【作者】 李满；

【导师】 周雪松；

【作者基本信息】 天津理工大学 ， 电力系统及其自动化， 2012， 硕士

【摘要】 混合级联多电平逆变技术是多电平逆变技术的一项创新性技术，它具有改善输出波形、降低器件的耐压、省去变压器、减少成本等优点，使其成为高压大容量STATCOM（Static Synchronous Compensator，STATCOM）的研究热点。应用混沌理论和随机频率脉宽调制（Random Frequency Pulse Width Modulation，RFPWM）的调制策略对混合级联多电平逆变器的STATCOM进行调制，具有重要的理论研究和工程实用价值。本文对混沌理论的随机性能、拓扑的传递性能和周期点集在相空间中稠密性的特性进行研究，为了改善单一混沌序列的性能，搭建了基于Chebyshev混沌序列和无限折叠混沌序列的新型混沌序列。仿真结果验证新的混沌序列拥有比单一混沌序列更好的随机性能和迭代速度。本文分析了混沌序列的特性和RFPWM的原理，提出了一种基于混沌序列RFPWM的调制策略。为了提高混合级联多电平逆变器的运行性能，减少电磁噪音和降低谐波，把基于混合混沌序列的RFPWM应用在混合级联多电平逆变器中。仿真结果验证新型混沌序列RFPWM的混合级联多电平逆变器可以有效的降低整体谐波的幅值，降低噪音，提高开关器件的利用率，提高逆变器件的寿命。STATCOM装置稳定运行的关键在于能否实时、准确地检测出系统的无功和有功电流，本文对基于p q和d q两种方法进行分析，选择基于d q的瞬时无功功率理论的检测技术，对STATCOM的无功电流进行动态实时检测。理论分析表明d q的检测方法可以快速、准确的检测出无功电流，同时不受谐波的影响。同时采用状态反馈的控制策略实现基于混合混沌序列RFPWM的STATCOM控制，并应用于电网中，开环和闭环仿真表明在大幅度减少谐波幅值，提高STATCOM性能的同时有效地提高了STATCOM的响应速度。更多还原

【Abstract】 As an innovation technology in multilevel inverter，since the hybrid cascaded multilevelinverter can improve the quality of output waveform, reduce the voltage resistance ofswitching devices, save the transformers and greatly reduce the cost, it has been a hot topic inthe large-capacity research on STATCOM.In this paper the performance of chaos theory on the randomness，the topology ofcontagion and the density of point set of cycle in the phase space has been studied. In order toimprove the character of the single chaos sequence, a new chaos sequence based onChebyshev chaotic sequences and chaotic sequence with infinite collapse is built. Thesimulation results show that the new chaotic sequence has better random performance anditeration speed than single chaotic sequence. Through the character of chaos sequence and theprinciple of the RFPWM are analyzed, and a new modulation strategy based on RFPWM ofchaos sequence is presented. For improving operation performance of the hybrid cascadedmultilevel inverter and reducing electromagnetic noise and the harmonic, modulation strategyof RFPWM of chaos sequence is applied to the hybrid cascaded multilevel inverter. Thesimulation analysis is validated that the hybrid cascaded multilevel inverter based on the newchaos sequence can effectively reduce the overall harmonic amplitude, and reduce the noiseof inverter, as well as improve the switch device utilization rate and life of the inverter device.Being able to accurately detect the reactive and active current of system characteristics inreal time is the key of STATCOM steady operation. After the methods of p qand d qarecomparatively analyzed, the d qinstantaneous reactive power theory of testing technology ischose. Theoretical analysis indicates that reactive current can be fastly and accurately detectedby this method avoiding the influence of harmonic. The control method of states feedbackdecoupling based on RFPWM of hybrid chaotic sequence is presented, and applied to powergrid. The simulation results based on open loop and closed loop show that the above methodcan greatly reduce the harmonic amplitude, improve the performance of STATCOM, andeffectively ameliorate the response speed of STATCOM.更多还原