CN104050533B - Electric power system wind power plant fair-share scheduling method based on minimum wind curtailment control - Google Patents

Abstract

The invention relates to an electric power system wind power plant fair-share scheduling method based on minimum wind curtailment control, and belongs to the technical field of operation and controlling for new energy to be access into a power system. The method comprises the steps that according to the acceptable capacity of a current power grid to wind power generation, when the power grid can continuously accept wind power generation, recovery control is started, and the active power of wind power plants which are low in load rate and have wind curtailment is preferentially improved; when wind curtailment needs to be conducted on the power grid, wind curtailment is started, and the active power of the wind power plants which are high in load rate and have the wind curtailment condition is preferentially reduced; when the adjusting demand of power grid wind generation is zero, adjusting control is started, the active power of the wind power plants which are high in load rate is lowered, the active power of the wind power plants with the low load rate is improved, and the force output load rate deviation of all controlled wind power plants is made to be close to zero. The electric power system wind power plant fair-share scheduling method can be integrated in a wind power generation active control main station system operating in a scheduling center, it is guaranteed that a power grid is provided with sufficient backspin safe space, and fair-share scheduling between all the wind power plants is considered.

Description

A fair scheduling method for wind farms in power systems based on minimum wind curtailment control

technical field

The invention relates to a fair scheduling method for wind farms in a power system based on minimum wind curtailment control, and belongs to the technical field of operation and control of new energy access to power systems.

Background technique

The strong randomness of wind resources, difficulty in forecasting, and anti-peak regulation make the active power dispatching and control of the power grid more difficult. How to maximize the utilization of wind power resources and absorb as much wind power as possible on the premise of ensuring the safety of the power grid has become one of the common challenges faced by the power grids where all wind power bases are located. At present, the industry has conducted a lot of research on the active power dispatching control after the wind power generation is connected, and obtained a series of research and application results. The actual field operation experience shows that the introduction of minute-level fast wind power dispatching real-time control in the active power dispatching control system can play a significant role in ensuring the safety of the power grid and reducing the loss of wind curtailment.

At present, the engineering site mainly adopts the heuristic manual control method to control the active power of the wind farm, that is, when there is a security problem in the power grid and the active power of the wind farm needs to be reduced, the operating personnel can directly cut off one or more wind farms or reduce the The amount of abandoned wind is evenly distributed to each wind farm. This method relies on the experience of operators, and it is difficult to guarantee the fairness of dispatching. At the same time, when the security of the power grid is not limited and there is room for wind power acceptance, the manual control method cannot restore the active power of the wind farm in time, resulting in unnecessary wind curtailment.

Contents of the invention

The purpose of the present invention is to propose a fair scheduling method for wind farms in power systems based on minimum wind curtailment control to overcome the deficiencies of the prior art, so as to adapt to the rapid fluctuation of current wind power generation and the requirements of power grid security, minimum wind curtailment and fair dispatch Multiple control needs.

The method for fair dispatching of wind farms in power systems based on minimum wind curtailment control proposed by the present invention includes the following steps:

(1) From the data collection and monitoring control system of the power grid, collect the real-time down-spinning standby of the automatic power generation control unit of the current power grid, and the active power deviation of the connection line between the wind farm and the power grid, and obtain the wind farm that the power grid can accept from the power grid dispatching center active power Collect the real-time active power p ^w and the lower limit of active power of each wind farm connected to the grid Estimated maximum active power Real-time active power p ^s and active power upper limit of the connection line section between each wind farm and the grid

(2) Obtain the active power sensitivity S ^SW of each wind farm to the connection line section between the wind farm and the grid from the grid dispatching center;

(3) Establish the objective function of the fair dispatch method for wind farms in power systems based on minimum wind curtailment control, as follows:

Where: Ω ^w is the set of all wind farms connected to the grid, is the active power of the wind farm that can be accepted by the grid, is the wind curtailment adjustment amount of the i-th wind farm, r _i ^w is the load deviation rate of the i-th wind farm, W ^p and W ^r are weight coefficients respectively, W ^p >W ^r , W ^p takes the value of 10.0, and W ^r The value is 0.01;

(4) Set constraints for the fair dispatch method of wind farms in power systems based on minimum wind curtailment control, including:

(4-1) Real-time active power, lower limit of active power, and wind curtailment adjustment amount of the i-th wind farm and the estimated maximum active power satisfy the following relationship:

(4-2) The real-time active power of the connecting line section between the i-th wind farm and the grid active power upper limit The relationship between the sensitivity S ^SW and the adjustment amount of abandoned wind Δp ^w,o satisfies the following formula:

(4-3) The adjusted amount of abandoned wind of all wind farms in the grid satisfies the following relationship:

Among them, Ω ^w is the set of all wind farms connected to the grid, is the active power of the wind farm that can be accepted by the grid, is the real-time active power of the i-th wind farm, is the lower limit of the active power of the i-th wind farm;

(4-4) Set the directional constraint of wind power generation active power adjustment, when the active power of the wind farm that can be accepted by the grid Make i∈Ω ^w , when when i∈Ω ^w ;

(5) solving the quadratic programming mathematical model of above-mentioned step (3) and step (4) by interior point method, obtains wind farm active power adjustment amount;

(6) Control the wind farm with the above-mentioned active power adjustment amount of the wind farm, and realize the fair dispatch of wind farms based on the power system with the goal of minimizing wind curtailment control.

The characteristics and effects of the fair scheduling method for wind farms in power systems based on the minimum wind curtailment control proposed by the present invention are: according to the ability of the current power grid to accommodate wind power generation, when the power grid can continue to accommodate wind power generation, the recovery control is started, Give priority to increasing the active power of wind farms with low load rate and wind curtailment; when the grid needs to curtail wind, start the wind curtailment control, and give priority to reducing the active power of wind farms with high load rate and wind curtailment conditions; when the grid wind power regulation demand is At zero time, the adjustment control is started to reduce the active power of wind farms with high load rate and increase the active power of wind farms with low load rate, so that the deviation of active power load rate of each controlled wind farm is close to zero. This method can be integrated in the wind power generation active power control master station system operated by the dispatching center, so that the system can implement the most appropriate control strategy in real time according to the operation status of wind power generation and power grid, and ensure that the power grid has enough safety space for down-spinning , and the active power of the connecting line section between the wind farm and the power grid is safe, and the fair dispatch among the wind farms is taken into account.

detailed description

The method for fair dispatching of wind farms in power systems based on minimum wind curtailment control proposed by the present invention includes the following steps:

(1) From the data collection and monitoring control system of the power grid, collect the real-time down-spinning standby of the automatic power generation control unit of the current power grid, and the active power deviation of the connection line between the wind farm and the power grid, and obtain the wind farm that the power grid can accept from the power grid dispatching center active power Collect the real-time active power p ^w and the lower limit of active power of each wind farm connected to the grid Estimated maximum active power Real-time active power p ^s and active power upper limit of the connection line section between each wind farm and the grid

(2) Obtain the active power sensitivity S ^SW of each wind farm to the connection line section between the wind farm and the grid from the grid dispatching center;

(3) Establish the objective function of the fair dispatch method for wind farms in power systems based on minimum wind curtailment control, as follows:

Where: Ω ^w is the set of all wind farms connected to the grid, is the active power of the wind farm that can be accepted by the grid, is the wind curtailment adjustment amount of the i-th wind farm, r _i ^w is the load deviation rate of the i-th wind farm, which is used to represent the deviation between the load rate of each wind farm and the average load rate, and in the objective function To promote wind curtailment control to maximize the use of the grid to absorb wind power generation capacity and reduce wind farm curtailment, the objective function To promote the development of each wind farm in the direction of a more balanced active power, that is, the load rate deviation is close to zero, and W ^p and W ^r are weight coefficients respectively. In order to optimize and ensure the minimum wind curtailment, generally W ^p >W ^r . In practical applications, W ^p takes a value of 10.0, and W ^r takes a value of 0.01;

(4) Set constraints for the fair dispatch method of wind farms in power systems based on minimum wind curtailment control, including:

(4-1) Real-time active power, lower limit of active power, and wind curtailment adjustment amount of the i-th wind farm and the estimated maximum active power satisfies the following relationship: the active power of the wind farm is guaranteed to be between its minimum output and its estimated maximum output after over-limit correction control.

(4-2) The real-time active power of the connecting line section between the i-th wind farm and the grid active power upper limit The relationship between the sensitivity S ^SW and the wind curtailment adjustment Δp ^w,o satisfies the following formula: to ensure that the active power of the connecting line section between each wind farm and the grid is less than the upper limit of the active power after the over-limit correction control, where The maximum active power of the connecting line section between the wind farm and the grid, which is mainly limited by grid stability constraints,

(4-3) The adjusted amount of abandoned wind of all wind farms in the grid satisfies the following relationship:

Among them, Ω ^w is the set of all wind farms connected to the grid, is the active power of the wind farm that can be accepted by the grid, is the real-time active power of the i-th wind farm, is the lower limit of the active power of the i-th wind farm. The total wind curtailment adjustment amount is less than the constraint of the admissible wind power generation capacity, so as to avoid the frequency security problem of the power grid caused by the excessive active power of wind power generation, that is, the AGC unit has insufficient spinning equipment or the real-time active power value of the tie line deviates too much from the plan;

(4-4) Set the directional constraint of wind power generation active power adjustment, when the active power of the wind farm that can be accepted by the grid Make i∈Ω ^w , when when i∈Ω ^w ; this constraint prevents the adjustment amount of the curtailed wind from being in the opposite direction of the control target (for example, when the wind curtailment is required, an unreasonable instruction to increase the active output of a certain wind farm is generated).

(5) Solve the quadratic programming mathematical model of the above step (3) and step (4) by the interior point method, and obtain the active power adjustment amount of the wind farm with the goal of minimizing wind curtailment and taking into account the fair dispatch between wind farms;

(6) Control the wind farm with the above-mentioned active power adjustment amount of the wind farm, and realize the fair dispatch of wind farms based on the power system with the goal of minimizing wind curtailment control.

In the method for fair dispatching of wind farms in a power system based on minimum wind curtailment control proposed by the present invention, the automatic power generation control unit refers to the power generation unit participating in the automatic power generation control in the power grid. Automatic Generation Control (AGC) is a kind of power system active power adjustment and frequency control. AGC is one of the main contents of power system dispatch automation. It uses the dispatch center side monitoring computer, telecontrol channel, generator set automation device, etc. The closed-loop control system consists of monitoring and adjusting the frequency of the power system to control the output of the generator.

The automatic power generation control unit down-spinning involved in the method of the present invention is used to represent the maximum down-adjustable space of the active power of the unit. Let the current active power of unit i be The lower limit of active power is Then the active power of unit i is under standby is defined as:

The wind power station load deviation rate r _i ^w involved in the method of the present invention is used to characterize the deviation between the load rate and the average load rate of each wind power station, and satisfies the following relationship:

in is the average load rate of the wind power station, which is introduced into the wind power station in order to fully mobilize the enthusiasm of each wind power station to track the dispatching instructions of the control center, and is used as the basis for the fair dispatch of wind power generation, and satisfies the following relationship:

Among them, Ω ^w is the set of all controlled wind power stations, is the predicted maximum output value of the i-th wind power station sent by the wind power station. c ^w is the evaluation scoring index of wind power plants, which is used to quantitatively describe the degree of friendly access of wind power plants to the grid. It is mainly determined manually by dispatchers and updated periodically (monthly/ ^weekly ).

Claims (1)

1. A method for fair dispatching of electric power system wind farms based on minimum abandoned wind control, characterized in that the method comprises the following steps: (1) From the data collection and monitoring control system of the power grid, collect the real-time down-spinning standby of the automatic power generation control unit of the current power grid, and the active power deviation of the connection line between the wind farm and the power grid, and obtain the wind farm that the power grid can accept from the power grid dispatching center active power Collect the real-time active power p ^w , the lower limit of active power p ^w , and the estimated maximum active power of each wind farm connected to the grid Real-time active power p ^s and active power upper limit of the connection line section between each wind farm and the grid (2) Obtain the active power sensitivity S ^SW of each wind farm to the connection line section between the wind farm and the grid from the grid dispatching center; (3) Establish the objective function of the fair dispatch method for wind farms in power systems based on minimum wind curtailment control, as follows: $\underset{{\mathrm{<span\; class="notranslate">\; \&Delta;p</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; w</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; o</span>}}}{\mathrm{<span\; class="notranslate">\; m</span>}\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; W</span>}}^{\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; \&Delta;p</span>}}_{\mathrm{<span\; class="notranslate">\; w</span>}\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; d</span>}}^{\mathrm{<span\; class="notranslate">\; c</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; -</span>\underset{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; \&Element;</span>{\mathrm{<span\; class="notranslate">\; \&Omega;</span>}}^{\mathrm{<span\; class="notranslate">\; w</span>}}}{<span\; class="notranslate">\; \&Sigma;</span>}{\mathrm{<span\; class="notranslate">\; \&Delta;p</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; w</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; o</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; W</span>}}^{\mathrm{<span\; class="notranslate">\; r</span>}}<span\; class="notranslate">\; \&CenterDot;</span>\underset{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; \&Element;</span>{\mathrm{<span\; class="notranslate">\; \&Omega;</span>}}^{\mathrm{<span\; class="notranslate">\; w</span>}}}{<span\; class="notranslate">\; \&Sigma;</span>}{<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; w</span>}}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>$ Where: Ω ^w is the set of all wind farms connected to the grid, is the active power of the wind farm that can be accepted by the grid, is the wind curtailment adjustment amount of the i-th wind farm, r _i ^w is the load deviation rate of the i-th wind farm, W ^p and W ^r are weight coefficients respectively, W ^p > W ^r , W ^p takes a value of 10.0, and W ^r The value is 0.01; (4) Set constraints for the fair dispatch method of wind farms in power systems based on minimum wind curtailment control, including: (4-1) Real-time active power, lower limit of active power, and wind curtailment adjustment amount of the i-th wind farm and the estimated maximum active power satisfy the following relationship: ${\underset{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; p</span>}}}_{\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; w</span>}}<span\; class="notranslate">\; \&le;</span>{\mathrm{<span\; class="notranslate">\; p</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; w</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&Delta;p</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; w</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; o</span>}}<span\; class="notranslate">\; \&le;</span>{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; p</span>}}}_{\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; w</span>}}<span\; class="notranslate">\; ;</span>$ (4-2) The real-time active power of the connecting line section between the i-th wind farm and the grid active power upper limit The relationship between the sensitivity S ^SW and the adjustment amount of abandoned wind Δp ^w,o satisfies the following formula: ${\mathrm{<span\; class="notranslate">\; p</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; S</span>}}^{\mathrm{<span\; class="notranslate">\; S</span>}\mathrm{<span\; class="notranslate">\; W</span>}}{\mathrm{<span\; class="notranslate">\; \&Delta;p</span>}}^{\mathrm{<span\; class="notranslate">\; w</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; o</span>}}<span\; class="notranslate">\; \&le;</span>{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; p</span>}}}_{\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; ;</span>$ (4-3) The adjusted amount of abandoned wind of all wind farms in the grid satisfies the following relationship: $\underset{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; \&Element;</span>{\mathrm{<span\; class="notranslate">\; \&Omega;</span>}}^{\mathrm{<span\; class="notranslate">\; w</span>}}}{<span\; class="notranslate">\; \&Sigma;</span>}{\mathrm{<span\; class="notranslate">\; \&Delta;p</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; w</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; o</span>}}<span\; class="notranslate">\; \&le;</span>\mathrm{<span\; class="notranslate">\; m</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; \{</span>{\mathrm{<span\; class="notranslate">\; \&Delta;p</span>}}_{\mathrm{<span\; class="notranslate">\; w</span>}\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; d</span>}}^{\mathrm{<span\; class="notranslate">\; c</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; ,</span><span\; class="notranslate">\; -</span>\underset{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; \&Element;</span>{\mathrm{<span\; class="notranslate">\; \&Omega;</span>}}^{\mathrm{<span\; class="notranslate">\; w</span>}}}{<span\; class="notranslate">\; \&Sigma;</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; p</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; w</span>}}<span\; class="notranslate">\; -</span>{\underset{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; p</span>}}}_{\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; w</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \}</span>$ Among them, Ω ^w is the set of all wind farms connected to the grid, is the active power of the wind farm that can be accepted by the grid, is the real-time active power of the i-th wind farm, is the lower limit of the active power of the i-th wind farm; (4-4) Set the directional constraint of wind power generation active power adjustment, when the active power of the wind farm that can be accepted by the grid Make i∈Ω ^w , when when i∈Ω ^w ; (5) Solve the mathematical model of the above-mentioned step (3) and step (4) based on the minimum curtailment control wind farm fair dispatching method of the power system by the interior point method, and obtain the wind farm active power adjustment amount; (6) Control the wind farm with the above-mentioned active power adjustment amount of the wind farm, and realize the fair dispatch of the wind farm based on the power system with the goal of minimizing wind curtailment control.