三相四桥臂并联APF的关键技术研究

发布时间：2018-03-01 06:04

本文关键词： 瞬时无功功率 APF 广义积分器 3D-SVPWM 比例谐振控制　出处：《郑州大学》2017年硕士论文　论文类型：学位论文

【摘要】：随着经济、科学技术的发展,电能作为新型清洁能源已经成为目前生产、生活中必不可少的部分。低压配电网的电能质量与系统的安全运行和人们的正常用电密切相关。然而,非线性电力电子设备的广泛使用以及分布式电源的大量接入给低压配电网引入了大量的谐波,严重降低了低压配电网的电能质量。因此,研究谐波的治理方法,提高配电网的电能质量,对电网和电力用户都具有深远的现实意义。本文讲述了与谐波相关的概念、产生原因、发展历程,由谐波给电网带来的危害引入,讨论了对其治理的措施,对APF做了详细分析;以并联APF为主要研究对象分析了其工作原理以及主电路拓扑,并由传统平均功率引出有源电力滤波器的理论基础——瞬时无功功率理论。谐波电流检测是APF的基础,本文在研究比较现阶段常用的谐波电流检测法之后,提出了一种基于广义积分器的改进qp-检测法。该方法能够在电网电压发生畸变或者不对称时实现谐波电流快速有效的检测,克服了传统qp-检测法的缺点,并且能够在无需锁相环的情况下通过调整增益系数实现谐波精准检测。谐波补偿控制策略是产生所需补偿电流的关键,对补偿效果起着决定性作用。本文通过对三角波比较、滞环电流控制等控制跟踪方法对比分析,结合谐振控制器良好的频率选择特性,提出改进的PR控制策略,并深入研究了其各参数与控制性能的关系,得出了控制器各参数的调试方法。仿真验证了改进PR控制器能够实现参考指令电流的无静差跟踪,同时响应速度满足要求。论文采用c-b-a坐标下SVPWM-3D,提高了直流电压利用率,降低了谐波含量,同时省去了α-β0-坐标下SVPWM-3D涉及的坐标转换问题,使计算更加简洁。文中详细阐述了c-b-a坐标下的三维空间矢量调制技术的工作原理及流程,并利用SimulinkMatlab/软件搭建了三相四桥臂APF仿真模型,仿真结果验证了所提方法能够在三相电压对称、畸变情况下实现系统谐波电流的快速、准确补偿。
[Abstract]:With the development of economy, science and technology, electric energy, as a new clean energy, has become an indispensable part of production and daily life. The power quality of low-voltage distribution network is closely related to the safe operation of the system and the normal power consumption of people. The widespread use of nonlinear power electronic equipment and the large amount of distributed power supply introduce a large number of harmonics into the low-voltage distribution network, which seriously reduces the power quality of the low-voltage distribution network. To improve the power quality of distribution network has far-reaching practical significance for both power grid and power users. This paper describes the concept of harmonics, the causes, the development process, and the harm brought by harmonic to the power network. The measures of its governance are discussed, and the APF is analyzed in detail, and its working principle and main circuit topology are analyzed with parallel APF as the main research object. The theory of instantaneous reactive power is derived from the traditional average power. Harmonic current detection is the basis of APF. An improved qp- detection method based on generalized integrator is proposed. This method can detect harmonic current quickly and effectively when the voltage is distorted or asymmetrical. It overcomes the shortcomings of the traditional qp- detection method. The harmonic compensation control strategy is the key to generate the required compensation current and plays a decisive role in the compensation effect. Based on the comparative analysis of hysteresis current control and other control tracking methods, combined with the good frequency selection characteristics of the resonant controller, an improved PR control strategy is proposed, and the relationship between the parameters and the control performance is deeply studied. The simulation results show that the improved PR controller can track the reference instruction current without static error, and the response speed meets the requirements. In this paper, SVPWM-3Din c-b-a coordinate is used to improve the utilization ratio of DC voltage. The harmonic content is reduced, and the coordinate conversion problem of SVPWM-3D in 伪-尾 0-coordinate is eliminated, which makes the calculation more concise. In this paper, the working principle and flow chart of three-dimensional space vector modulation technology in c-b-a coordinate are described in detail. The simulation model of three-phase four-arm APF is built by using Simulink Matlab / software. The simulation results show that the proposed method can compensate the harmonic current quickly and accurately under the condition of three-phase voltage symmetry and distortion.
【学位授予单位】：郑州大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM761

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