A Simplification Method of Large-scale Unit Commitment Model Based on Boundary Method

doi:10.16182/j.issn1004731x.joss.23-1072

Abstract

Abstract:

As the scale of power grid expands, in the market environment, the variables and constraints in the security-constrained unit commitment (SCUC) model considering power grid security constraints increase significantly and the solvability of the model reduces. When the model scale is too large, even the existing commercial solvers cannot solve it. Aiming at the model rapid solving, from the perspective of reducing the number of model constraints, a linear constraint simplification method based on the boundary method is proposed. The proposed method can effectively reduce the model's size by eliminating the redundant linear constraints. The IEEE-39, WECC 179 and IEEE-118 test cases are utilized to carry out the day-ahead SCUC testing in a market environment. Comparing the solving speed before and after simplification, the proposed method can significantly improve the solving speed of the model.

Key words: security-constrained unit commitment(SCUC), solvability, boundary method, linear constraints, rapid solving

CLC Number:

TP391

Xu Yanping, Zhao Mingxin, Qin Xiaohui, He Keyou, Wu Xiaohan, Zhang Pei. A Simplification Method of Large-scale Unit Commitment Model Based on Boundary Method[J]. Journal of System Simulation, 2024, 36(2): 296-304.

Figures/Tables 13

Fig. 1

Table 1

Model scale

连续变量数量	$∑ i ∈ G e n (T S e g, i) N S e g$
整数变量数量	$3 N C o a l N S e g$
等式约束数量	$(N C o a l + 1) N S e g$
不等式约束数量 (不含网络安全约束)	$(5 N C o a l + N H y d r o + N W i n d + N S o l a r) N S e g$

Table 1

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规模	case39	case179
火电机组	7	21
水电机组	1	1
风电机组	1	3
光伏机组	1	4
线路	46	263

规模	case39	case179
连续变量	3 840	8 760
整数变量	504	1 512
等式约束	192	528
不等式约束 (不含网络安全约束)	912	2 712
网络安全约束数量	38 136	693 360
约束总量	43 584	706 872

算例	简化前	简化后
case39	38 136	18 459
case179	693 360	392 046

算例	简化前	简化后
case39	43 584	23 907
case179	706 872	395 286

算例		模型构建	求解	总时间
case39	简化前	6.059	3.600	9.659
case39	简化后	7.653	1.520	9.173
case179	简化前	262.565	201.226	463.791
case179	简化后	264.060	36.310	300.370