【作者】 常晓；

【导师】 王奔；

【作者基本信息】 西南交通大学 ， 电力系统及其自动化， 2013， 硕士

【摘要】 近年来,随着电力用户对电能质量要求的不断提高,许多国家针对统一电能质量控制器(UPQC)的理论研究和的试验研究都在不断增强。UPQC由串联变流器和并联变流器组合而成,它可以对畸变波形进行补偿、使动态电压快速恢复,具有统一实现多重电能质量调节的功能。本文着重研究UPQC的综合补偿检测方法和非线性控制策略。在对UPQC串、并联侧变流器补偿方法分别进行研究的基础上,对基于dp0坐标变换的UPQC电压电流综合补偿检测方法进行了研究,该方法不需要利用锁相技术对三相电压进行锁相,避免了由锁相环节带来的检测误差。仿真结果表明,该方法很好的弥补了现有的UPQC检测方法的不足。UPQC在运行过程中是一个多变量、强耦合、非线性的动态系统,其控制方法有PI控制、双环解耦控制、模糊控制等,但是往往难以做到精确解耦控制。本文采用两种非线性控制策略来设计UPQC的控制器。第一种是状态反馈精确线性化与变结构控制相结合的控制策略。基于dp0坐标系,建立了UPQC的非线性数学模型,利用状态反馈精确线性化理论把非线性系统解耦成伪线性系统,然后利用变结构控制来设计UPQC系统的控制器。第二种是无源控制策略。把dp0坐标系下UPQC的数学模型转化为欧拉-拉格朗日方程的形式,并验证系统的无源性。然后,利用无源控制理论设计UPQC串、并联侧的无源控制器。结合设计的UPQC综合补偿检测方法,在MATLAB软件中分别建立了UPQC系统的变结构控制模型和无源控制模型,对所设计的控制器的有效性进行验证。仿真结果表明,设计的这两种控制器可以很好的解决电压电流谐波、电压扰动以及负载扰动等电能质量问题,对系统外部扰动和内部电压、电流谐波等变化不敏感,具有很强的鲁棒性。更多还原

【Abstract】 With the continuous improvement of user’s request for power quality in recent years, many countries in the study of the theory and experimental research of the unified power quality controller (UPQC) have been enhanced. UPQC is composed of series inverter and shunt converter. It has multiple power quality regulation functions like the distortion waveform compensation and the dynamic voltage quick recovery.In this paper, we focus on the study of the synthesis compensating method and the nonlinear control strategy for UPQC. On the basis of the study of the compensating methods respectively to the UPQC series inverter and shunt converter, the voltage and current synthesis compensating method of the UPQC based on dqO coordinates transform is studied. The method does not need to lock the phase of three-phase voltage by phase lock technique, so as to avoid the error caused by phase lock. The simulation results show that this method is good enough to make up for the deficiency of the existing UPQC detection method.UPQC is a multivariable, nonlinear and strong coupling dynamic system in running process. Its control methods include PI control and double loop decoupling control, fuzzy control, etc. But these control methods are often difficult to achieve the precise decoupling control. In this paper, two strategies of nonlinear control are used to design the controller of UPQC. The first method is the exact linearization approach via state feedback combined with the variable structure control. The nonlinear mathematical model in dqO coordinates of UPQC is built and by using the exact linearization approach via state feedback of nonlinear control theory they are decoupled into a pseudo-linear system. Then, the controller of UPQC is designed by use of the variable structure control theory. The second method is Passivity-based control theory. The nonlinear mathematical model in dqO coordinates of UPQC is transform into Euler-Lagrange equation and the system passivity is verified. Then, the controller of the series and shunt converter of UPQC is designed by use of the passivity-based control theory.Combined with the synthesis compensating method of the UPQC, the variable structure control model and the Passivity-based control model are built respectively by using MATLAB software to verify the effectiveness of the designed controller. The simulation results show that the designed two kinds of controller can solve power quality problems such as the voltage and current harmonic, voltage and load disturbances etc. well. They are not sensitive to the changes of voltage and current harmonic and external disturbances. In other words, they have strong robustness.更多还原