【作者】 张颖；

【导师】 卫志农；

【作者基本信息】 河海大学 ， 电力系统及其自动化， 2006， 硕士

【摘要】 灵活交流输电系统(FACTS)技术以及高压直流输电(HVDC)技术在电力系统中的应用,实现了系统的安全、稳定、灵活运行,提高了整个电力系统的运行性能,同时也促进了对带有开关元件的电力系统分析方法的研究。 由于电力系统的庞大和复杂性以及计算规模和时间的限制,不可能对系统中所有的这些开关器件采用详细的包含阈过程的细致的电磁暂态仿真模型,而准稳态模型不能反映电力电子装置内部的瞬变电压电流特性,因而对于研究器件内部故障过程、控制方法和对整个系统行为的影响具有很大的局限性。 针对上述问题,本文以FACTS家族中最具代表性的统一潮流控制器(UPFC)装置作为研究对象,从两方面着手。一方面,研究了UPFC的各种模型,在详细时域模型的基础上,建立UPFC装置的非线性、大信号、时不变的动态相量模型,文中通过仿真算例比较证明,动态相量模型既可以反映出模型的主要动态特性,保证准确度,又比详细时域模型简单易用;另一方面,针对系统不同元件的特性,考虑能进行仿真电磁暂态过程和机电暂态过程的混合仿真算法,该算法既考虑了开关器件的动态特性,又保证了仿真的快速有效。 综合这两个方面,本文提出了基于UPFC时变动态相量模型的混合仿真算法,在传统的电力系统电磁暂态和机电暂态混合仿真算法的基础上,以基频下的UPFC时变动态相量模型代替详细时域模型,则EMTP仿真转化为DPP(动态相量程序)仿真,这种模型的仿真可以采用较大的积分步长,其时不变特性大大简化了计算,并且采用基频下的时变动态相量模型无须以曲线拟合的方式求取基频量。最后通过仿真算例与传统混合仿真算法比较,验证了文中提出的方法的仿真速度及精度。更多还原

【Abstract】 It is implemented that power system operates safely, stably and neatly with the application of FACTS and HVDC devices. Meanwhile, the performance of the whole system is improved and the research of analytical method of the system has a practical meaning.Because electro-magnetic transient simulation approach has the disadvantage of high computational burden and relatively low efficiency, it is impossible to simulate all switch devices in detail. On the other hand, in transient stability simulation, the rapid transient response of switch devices can not be reflected, with the result that it is limited to analyze the internal fault of device, controlling method and the influence to the whole system.Therefore, the paper selects UPFC as the subject. On the one hand, model of UPFC is studied. As the middle models between EMTP model and TSP model, the dynamic phasor model of UPFC is built. Simulation results testify the veracity and effectiveness of the dynamic phasor model. On the other hand, hybrid simulation algorithm is considered to simulate the rapid transient response of switch devices at the same time to ensure the efficiency of the method.A new hybrid simulation algorithm is introduced to handle the interface between the UPFC and power network. Based on the tradition hybrid simulation, dynamic phasor method in modeling UPFC is used instead of detailed system. As a result, the new algorithm adopts long integration step and simplifies the calculation. It also passes over the process of curve fitting. Finally, compared with the tradition hybrid method, simulation results demonstrate the effectiveness of the proposed algorithm.更多还原