高铁牵引供电与区域电网相互作用及振荡机理研究

Loads of the Traction Power Supply System (TPSS) of High-Speed Railway (HSR) show characteristics of frequent impact, high power and large density. Series of abnormal and fault phenomenon appear frequently, such as resonance overvoltage and oscillation blockade, bringing brand new challenges to safety and reliability of the TPSS and even the whole Regional Power Grid (RPG). However, their principles are not clear at all. In this project, the theory of oscillation and interaction of the TPSS and the RPG is presented firstly from the aspect of coupling between the TPSS and the RPG. Through the establishing of dynamic coupled unified RPG-TPSS (catenary-train- reflux) model, interaction of the TPSS and the RPG is investigated. Principles of low frequency oscillation and higher harmonic resonance under interaction are researched so that the power outage and equipment burn-to-loss phenomenon caused by voltage oscillation blockade, resonance overvoltage and resonance overcurrent is explained. Voltage quality and catastrophe risk of the PRG operation are studied under the high power, unbalanced and frequent impact loads. The dynamic simulation and high frequency synchronous data acquisition system is designed and the data acquired by it is used to verify the principles. Combination of field test data, simulated analysis and theoretical modeling is brought in this project to comprehensively disclose the abnormal and fault oscillation phenomenon of the TPSS of HSR. The result and achievement play an important role in presenting suppress scheme and improving safety and reliability of the TPSS and the RPG.

高速铁路牵引供电负荷呈现频繁冲击、大功率、高密度等新特点，高铁运营以来频现系列异常或故障现象（如谐振过压、振荡封锁），给高铁甚至区域电网安全可靠带来了全新挑战，而目前该问题的产生机理尚不完全明确。项目首次从区域电网和牵引供电耦合的角度，提出高铁牵引供电系统与区域电网相互作用及振荡机理研究。通过建立区域电网-牵引供电（牵引网-动车-回流）动态耦合统一模型，考察区域电网与牵引供电的相互作用；研究相互作用下的低频振荡机理、高次谐波谐振机理，以解释电压振荡封锁、谐振过压、谐振过流等导致的供电中断或者设备故障等现象；研究大功率、不平衡、频繁冲击负荷作用下，区域电网运行的电压品质和灾变风险，通过开发动态仿真和同步高频数据采集系统获取数据以验证机理。项目采用实测数据、仿真分析、理论建模相结合的研究方法，有望全面揭示高铁牵引供电故障或振荡机理，对提出抑制方案、保障牵引供电和区域电网的安全可靠具有重要意义。

近年来，随着我国铁路运输的飞速发展，牵引供电系统特别是高速铁路牵引供电系统与区域电网耦合作用不断加强，同时其运行密度、容量及新型牵引负荷等特点引发的供电系统电能质量及稳定性问题不断加剧。基于此，本项目从区域电网和牵引供电系统耦合的角度出发，建立了区域电网-牵引供电系统动态耦合统一模型，重点关注耦合系统动态基波/谐波模型及用于稳定性分析的等效阻抗模型，考察了区域电网与牵引供电系统的相互作用；从枢纽牵引供电系统谐振特性、不同工况下的谐波特性及谐波综合治理等角度出发，系统揭示了区域电网与牵引供电系统相互作用下的枢纽系统谐波谐振机理；同时，从车牵系统动态潮流计算为出发点，开展了大规模频繁冲击复核下牵引供电系统综合电能质量分析，并开发设计了新型复杂牵引供电系统电能质量综合分析软件；以徐州枢纽牵引低频振荡实测为基础，通过时域仿真与小信号分析等手段系统揭示了牵引供电系统低频振荡的产生机理，并针对性的提出牵引主变扩容改造等抑制方案，并成功应用于现场；本课题组成功研制出区域电网——牵引供电系统高频同步采集系统，可以针对区域电网-牵引供电系统的复杂实际情况，进行针对不同现象的高频同步数据采集。至此，本项目实践了实测数据、仿真分析、理论建模相结合的分析方法，着眼于新形势下的牵引供电系统的新特点需求，对保障区域电网-牵引供电系统安全、稳定、可靠、高效运行，具有重要的理论与实际意义。