统一潮流控制器（UPFC）的控制方法研究

【作者】 张伟；

【导师】 彭永进；

【作者基本信息】 湖南大学 ， 电力电子与电力传动， 2003， 硕士

【摘要】 灵活交流输电系统(FACTS)是电力电子技术在电力交流输电系统中应用的一个重要方面，而统一潮流控制器(UPFC)能分别或同时调节输电线路的电压、阻抗和相角对线路的有功和无功潮流进行快速、有效地控制，是一种最灵活的FACTS控制器。论文介绍了UPFC的结构、工作原理和应用研究进展。 论文对UPFC的主要构成器件PWM变换器进行了研究，在PWM整流电路的直接电流控制方法中，采用了单神经元PID控制算法，与传统的PI控制方案仿真比较表明，该算法明显减少了直流电容电压在负载扰动时恢复到设定值的响应时间。对于电流滞环控制器，论文推导了其开关频率的计算公式，并依据制约开关频率的因素，提出了一种变环宽的滞环控制策略，比较固定环宽的控制方法，既相对稳定了开关频率，又提高了电流跟踪控制性能。 对于UPFC的模型及控制方法研究，论文运用矢量分析的方法，基于dqo同步旋转坐标系建立了UPFC串联侧的数学模型，对该模型采用了状态反馈解耦的方法，使有功和无功实现完全解耦，达到了理想的单独控制。为了满足工程上广泛应用的PI控制器的性能要求，又能克服一般PI控制器参数整定和调整困难的不足，论文提出了采用BP神经网络PI控制器分别对有功和无功进行控制的方案，使PI控制器的参数可以在线自动整定和调节，既提高了控制性能，又不必采用解耦环节而达到了减小有功和无功相互影响的效果。更多还原

【Abstract】 As the most flexible controller of the Flexible AC Transmission System (FACTS), a Unified Power Flow Controller(UPFC) can control transmission line impedance, voltage magnitude and phase angle either selectively or simultaneously in appropriate combinations and can also control independently the real and reactive power flow in a transmission circuit. This paper introduces the principle, performance and basic operating modes of the UPFC.The PWM inverter, one of the devices of the UPFC, is studied and the direct current control scheme of the PWM rectifier is discussed in this paper .A single neuron self-adaptive PID controller is designed in the scheme, which decreases the response time of DC voltage sharply when the load is changed. A hysteresis band current controller is analyzed and the calculating formulas about its switching frequency are deduced in the paper. According to the determinative factors of switching frequency, this paper presents a current control scheme with alterable hysteresis band, which reduces the range of switching frequency and improves the performance of the controlled current.By means of vector analysis, a mathematics model of the series part of the UPFC is deduced in dqo orthogonal co-ordinate within synchronously rotating reference frame. A state feedback decoupling method is applied in the model. Consequently, the real and reactive power can be controlled independently. Finally, a BP neuron network PI control scheme is presented for the mathematics model, and the parameter of the PI controller can be found automatically and adjusted online. Simulation results prove that the scheme improves the self-adaptive capability of PI controller, and lowers interaction of the real and reactive power.更多还原