| Developing new energy is a great move for solving energy crisis andenvironmental pollution. Wind-solar-storage complementary power system takesfull advantage of complementary characteristics of wind and solar both in time andin space, and can provide rather stable output with the energy storage device'spower adjustment, and increase power grid 's acceptance to wind and solar. In thispaper, wind-solar-storage complementary power system was studied on two aspects,which were optimal sizing in the planning stage and analysis of short circuit currentcharacteristics and influence on relay protection of the tie-line in the operationstage.Firstly, Based on studying principle, structure, running mode ofwind-solar-storage complementary power system, an optimal sizing model for largescale complementary power system was established, which took pumped storagestation as the energy storage device, and took maximum total income in its lifecycle as optimization objective, and was constrained by complementarycharacteristics of wind and solar, resource utilization of wind and solar, outputtracking load curve and so on. Then a method named cyclic discretization onvariable step size was proposed to solve the model.Secondly, the transient simulation model of wind-solar-storage complementarypower system was built by using PSCAD software based on doubly-fed inductiongenerator, photovoltaic power system, pump-turbine transient models. The transientsimulation model's correctness was verified by studying its output characteristicswhen environmental factors such as wind speed, light intensity and so on changed.Lastly, short circuit current characteristics of wind-solar-storagecomplementary power system at the optimal size were studied under single-phaseground short, two-phase ground short,two-phase short and three-phase short basedon the transient simulation model of wind-solar-storage complementary powersystem. A detailed analysis of the influence of wind speed, light intensity, state ofpump-turbine, capacity configuration, state of crowbar on three-phase short circuitcurrent characteristics was given.This article compared and analyzed the differences between wind-solar-storagecomplementary power system and regular power on short circuit currentcharacteristics, and discussed the impact on the tie-line's three-sectionzero-sequence current protection and three-section distance protection whencomplementary power system was integrated to power system.The research results have guiding significance and practical value on the design, peace and steadiness operation of wind-solar-storage complementary powersystem.This research work is supported by the National High Technology Researchand Development of China (863Program)(NO.2011AA05A105). |
PDF Full Text Request