【作者】 何娜；

【导师】 徐殿国；

【作者基本信息】 哈尔滨工业大学 ， 电力电子与电力传动， 2008， 博士

【摘要】 随着电力电子装置的广泛应用,在给电能的变换应用带来方便的同时也给电力系统带来了严重的谐波和无功污染。为此,研究有源电力滤波器以补偿电力电子装置所引起的谐波和无功污染已成为电力电子应用技术中的一个重大研究课题。由于有源滤波器的初期投资比较高,限制了其进一步应用与发展。将有源滤波器与无源滤波器相结合构成混合有源滤波器,可有效地降低有源滤波器的容量,更利于工程应用。本文首先研究了谐波及无功的检测问题,然后以补偿谐波和无功电流为目的,从控制理论和系统参数优化设计两个方面对并联有源滤波器和混合有源滤波器进行了深入的研究,研究内容包括以下几个方面:新型谐波及无功检测算法的研究。传统自适应谐波检测算法中步长的选择需要在收敛速度与稳态精度之间进行折衷考虑,降低了算法的实用性。为了克服此局限性,本文提出了一种改进的变步长自适应谐波电流检测方法,它利用滑动积分器提取出真正的跟踪误差,并采用带有自调整因子的模糊调整器来动态调整算法的步长,从而提高了谐波检测的动态响应速度与稳态精度。为了简化系统设计并易于硬件DSP实现,本文采用了非均匀量化的模糊化和清晰化规则,而且由于自调整因子的存在,此模糊调整器可以根据检测系统的实际情况对调整规则进行自动、实时地调整,增强了整个算法的鲁棒性。最后讨论了该算法在三相系统及各次谐波或无功均需检测情况下的应用,拓宽了算法的应用范围。并联有源滤波器控制策略的研究。为了实现并联有源滤波器的电流无差跟踪控制,本文将广义积分控制器引入APF电流跟踪控制环节中,并对有源滤波器广义积分控制策略及其无差特性进行了详细的分析研究。为了进一步提高控制系统的鲁棒性和抗干扰性,本文设计了一个辅助模糊调整器来根据系统的实际情况,实时地调整广义积分控制器的参数,以同时取得较好的稳态精度与动态响应速度。有源滤波器控制的另一个方面是直流侧电容电压的控制。为了更好地设计直流侧电压控制器,使直流电容电压稳定在参考值上,并实现有源滤波器平滑地投入启动,本文设计了直流侧电容电压的模糊和PI复合控制器。此控制器可以根据系统的实际情况对控制规则进行自动、实时地调整,具有PI控制稳态精度高、模糊控制鲁棒性强及自适应的优点。单调谐混合有源滤波器优化设计方法。本文推导分析了现有常用的并联混合有源滤波器中有源部分的容量与直流侧电容电压特性,并对各种混合拓扑结构的容量进行了详细的分析比较。在此基础上,针对单调谐混合有源滤波器,区别于已有的设计思路,基于有源滤波部分容量最小的原则,提出了单调谐混合有源滤波器中无源滤波支路参数的一种新的优化设计方法。并针对所设计的拓扑结构,提出了一种新型复合控制策略,在不影响系统稳定性的基础上,提高了系统的滤波性能,保证了混合有源滤波器小容量下良好的运行性能。适用于中、高压情况下的大容量混合有源滤波器多目标优化设计的研究。本文依托一个课题项目为背景,设计了一套并联混合有源滤波器,并将混合有源滤波器参数设计问题转化为一个多目标加约束的优化问题,详细地建立了其多目标优化模型,综合考虑了系统成本、滤波效果、无功补偿等因素,并将系统失谐性测试作为约束条件来处理。在此基础上,首次将粒子群优化算法引入混合有源滤波器多目标优化设计问题的求解当中。通过对混合滤波系统进行优化设计的研究,可以更加合理地设计和优化它们的各个参数,从而更好地发挥它们的作用,对保证系统的正常工作,提高整个混合有源滤波器的经济性、实用性起到了至关重要的作用。更多还原

【Abstract】 The development of power electronics brings convenience to energy conversion and utilization on one hand and also causes harmonics and reactive power problems on the other hand. So the study on active power filter for compensating harmonics and reactive power becomes an important issue in the fields of power electronics. The initial investment of active power filter is very high, which limits the development and application of active power filter. The hybrid active power filter, which combines active power filter and passive power filter, can availably reduce the capacity of active power filter and is more appropriate for engineering applications. First the detection method of harmonics and reactive power is studied in this paper. Then the shunt active power filters and hybrid active power filters are detailed in two aspects of control strategies and system parameters design in order to compensate harmonic and reactive power. The investigated contents are shown as follows.The study on a novel detection method of harmonic and reactive current is carried out. The selection of the step-size in conventional adaptive harmonic detection method will make a compromise between convergence speed and steady precision, which restrict its practicability. In order to conquer this disadvantage, an improved variable step-size method is proposed in this paper. This proposed method adopts a sliding integrator to obtain the real tracing error and then uses a fuzzy adjustor with a self-adjustable factor to modify the step- size, so it can obtain both fast convergence speed and high steady precision. For simplifying system design and realization with DSP, the method of non-uniform quantization is adopted during the process of fuzzification and defuzzification in the proposed fuzzy adjustor. The self-adjustable factor can regulate in the whole region and modify the adjusting strategies according to the system state instantaneously, which assures good robustness and excellent dynamic responses. Finally the applications of the proposed adaptive harmonic detection method in three-phase system and some other situations are investigated, which generalizes the application range of the proposed algorithm. The control strategies of active power filter are investigated. In order to realize zero-error-control, the generalized integrator is introduced into the current controller of active power filter. The control strategies of active power filter and its zero-error characteristics are detailed. Additionally, a fuzzy adjustor is designed to improve the robustness of current controller through modifying parameters of the generalized generator, thus both excellent steady performance and fast dynamic response can be obtained.Another control issue for active power filter is the control of DC-link voltage. In order to maintain the DC-link voltage value and realize soft startup, a combined controller, containing conventional PI and fuzzy controllers, is designed to control DC-link voltage. This combined controller absorbs the merits of PI and fuzzy controllers, so it has high accuracy in steady state and strong robustness and excellent self-adaptability in transient state.The optimal design of single-tuned hybrid active power filter is developed. In this paper the capacities and DC-link voltage characteristics of active power filters in hybrid active power filters are derived, and the capacities of several hybrid active power filters are compared in detail. Based on that, a novel optimal design method is proposed for the single-tuned hybrid active power filters in order to minimize the capacity of its active power filters. Additionally, a combined controller is designed for the novel hybrid topology, which contributes to both filtering characteristics and system stability.The multi-objective optimal design of hybrid active power filter set at medium and high voltage bus is developed. A hybrid active power filter is designed for a project. And the design of parameters for this hybrid active power filter is turned into a multi-objective optimal problem with restrictions. The factors of system investment, filtering performance, reactive power compensation, and detuning effects are all considered in this optimal design. And the particle swarm optimization algorithm is first introduced into the optimal design of hybrid active power filter. Through the optimal design method proposed in this paper, the parameters can be designed better so the hybrid active power filter can gain more excellent performance.更多还原