CN103972915B - A kind of optimum calculation of capacity method of energy-storage system for the peak load shifting of loading - Google Patents

Abstract

The present invention relates to a kind of optimum calculation of capacity method of energy-storage system for peak load shifting, belong to power system optimization computation technical field. Energy-storage system energy capacity Optimized model for the peak load shifting of loading of the inventive method model, reset the constraints for the energy-storage system energy capacity Optimized model of the peak load shifting of loading, adopt Quadratic Programming Solution method, solve quadratic programming model, obtain the optimal energy capacity of energy-storage system. The inventive method, can be based on historical load data, calculate the needed energy-storage system energy capacity of peak load reduction of specifying into meeting, and effectively alleviate the pressure that peak load causes electrical network, delay the upgrading of power system device.

Description

A kind of optimum calculation of capacity method of energy-storage system for the peak load shifting of loading

Technical field

The present invention relates to a kind of optimum calculation of capacity method of energy-storage system for the peak load shifting of loading, belong to power system optimumChange computing technique field.

Background technology

The fast development of national economy makes need for electricity sustainable growth, and in electrical network, peak load constantly increases. In order to ensure electricityThe safe and stable operation of power system, grid company need to strengthen investment send out to increase, defeated, the electric power in each link such as join, use establishStandby capacity. But, unreasonable due to power structure, the peak-valley difference of loading in electrical network is often very large. Negative for meeting peakLotus and the electrical network built, its equipment is not fully utilized in the time of low power consumption, thereby causes the asset utilization ratio of electrical network entiretyLowly, economic benefit is poor. Energy-storage system can absorb electric energy in the time of low power consumption, and in the time of peak of power consumption, discharges electric energy,Therefore can be used as " energy buffer ", in the transfer electrical energy between peak valley of loading, realize the function of peak load shifting. Therefore, at electricityEnergy-storage system is installed in net load is carried out to peak load shifting, can alleviate the pressure that peak load causes electrical network, delay electric powerSystem equipment upgrading.

The power capacity of energy-storage system need be depending on the demand of different application scene. For example, at Generation Side, the value of power capacityShould be relevant with the existing capacity of generator to peak load peak value; In power transmission and distribution side, the value of power capacity may with transmission powerThe maximum occurring is relevant to existing limit transmission power value. After determining power capacity, can be further according to historical loadData are determined the energy capacity of energy-storage system. Existing method comprises: (1) rate of load condensate is increased to specified scope as target,Energy storage system capacity under constant power output pattern is optimized; (2) to alleviate generator peak regulation pressure as target and economyIncome Maximum is target, determines energy storage power capacity according to the improvement level of load peak-valley difference, calculates afterwards optimum energy storage energyAmount capacity.

Summary of the invention

The object of the invention is to propose a kind of optimum calculation of capacity method of energy-storage system for the peak load shifting of loading, foundation is used forThe energy storage system capacity Optimized model of load peak load shifting, solves this Optimized model, to obtain the peak load shifting task time institute that loadsThe minimum energy storage energy capacity needing.

The energy-storage system optimal energy calculation of capacity method for the peak load shifting of loading that the present invention proposes, comprises the following steps:

(1) set up an energy-storage system energy capacity Optimized model for the peak load shifting of loading:

minf＝E_cap

Wherein, E_capFor energy-storage system rated energy capacity, f is optimization aim;

(2) set the constraints of the above-mentioned energy-storage system energy capacity Optimized model for the peak load shifting of loading as follows:

(2-1) the power constraint condition of energy-storage system is as follows:

${-P}_S^{\max }\≤P_S\left(k\right)\≤P_S^{\max },k=\mathrm{1,2},...,N$

Wherein, N is to the time hop count in energy-storage system energy capacity computing time, P_S(k) be energy storage system in k periodThe active power of system,Maximum active power during for energy storage system discharges,Maximum while charging for energy-storage systemActive power;

(2-2) the energy constraint condition of energy-storage system is as follows:

0.05E_cap≤E(k)≤0.95E_cap,k＝1,2,…,N

E(N)＝E(0)

E(k+1)＝E(k)-P_S(k)·Δt,k＝1,2,…,N

Wherein, the length that Δ t is each period, E (k) is the dump energy of energy-storage system in the time that k period finishes, E (0)For the dump energy of energy-storage system in the time that the 1st period starts;

(2-3) the peak load shifting constraints of energy-storage system is as follows:

$P_L\left(k\right)-P_S\left(k\right)\≤P_L^{\max }-P_S^{\max },k=\mathrm{1,2},...,N$

Wherein, P_L(k) be the load value of k period,For the maximum of N period internal loading;

(3) adopt Quadratic Programming Solution method, the quadratic programming model that solution procedure (1) and step (2) are set up, bagDraw together following steps:

(3-1), according to load peak load shifting demand, set the maximum active power of energy-storage system

(3-2) read the electrical network historical load data that multiple length is N period, according to multiple historical load data that read,Adopt Quadratic Programming Solution method, the quadratic programming model that solution procedure (1) and step (2) are set up respectively, obtains multipleOptimum energy-storage system energy capacity;

(3-3) from the energy-storage system energy capacity of above-mentioned multiple optimums, choose maximum, as the optimal energy of energy-storage systemCapacity.

The charge/discharge control method of battery energy storage system in the wind energy turbine set that the present invention proposes, its advantage is: can be negative based on historyLotus data, calculate the needed energy-storage system energy capacity of peak load reduction of specifying into meeting, and effectively alleviate peakThe pressure that Load on Electric Power Grid causes, delays the upgrading of power system device.

Brief description of the drawings

Fig. 1 is historical load curve synoptic diagram.

Fig. 2 has been energy-storage system optimal energy capacity schematic diagram after peak load load peak load shifting.

Specific implementation method

The energy-storage system optimal energy calculation of capacity method for the peak load shifting of loading that the present invention proposes, comprises the following steps:

(1) set up an energy-storage system energy capacity Optimized model for the peak load shifting of loading:

minf＝E_cap

Wherein, E_capFor energy-storage system rated energy capacity, f is optimization aim;

(2) set the constraints of the above-mentioned energy-storage system energy capacity Optimized model for the peak load shifting of loading as follows:

(2-1) the power constraint condition of energy-storage system is as follows:

${-P}_S^{\max }\≤P_S\left(k\right)\≤P_S^{\max },k=\mathrm{1,2},...,N$

Wherein, N is to the time hop count in energy-storage system energy capacity computing time, P_S(k) be energy storage system in k periodThe active power of system, when energy storage system discharges, active power is positive number, when charging, active power is negative,For energy storage systemMaximum active power when system electric discharge,Maximum active power while charging for energy-storage system;

(2-2) the energy constraint condition of energy-storage system is as follows:

0.05E_cap≤E(k)≤0.95E_cap,k＝1,2,…,N

E(N)＝E(0)

E(k+1)＝E(k)-P_S(k)·Δt,k＝1,2,…,N

Wherein, the length that Δ t is each period, E (k) is the dump energy of energy-storage system in the time that k period finishes, E (0)For the dump energy of energy-storage system in the time that the 1st period starts;

(2-3) the peak load shifting constraints of energy-storage system is as follows:

$P_L\left(k\right)-P_S\left(k\right)\≤P_L^{\max }-P_S^{\max },k=\mathrm{1,2},...,N$

Wherein, P_L(k) be the load value of k period,For the maximum of N period internal loading;

(3) adopt any one Quadratic Programming Solution method, the quadratic programming that solution procedure (1) and step (2) are set upModel, comprises the following steps:

(3-1), according to load peak load shifting demand, set the maximum active power of energy-storage system

(3-2) read the electrical network historical load data that multiple length is N period, according to multiple historical load data that read,Adopt any one Quadratic Programming Solution method, the quadratic programming model that solution procedure (1) and step (2) are set up respectively,Obtain the energy-storage system energy capacity of multiple optimums;

(3-3) from the energy-storage system energy capacity of above-mentioned multiple optimums, choose maximum, as the optimum energy of energy-storage systemAmount capacity.

In one embodiment of the present of invention, establish historical load data and come from December 30 1 day to 2013 December in 2013The bus load data that during day, certain transformer station records, as shown in Figure 1. The sample rate of load is 5 minutes/point, therefore oneIn it, have 288 points. In emulation, N gets 288, and single calculation interval length is 1 day, has 30 such metersCalculate the period. The maximum active power of energy-storage systemGet 4MW.

Quadratic programming model adopts the Quadratic Programming Solution function quadprog in numerical computations software Matlab to solve.

Fig. 2 has shown the optimum energy-storage system energy capacity result of cutting down required by task to completing 4MW peak load. From Fig. 2In visible, in order to complete the peak load shifting task of appointment, required energy-storage system energy capacity concentrates on 8MWh and 16MWhBetween. Wherein, maximum energy-storage system energy capacity is 11.17MWh, therefore finally determines that the optimum capacity of energy-storage system is11.17MWh。

Claims (1)

1. for an energy-storage system optimal energy calculation of capacity method for the peak load shifting of loading, it is characterized in that the method bagDraw together following steps:

(1) set up an energy-storage system energy capacity Optimized model for the peak load shifting of loading:

minf＝E_cap

Wherein, E_capFor energy-storage system rated energy capacity, f is optimization aim;

(2) set the constraints of the above-mentioned energy-storage system energy capacity Optimized model for the peak load shifting of loading as follows:

(2-1) the power constraint condition of energy-storage system is as follows:

$-P_S^{max}\≤P_S\left(k\right)\≤P_S^{max},k=1,2,...,N$

Wherein, N is to the time hop count in energy-storage system energy capacity computing time, P_S(k) be energy storage system in k periodThe active power of system,Maximum active power during for energy storage system discharges,Maximum while charging for energy-storage systemActive power;

(2-2) the energy constraint condition of energy-storage system is as follows:

0.05E_cap≤E(k)≤0.95E_cap,k＝1,2,…,N

E(N)＝E(0)

E(k+1)＝E(k)-P_S(k)·Δt,k＝1,2,…,N

Wherein, the length that Δ t is each period, E (k) is the dump energy of energy-storage system in the time that k period finishes, E (0)For the dump energy of energy-storage system in the time that the 1st period starts;

(2-3) the peak load shifting constraints of energy-storage system is as follows:

$P_L\left(k\right)-P_S\left(k\right)\≤P_L^{max}-P_S^{max},k=1,2,...,N$

Wherein, P_L(k) be the load value of k period,For the maximum of N period internal loading;

(3) adopt Quadratic Programming Solution method, the quadratic programming model that solution procedure (1) and step (2) are set up, bagDraw together following steps:

(3-1), according to load peak load shifting demand, set the maximum active power of energy-storage system

(3-2) read the electrical network historical load data that multiple length is N period, according to multiple historical load data that read,Adopt Quadratic Programming Solution method, the quadratic programming model that solution procedure (1) and step (2) are set up respectively, obtains multipleOptimum energy-storage system energy capacity;

(3-3) from the energy-storage system energy capacity of above-mentioned multiple optimums, choose maximum, as the optimal energy of energy-storage systemCapacity.