节点文献

油田电网谐波检测与APF控制技术的研究

The Harmonic Detection of Oilfield Power Network and the Research of the APF’s Control Technology

【作者】 付光杰

【导师】 段玉波;

【作者基本信息】 大庆石油学院 , 油气储运工程, 2008, 博士

【摘要】 为了提高原油产量和综合经济效益,在油田配电系统中投入大量电力半导体装置,日益增多的用电节能系统给油田电网注入大量谐波,污染电网。“电力污染”问题不仅给油田生产造成很大的损失,还危及电网的运行安全。有源电力滤波器(APF)是抑制谐波、提高电网供电质量的有效方法。有源电力滤波器中畸变电流的检测与控制方法不仅是决定其补偿性能的关键因素,而且也影响到有源电力滤波器的应用范围。本文主要研究有源电力滤波器畸变电流检测和控制的新方法,以适应现代电力系统的多变性及有源电力滤波器不同应用的要求。首先,在对电力谐波的产生、危害及目前最新的治理措施进行必要的论述和分析的基础上,对四相和三相APF进行分析比较,确定了本系统的主电路为三相四线结构;对主电路分析计算确定主开关元件,对主开关元件的保护电路进行详细分析,给出具体保护电路,并对缓冲保护元件进行设计;分析了APF主电路的开关频率,并讨论了参数之间的相互关联;提出了基于分量法的电容电压波动的估算方法,导出直流侧电容容量与电容电压纹波的关系,基于这个关系,可以对有源电力滤波器直流侧电容值进行设计,并通过仿真验证其正确性;同时基于电流跟踪性能要求对电感值进行设计。其次,总结了当前主流的谐波检测方法,提出了一种基于小波神经网络的谐波检测方法。从谐波电流检测的实时性和准确性来考虑,采用基于噪声抵消原理的自适应检测法与神经网络相结合的方法,提出了基于噪声抵消原理的免疫算法的径向基函数神经网络谐波检测方法,通过仿真实验证明了该方法具有学习收敛速度快、精度高的特点,能实时检测出电网的谐波电流。最后,对APF的控制方法进行研究,通过对空间电压矢量PWM控制进行具体分析,对APF的空间矢量调制电流跟踪控制方法进行了具体分析,通过仿真验证该算法的正确性和有效性;综合考虑APF的电路参数、开关频率改变和直流侧电压的波动的适应性,提出矢量单周控制方法。通过仿真结果证明,采用这种控制方式的APF能够动态地对电流谐波和无功进行有效补偿,采用该控制方法的APF具有简单、可靠、鲁棒性好、控制精度高、效率高等优点。通过本文的研究工作,对油田电网谐波抑制装置的实验系统的开发起到一定的指导和参考作用。

【Abstract】 In order to increase the crude oil output and overall economic efficiency, we put in a lot of power-semiconductor devices in the oilfield distribution system. A growing number of energy-saving systems have caused the large harmonics to pollute the oilfield power networks. "Power Pollution" can not only cause a great loss of oil production, but also endanger the safe operation of power networks. Active Power Filter (APF) is an effective way for suppressing harmonics and improving the quality of power supply. The measurements and control methods of distorted current in the APF are not only the key factors which determine the compensation performances, but also affecting the application scope of APF. This paper mainly studies the new ways of measuring and controlling the distorted current of APF, to adapt to the modern power system’s variability and the different applicational requirements for APF.First, on the basis of the necessary expositions and analysis of power harmonics generation, hazard and the current control measures, the paper analyzes and compares the four-phase and three-phase APF, and establishes the main circuit structure which is three-phase four-wire style of this system; to identify the main switch components by analyzing and computing the main circuit; to identify the specific protection circuit and design the buffer protection components by analyzing the protection circuits of the main switch components in detail; the paper analyses the switch frequency of main circuit of APF and discusses the interrelationship among many parameters; the paper proposes the estimated method of the capacitor voltage fluctuations based on the component method, and gets the relationship between the DC capacity and the fluctuation of capacitance voltage, we can design the value of the APF’s DC capacitor based on this relationship, and verify its accuracy by simulation; at the same time, design the value of the inductance based on the current tracking performances.Secondly, this paper summarizes the current main methods of harmonic detection and puts forward a harmonic detection method based on wavelet neural network (WNN). Considering the real-time quality and accuracy of the harmonic current detection, this paper proposes a harmonic detection method of RBF neural network based on immune algorithm according to the principle of noise canceling, using neural network combined with adaptive detection algorithms on the basis of noise canceling. Simulation experiments show that RBF neural network based on immune algorithm has the characteristics of high convergence rate and accuracy, and power system harmonic current can be detected in real-time.Finally, the paper studies the control methods of APF. Through the specific analysis of the space vector PWM control, the current tracking control method based on space vector modulation is specifically analyzed, and then the simulation tests show the correctness and effectiveness of the algorithm; considering the adaptability of the changes of APF’s circuit parameters and switch frequency, and the fluctuations of DC side voltage comprehensively, the paper proposes the vector one-cycle control method. The simulation results show that adopting this control method the APF can dynamically compensate the current harmonic and reactive power effectively, and it has a lot of advantages, such as simple, reliable, robust, high control precision, and high efficiency.These researches in a certain extent play a guiding and reference role in developing the experimental system for devices of harmonic suppression of oilfield power network.

节点文献中: