【作者】 唐杰；

【导师】 罗安；

【作者基本信息】 湖南大学 ， 电气工程， 2007， 博士

【摘要】 配电网静止同步补偿器(D-STATCOM)是一种重要的“用户电力(Custom Power)”装置,在配电网中能有效的解决电压波动与闪变、三相电压不平衡、电网谐波污染等电能质量问题。论文对D-STATCOM用来改善配电网电能质量时的电压控制策略、电网电压不平衡条件下D-STATCOM的运行性能及不平衡控制策略、补偿电流检测与控制技术、功率开关器件的驱动和缓冲电路参数优化设计等理论和关键技术进行了系统深入的研究,主要包括以下几方面的内容。补偿无功和电压是D-STATCOM装置的基本功能。D-STATCOM通过与公共连接点(PCC)进行无功功率交换,可以使公共连接点电压维持在参考电压值。为了使D-STATCOM装置具有良好的电压补偿性能,电压控制器的性能显得至关重要。论文的第2章针对传统的D-STATCOM电压控制策略存在的不足,以瞬时无功功率理论为基础,从功率交换的角度详细地分析了D-STATCOM系统中的功率交换关系,推导出了D-STATCOM逆变器的输出电压与指令电流之间的转换关系,进而提出了基于瞬时功率平衡的直接电压控制策略。由于该控制策略在实现过程中要利用到D-STATCOM系统中连接电抗器的等效电气参数,所以控制器的控制性能会受到等效电气参数的影响。同时考虑到D-STATCOM数学模型的不精确性,论文将模糊自适应PI控制引入到D-STATCOM控制系统中,使得控制器不仅结构简单、容易实现,而且还具有鲁棒自适应性能。对控制策略进行了数字仿真研究,仿真结果证明了控制策略的正确性和有效性。不平衡控制是D-STATCOM实现工程应用时所面临的技术难题之一。电网电压不平衡现象在配电网中普遍存在,电网电压的不平衡会给D-STATCOM装置造成不利影响。论文的第3章首先应用开关函数法和序网络分析法从D-STATCOM逆变器的输出性能和装置的过流两方面详细地分析了电网电压不平衡对D-STATCDOM装置的影响。然后提出了综合利用改进的开关函数调制法和负序电压前馈控制的不平衡控制策略,克服了单独使用改进的开关函数调制法和负序电压前馈控制策略存在的缺陷,解决了D-STATCOM输出电流中的谐波问题和装置的过流问题。为了利用D-STATCOM改善供电电压的不平衡度,论文的第3章提出了正、负序双控制环相叠加的不平衡控制策略,正、负序控制环均实现了无电流传感器控制,使D-STATCOM既能很好的补偿电压又能改善不平衡度。D-STATCOM装置除了补偿无功功率和电压外,也可以用来实现对负荷的综合补偿。拓宽D-STATCOM的应用范围,提高D-STATCOM装置的性价比也是D-STATCOM未来发展的一个方向。利用D-STATCOM来实现对负荷的综合补偿时,补偿电流的检测和控制技术是其中的两大关键技术。论文的第4章提出了一种改进的基于电源电压矢量的同步参考坐标变换检测法,该方法无需锁相环电路,且在电网电压不平衡条件下仍能准确的检测出负载电流中的无功、谐波和负序分量,满足D-STATCOM负荷综合补偿的要求。D-STATCOM用于负荷综合补偿时其补偿指令电流为不规则的非正弦信号,常规的电流跟踪控制技术很难使D-STATCOM的输出电流能很好的跟踪补偿指令电流的变化。针对补偿指令电流信号的特点,论文的第4章将基于空间矢量的滞环电流控制技术引入到D-STATCOM用于负荷综合补偿时的电流跟踪控制之中,取得了不错的控制效果。D-STATCOM装置要实现安全、稳定运行,在很大程度上取决于主电路功率开关器件的运行情况。为了使功率开关器件稳定、可靠的工作,必须为其设计性能优良的驱动电路和缓冲电路。论文的第5章从工程开发周期和驱动电路的性能出发,提出了一种基于SCALE器件的IGBT智能集成驱动保护方案。该方案采用了智能集成驱动器2SD315A作为D-STATCOM功率开关器件IGBT的驱动电路,该驱动电路集驱动、隔离和保护为一体,且开发周期短,适合于D-STATCOM实际装置的开发。论文给出了该方案实现过程中的一些技术细节,可以为同类型的电力电子设备的开发提供参考。论文的第5章还设计了一种D-STATCOM主回路新型结构,使得主回路电感更小,从而更好的抑制瞬态电压。此外,针对目前根据工程经验来设计缓冲电路所存在的问题,提出了基于模糊多目标优化的缓冲电路参数设计方法,实践证明这种方法是切实可行的。论文的第6章在前面几章相关理论和技术的指导下成功研制出了±50kvar的D-STATCOM实验装置,并在实验样机上进行了大量的实验。实验结果与仿真结果相吻合,验证了上述理论和技术是正确而有效的。论文最后对全文工作进行了总结,对D-STATCOM今后的研究方向和应用前景进行了展望。更多还原

【Abstract】 Distribution Static Synchronous Compensator (D-STATCOM) is an important "Custom Power" device, which can be an effective solution to power quality problems such as voltage fluctuation and flicker, three-phase voltage imbalance and harmonics pollution. Based on laboratory±50kvar D-STATCOM devices for the development background, D-STATCOM voltage control strategy, unbalanced control strategy, compensation current detection and control technology, power switching device drivers and snubber circuit design parameter optimization theory and key technology for the system in-depth were studied.Reactive compensation and voltage control are the basic functions of D-STATCOM. D-STATCOM can make the voltage of PCC maintain the voltage reference voltage value through reactive power exchange with the power system. For D-STATCOM devices with good voltage compensation performance, voltage controller design is crucial. In the second chapter aims at the shortcomings of the traditional voltage control strategy of D-STATCOM, on the basis of instantaneous reactive power theory, power exchange from the perspective of a detailed analysis of the D-STATCOM system of power exchange, derived from the D-STATCOM output voltage instructions and directives for conversion between the current relationship thus the balance of power based on instantaneous voltage direct control strategy. As the realization of the control strategy the connect reactor equivalent electrical parameters are used. Therefore, the performance of the controller will be influenced by equivalent electrical parameters. At the same time taking into account the D-STATCOM mathematical model of accuracy, the adaptive fuzzy PI control is used in D-STATCOM control system, which makes not only simple, easy to implement, but also robust adaptive performance, simulation results prove this point.Unbalanced control is a technical difficulties when D-STATCOM realization of the project application. Grid voltage imbalance prevailing in power system, power system voltage imbalance will give D-STATCOM adversely affected. In the third chapter the output performance of inverter for D-STATCOM and the overcurrent phenomena of D-STATCOM are analyzed detailed under power system voltage is imbalance. A comprehensive utilization of improved switching function modulation and negative sequence voltage feedforward control the imbalance control strategy overcome alone improve the switching function modulation and negative sequence voltage feedforward control strategy to control the imbalance, the defects solve the D-STATCOM output current harmonics of the device and overcurrent problems. In order to take advantage of D-STATCOM improve the supply voltage imbalance positive and negative sequence control loop superimposed imbalance control strategy is proposed in the third chapter is. From simulation and the experimental results, this imbalance control strategy is feasible.D-STATCOM devices in addition to compensation of reactive power and voltage, but also can be used for load comprehensive compensation. Broaden D-STATCOM scope of application enhance D-STATCOM device’s cost-effectiveness is D-STATCOM future development of a direction. When using D-STATCOM to achieve a load comprehensive compensation, compensation current detection and control technology is one of the two key technologies. In the fourth chapter a modified vector based on the supply voltage synchronous reference coordinate transformation method is proposed. This method is no need PLL circuit and the voltage imbalance conditions can be accurately detected by the load current of reactive, harmonic and negative sequence to meet D-STATCOM load compensation requirements. Consideration of the irregular non-sinusoidal signal of D-STATCOM’s direct current, the conventional current tracking control technology is very difficult to achieve without static error tracking. Because of this, in the fourth chapter based on the vector space hysteresis current control technology is introduced to the D-STATCOM which achieves comprehensive load compensation and achieves good control effect.D-STATCOM devices to achieve security, stability operations depends to a large extent on the main circuit power switching device operation. In order to ensure that the power switching devices stable can reliably work, we must design its excellent performance driving circuit and the snubber circuit. Chapter 5 of the papers from the point of view of project development cycle and drive circuit performance, integrated use of intelligent integrated driving module SD315A as D-STATCOM power switching device IGBT drive circuit, the driving circuit has the function of driving, isolation and protection of integration and development cycle is short so suitable for D-STATCOM practical device development. In the fifth chapter also designed a D-STATCOM new main circuit structure, the main circuit inductance makes smaller and better transient voltage suppression. In addition, a fuzzy-based multi-objective optimization of the design parameters of the snubber circuit, practice has proved that the method is feasible. In the sixth chapter of the paper under the guidance of the above theories and technologies a±50kvar D-STATCOM prototype is development. A large number of experiments are implemented on the experimental prototype. The experimental results match with the simulation results. The correction and effective of the theories and technologies are verified by the experimental results.更多还原