【作者】 帅智康；

【导师】 罗安；

【作者基本信息】 湖南大学 ， 电气工程， 2011， 博士

【摘要】 电能是国民经济和人民生活的命脉,随着非线性负载的大量增加,引起电网电流、电压波形发生畸变,造成电网的谐波污染和电能损失；同时,冲击性负载及无功补偿不足常引起电网电压跌落和闪变,影响企业的正常生产和人民的日常生活,并导致线路损耗增加。目前我国的输配电线损率为6.72%左右,若能达到西方发达国家的4.7%左右,每年可节约电能740亿度以上,谐波污染严重、无功补偿不足、电压波动频繁等电能质量问题是导致我国电能损耗高的重要原因。针对配电网电能质量控制的关键瓶颈问题,本文以国家自然科学基金项目和国家"863"计划项目为依托,详细阐述了高效电能质量控制的内涵,从高效无功与谐波动态控制系统新型拓扑结构和控制装置优化规划方法两个层面,深入研究了企业配电网高效无功与谐波综合动态控制的相关理论和方法。研究内容涵盖了高效无功与谐波动态控制系统的工作机理分析、数学建模、控制算法、优化运行、以及工程应用时的关键技术问题等方面,形成了较为完善的高效无功与谐波动态控制方法的基本研究方法和技术方案,研究重点及取得的成果主要体现在以下几个方面：(1)提出了一种兼顾HAPF和SVC优势、克服其各自不足的配电网高压系统高效无功与谐波混合控制器HVHC,在分析HVHC基本工作原理的基础上建立了其电气模型。深入研究了HVHC系统的工作特性,揭示了HVHC i皆波动态治理子系统和无功连续调节子系统间相互耦合的本质,在此基础上提出了HVHC复合控制方法,实现了谐波动态治理子系统和无功连续调节子系统间的解耦控制。HVHC实现了配电网高压系统的谐波及无功功率的综合动态补偿,并具备补偿不平衡、电压支撑、阻尼振荡等功能,大幅降低了配电网的谐波损耗和无功损耗。(2)着重研究了电网电压发生波动、电压畸变等系统异常情况时,HVHC直流侧电压的稳定性问题；在剖析HVHC直流侧电压抬升机理的基础上,提出了优化HVHC注入支路参数、改进HVHC有源部分主电路结构以及复合控制方法等三种稳定直流侧电压以提高系统可靠性的方法,确保了HVHC直流侧电压的稳定及HVHC系统的可靠运行。(3)提出了兼顾成本和性能优势的配电网低压系统高效混杂无功补偿器HHVC进行低成本大容量无功动态调节,并具备滤波功能。在分析HHVC的基本结构和建立电气模型的基础上,对采用基于检测负载谐波电流控制策略下HHVC的稳定性、运行机理进行了深入研究,揭示了HHVC运行的内在本质；同时在分析HHVC连续子系统和离散子系统交互影响的基础上,提出了HHVC专家协同控制方法,确保了系统的经济、稳定运行。(4)建立了配电网的谐波域摄动模型,在此基础上提出了无功与谐波综合优化规划问题的数学模型,为无功与谐波综合优化规划问题的求解奠定了基础；提出了无功及谐波综合优化规划的启发式频域摄动分析法HPFA。HPFA法首先提出了频域摄动量分析,获得了高效无功及谐波补偿装置的最优配置集,提出了启发式精确搜索算法,实现了对无功及谐波综合优化规划目标函数的快速、精确求解,为谐波及无功综合动态治理装置工程应用时以较低的成本获得较优的治理效果提供了理论指导。(5)以合肥某铜材厂35kV配电网电能质量综合控制工程为背景,利用本文提出的无功与谐波优化规划的启发式频域摄动分析法为该厂设计了高效无功与谐波控制系统的最优安装位置和容量；针对该厂谐波及无功的实际工况,并结合HVHC、HHVC系统的运行特点,为该厂设计了电能质量控制整体技术方案；为提高HVHC、HVC系统的控制性能及确保装置的长期可靠运行,对HVHC、HHVC系统工程应用时的若干关键技术难题进行了研究,并提出了相关解决措施；最后,为该厂研制了HVHC、HHVC装置,装置投运后运行效果良好,企业产品质量显著提高、节能降耗效果明显。本文以配电网电能质量控制、企业电气节能需求为背景,提出了高效无功与谐波混合控制器HVHC和高效混杂无功补偿器HHVC,并对谐波及无功综合优化规划问题进行了研究。HVHC、HHVC克服了单一电力电子在功能上的局限,实现了配电网高低压系统的谐波、无功动态治理,电压支撑及闪变抑制等。论文对HVHC、HHVC的研究方法,可以为其它高效电能质量控制装备的研究提供一定的借鉴意义；工程应用的整体方案设计思路和一些工程经验还可推广到其它电能质量控制电力电子系统的设计和应用中,为推进电力电子混合、混杂系统的实用化进程提供有益的参考和借鉴。更多还原

【Abstract】 Electrical energy plays an important role in the economic development and people’s lives. With widely used of the non-linear load in the grid, the supply current and voltage become distortion which causes harmonic pollution and energy losses. Meanwhile, voltage fluctuation and voltage flicker caused by the impulsive load and reactive power variation have greatly disturbed the industrial production and people’s lives. It also increases the line loss of the grid. The line loss rate of distribution grid is about 6.72% in our country. It can save more than 74 billion kWh per year, if the line loss rate reaches about 4.7% of the Western developed countries.Aiming at the key problem of power quality control technology in distribution grid, and based on the financial support of The National Natural Science Foundation of China (Project No.60774043) and The National High Technology Research and Development of China (863 Program) (Project No.2008AA05Z211), the connotation of the high-effiency power quality control is firstly explained in detail in this paper. Novel theories and methods of high-effieccy reactive power compensation and harmonic elimination in distribution grid have been studied in a deep-going way. Two novel comprehensive power quality controller, named High-efficiency Var and Harmonic hybrid Controller (HVHC) and High-efficiency Hybrid Var Controller (HHVC), were proposed to improve the power quality and decrease power losses. The working mechanism, mathematical model, control method, optimal operation and the critical technical problems in application of comprehensive power quality controller are described in detail in this paper. The emphasis and achievement of the paper mainly manifests in the following aspects:(1) High-efficiency Var and Harmonic hybrid Controller (HVHC) is proposed to realize harmonic currents dynamical suppression and reactive power dynamical compensation at the same time in high voltage distribution grid. The shortcomings of HAPF and SVC are avoided in this system. Based on the analysis of its working principle, the electric model is established. The compensation characteristics of harmonic and reactive power are also given in this paper. Furthermore, suppressing coupling crosstalk hybrid control strategy is proposed to eliminate the infection between SVC and IHAPF. Simulation and experiment results show that, HVHC can realize the harmonic currents dynamical suppression and reactive power dynamical compensation at same time. It can also realize the unbalance compensation, voltage support, damping oscillation, etc which can reduce the harmonic losses and reactive power loss greatly.(2) This paper mainly focuses on the DC voltage stability of HVHC under interference. Based on the analysis of HVHC’s DC voltage problem, optimizing the parameters of HVHC’s injection circuit, improving the main circuit of HVHC’s active part and composite control strategy are proposed to improve system reliability.(3) This paper proposes a High-efficiency Hybrid Var Controller to realize the low-cost, high-capacity continuous adjustment of reactive power. It can also eliminate harmonic currents and flicker, which has significantly improved the power quality and power utilization of low-voltage distribution grid. Based on the topology and electrical model of HHVC, the stability and operation mechanism are described in detail in the control strategy of detecting the load’s harmonic current. HHVC expert cooperative hybrid control method is proposed in this paper to maintain the economic and stable operation of system.(4) Based on the establishment of node admittance matrix in harmonic domain, harmonic power flow calculation method of distribution grid is described in this paper. Heuristic Perturbation Frequency domain Analysis method is proposed to arrange the compensation device and simplify the iteration calculation of power flow. Sensitivity analysis is used to get the reasonable installation location. Combining the advantage of Benders decomposition method in solving mixed integer problems and Lagrange multiplier method in getting the optimal solution of continuous variable, a method is used to obtain the optimal solution in the alternative solutions. At last, harmonic suppression and reactive power optimization planning are described in detail in this paper. Simulation results verify the validity of the proposed method in this paper.(5) Based on the project of harmonic suppression and var compensation in a 35kV distribution grid in copper material factory, several critical technical problems in the application of power electronic hybrid system HVHC and HHVC are described in detail in this paper. The power quality technical scheme of this factory is designed. And the application results verify the validity of the proposed method in this paper.Based on the proposed theory and design method, this paper makes a deep research on several critical technical problems in the application of power electronic hybrid system HVHC and HHVC to meet the industrial need on harmonic suppression and var compensation in large industrial enterprise. The overall design scheme of HVHC and HHVC is described in detail in this paper. The compensation system of HVHC and HHVC has been developed. The application result shows that the compensation system has good performance and the power quality of this enterprise has improved greatly.Accroding to the research of distribution grid power quality control and the electric energy saving of enterprise, power electronic hybrid system HVHC and HHVC are proposed in this paper. Besides, harmonic suppression and reactive power optimization planning are also described in detail. HVHC and HHVC overcome the shortcomings of single power electronics in compensation performance, realizing the dynamic compensation of harmonic and reactive power, voltage support and flicker suppression in the high and low voltage side of distribution grid. The research on HVHC and HHVC is very practical for the other researches of power electronic hybrid system. The overall program design ideas and some engineering experience can be extended to the design and application of other power electronic systems. It also provides a useful practical reference for the development of power electronic hybrid system.更多还原