system, and then it is substituted into the node voltage sensitivity matrix for the reactive power injected by the node and the DC system transported it. A comprehensive control method for ensuring voltage stability in the multi-phase DC system power recovery step, comprising: obtaining a sensitivity matrix of the node voltage with respect to the effective power. According to claim 1,
Obtaining the sensitivity matrix of the node voltage to the reactive power sent by the reactive power compensator is specifically,
By one-way the amplitude and phase angle of each node voltage using the AC-DC power flow equation, the power flow Jacobian matrix of the AC-DC system is obtained; From the Jacobian matrix, a matrix for each block that reflects the effect of the node voltage amplitude on the reactive power injected by the node is extracted and inversed, and the sensitivity matrix of the node voltage to the reactive power injected by the node, that is, the A comprehensive control method for ensuring voltage stability in the power recovery step of a multi-phase DC system, characterized in that it obtains a sensitivity matrix of the node voltage to reactive power. According to claim 1,
Constructing an optimization model of DC effective power recovery that is constrained within a safe range by the amount of voltage deviation of all nodes is specifically,
The power recovery amount for each time step of each DC system is taken as a determining variable; The optimization goal is to maximize the amount of DC effective power recovery per time step; Constrain the equation of the sensitivity of the node voltage to the effective power carrying in direct current to the equation; Composite that guarantees voltage stability in the multi-phase DC system power recovery stage, characterized by constructing an optimization model of DC effective power recovery by inequality restrictions on the amount of voltage deviation for each node within the safe range and the upper limit of DC system power recovery control method. According to claim 1,
Constructing an optimization model of the amount of expansion of reactive power devices aimed at the square and minimization of the node voltage deviation is specifically,
After completing the DC power recovery for each time step, the expansion amount of the reactive power compensator is used as a determining variable; Optimizing the square and minimum of the node voltage deviation caused by the DC power recovery as the optimization goal; constraining the sensitivity equation of the node voltage to the reactive power sent by the reactive power compensating device by an equation; A comprehensive control method that guarantees voltage stability in the power recovery stage of a multi-phase DC system, characterized in that the upper limit of the reactive power sent by the reactive power compensator is constrained in an inequality manner and an optimization model of the amount of expansion of the reactive power compensator is established. According to claim 1,
Comprehensive control method to ensure voltage stability in the multi-phase DC system power recovery step, characterized in that both the optimization model of the effective power recovery and the optimization model of the expansion amount of the reactive power compensation device are implemented by the linear planning function of CPLEX In the comprehensive control system that guarantees voltage stability in the multi-phase DC system power recovery stage,
A device used to build the power flow equation of a AC-DC system based on the initial state per time step;
a device used to obtain a sensitivity matrix of the node voltage to the effective power transmitted by the DC system, and a device used to obtain a sensitivity matrix of the node voltage to the reactive power transmitted by the reactive compensator;
a device used to construct an optimization model of DC effective power recovery that is constrained within a safe range by the amount of deviation of all node voltages according to the sensitivity matrix of the node voltage with respect to the effective power transported by DC; A device used to obtain an optimal recovery amount of effective power for each DC system on the premise of voltage safety for each time step by obtaining a corresponding model;
A device used to construct an optimization model of the expansion amount of the reactive power device that aims to square and minimize the amount of deviation of the node voltage based on the sensitivity matrix of the node voltage to the reactive power sent by the reactive power compensation device; A device used to obtain an optimal expansion amount for each invalid compensation device after DC power recovery for each time step is completed by obtaining a model, and to minimize the node voltage deviation caused by DC power recovery; characterized by comprising: A comprehensive control system that guarantees voltage stability in the power recovery stage of a multi-phase DC system. In the terminal device,
a processor and a computer readable storage medium, wherein the processor is used to implement each instruction; The computer readable storage medium is used to store a plurality of instructions, the instructions being loaded by the processor to ensure voltage stability in the multiphase direct current system power recovery step according to any one of claims 1 to 7; A terminal device suitable for executing a control method. A computer readable storage medium comprising:
A plurality of commands are stored, and the commands are loaded by the processor of the terminal device to execute the comprehensive control method for ensuring voltage stability in the multi-phase DC system power recovery step according to any one of claims 1 to 7 A computer readable storage medium characterized in that it is suitable.

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