【作者】 刘海春；

【导师】 谢少军；

【作者基本信息】 南京航空航天大学 ， 电力电子与电力传动， 2012， 博士

【摘要】 机场或舰船在对飞机进行地面维护时需要提供400Hz、115V的三相交流电源，即航空地面电源，而目前的直线加电方式的供电电压难以满足相关技术要求。动态电压恢复器（Dynamic voltagerestorer, DVR）在应对电压异常波动、改善电能质量等方面具有突出的优点。本文研究DVR应用于中频电力系统的关键技术，探索提高机场直线加电系统电能质量的新途径。较之于工频电网，中频电力系统具有电压频率较高、电源内阻抗较大且电压受负载影响较大等特点，因此中频DVR的研究具有一定的特殊性。本文在对现有的飞机供电保障方案进行分析的基础上，提出采用DVR以保障飞机地面电源供电质量。本文的研究工作主要包括以下几个方面：1.对机场地面电源的供配电方式进行了分析研究，指出直线加电以其供电稳定、经济、环保等优点必将成为未来机场地面电源的主要供电方式。阐述了在直线加电系统中采用DVR以稳定负载电压的技术可行性及优点。2.对中频DVR的整体技术方案进行全面的研究论证，给出了系统总体结构图。通过对三相四线功率电路拓扑的比较，选择单相全桥电路作为中频DVR的功率电路。为简化系统控制，提出了一种单向馈能的电路方案，从而使DVR始终处于有功补偿的状态，避免了能量倒灌引起的电容电压泵升问题。采用十八脉冲不控整流电路作为DVR的能量提取电路，可实现DVR的不间断补偿，控制简单，同时更低限度地减少对电网电流的谐波污染。分析了整流电路在不同连接点处DVR所对应的电压补偿能力，给出了直流侧电容容量的计算依据。对LC滤波器、降压变压器、串联变压器及功率电路的设计及参数选取进行了研究。3．对DVR电压检测技术进行了深入的研究。为获得准确的电压补偿信号，优化DVR补偿性能，必须对电网电压中的基波分量及其特征值进行相应的检测。首先对现有的电压检测方法进行了分析，在此基础上提出了一种基于周期相位的电压跌落检测方法，该方法实现简单，可以准确实时地对电压幅值跌落及相位跳变进行检测，并判断出电压跌落的起止时间，从而较好地满足中频DVR动态响应快的要求。为提取出电压中的基波分量，提出了一种基于二阶串联谐振滤波器的基波电压检测方法，该方法运算量小，可快速地检测出畸变电压中的基波分量。4．对中频DVR系统的控制方法进行了分析研究。建立了中频DVR的电路模型，以及负载电压有效值闭环控制的控制模型，并对现有的电压控制方法进行了分析比较。通过理论分析和仿真，得出在中频DVR中应用电压有效值控制方法的可行性。对DVR电压补偿策略进行了分析研究，建立了最小能量补偿策略的数学模型。考虑到中频电源电压频率较高且波动较大，容易导致锁相误差，提出了一种基于比例积分（PI）控制的过零锁相方法。对DVR的电压补偿过程进行了分析研究，将该过程分为静态补偿和动态补偿两个阶段，指出电压检测延时和开关周期是影响DVR电压补偿特性的两个关键因素，提出了一种基于相位补偿的电压补偿方案，可实现无延迟的电压补偿。5．在理论分析和仿真研究的基础上，研制了中频DVR样机，针对电网电压的波动及不同负载工况进行了实验测试，取得了一系列的实验结果，并在实际工程项目中进行了应用，进一步验证了DVR应用于中频电力系统的可行性及正确性，丰富了DVR的技术理论，拓展了DVR的实践应用领域。更多还原

【Abstract】 It’s necessary to supply airplane with three-phase400Hz,115V AC voltages which constituteground power unit (GPU) when maintainance is taken on ground or board. However, the presentpower supply of beeline can’t comply with the relevant requirements. Considering the extremelyadvantages of coping with voltage fluction and improving power quality, a study of dynamic voltagerestorer (DVR) applied in400Hz utility is presented in this thesis, which includes its key technologiesand implementation of improving power quality of power supply of beeline.400Hz utility is characterized with higher power frequency, larger inner impedance and easilyaffected by load when compared with50Hz utlity, thus the research on400Hz DVR is distinctive.Based on the analysis of present approaches of power supply of GPU, a new scheme adopting DVR isintroduced.The research of this thesis includes:1. The distribution schemes of GPU of airport are introduced, among which the power supply ofbeeline is taken as the main power supply due to its advantages such as stability, economy,environmental conservation, etc.. The feasibility and virtues of adoption of DVR to steabilize the loadvoltage are also analyzed.2. Based on detailed demonstration of whole technical scheme of mid-frequency DVR, theschematic diagram is given. Singe phase full-bridge circuit is adopted as the inverter power stage ofDVR after the comparison of circuit topology of three-phase four-wire system. To simplify systemcontrol, an unidirectional power-supply scheme is put forward to ensure that DVR only supply activepower to avoid voltage rise of DC capacitor caused by returning of active power. To realize thecontinous compensation and simply the system control, as well as to decline the harmics as possible,the18-pulse uncontrolled rectifier is adapted as the power supply circuit. The voltage compensationcapacity of several connection schemes for the rectifier is analyzed and the design rule of DCcapacitor is given. Meanwhile, the design of LC filter, step-down transformer, series transformer andpower circuit are analyzed in detail.3. A general research on voltage detection is carried out. To obtain the accurate compensationvoltage and promote the DVR’s performance, the detection of fundamental component andparameters of load voltage is necessary. Based on the analysis of traditional detection approaches, anew voltage detection method with easy implementation based on period phase is introduced, fromwhich the amplitude and phase of voltage, as well as the start and end of voltage sag can be judged correctly and quickly, and thus can meet the dynamic requirements of DVR. To extract thefundamental component from voltage, a voltage detection method based on2nd-order serial resonantfilter is presented, which can detect the fundamental voltage quickly with less calculations.4. Research on system control of DVR is introduced. Firstly, the circuit model of DVR along withthe control model of RMS feedback of load are built up, morever, the comparison of several voltagecontrol strategies is carried out. Through therotical analysis and simulation, the feasibility of RMScontrol stategy applied in mid-frequency is validated. After the analysis of voltage compensationstrategies, the mathematical model of minimum energy compensation is given. Considering the higherfrequency and a big variation of frequency of400Hz utility which easily leads to phase-locking error,a new phase locking method with zero crossing based on PI adjustment is proposed. The analysis ofvoltage compensation procedure indicates the composition of steady and dynamic stages, as well asdetection delay and switching period delay acts as the two main factors to affect the compensationperformance of DVR. To eliminate the effect of switching period delay, a new voltage compensationscheme based on phase compensation is put forward.5. Based on the therotical analysis and simulation, a DVR protype is built up and experimental testsare carried out when ultility voltage or load varies, which leads to the application of DVR in practicalengineering project. The experimental results validate the feasibility and correctness of research ofDVR in this thesis and enrich the theory of DVR as well as its practical application.更多还原