【作者】 徐先勇；

【导师】 罗安；

【作者基本信息】 湖南大学 ， 电气工程， 2010， 博士

【摘要】 随着我国特高压交流输电工程的发展和特高压交流电气设备国产化能力的提升,无论是在特高压交流输电技术的研究上,还是在特高压交流电气设备的绝缘考核上都离不开特高压交流试验电源。因而展开特高压交流试验电源的研究具有重大意义,可极大推动我国特高压电网的发展和提高其运行的稳定性。目前,我国在特高压交流试验电源理论、关键技术和其工程应用方面的研究较少。本论文以国家电网公司1000kV级交流特高压输变电工程关键技术—调频式谐振特高压试验电源(Ultra High Voltage Frequency Tuned Resonant Test Power Supply, UHV-FTRTPS)项目为依托,以调频式谐振特高压试验电源的理论研究和工程应用为主线,研究内容涵盖了调频式谐振特高压试验电源的基本工作原理、拓扑结构、主要结构部件设计与制作、控制算法和特高压交流输电现场工程应用等方面,形成了一套较为完善的关于调频式谐振特高压试验电源的理论、关键技术、装置研制与应用方案。在对调频式谐振特高压试验电源通用结构和基本谐振方式介绍的基础上,对本论文提出的基于模拟放大器的UHV-FTRTPS基本原理和结构进行了详细阐述,深入研究了该类型特高压试验电源主要部件的电路及工艺特点、工作原理和关键参数的选取。并首次分析了被测试品容值(即特高压电气设备)的大小、整个电源重量与负载容性无功之间的关系、特高压谐振电路品质因数与UHV-FTRTPS输出电压信号频率上限之间的关系,从理论上指出UHV-FTRTPS输出信号频率上、下限分别为30和300 Hz较为合适。同时结合基于模拟放大器的UHV-FTRTPS电路的特点,对其调幅、调频控制方法进行了深入研究。提出的智能调频控制算法可以依据频率误差对频率进行先‘粗调’后‘细调’,精度可达0.1 Hz。提出的模糊最优非线性PI调幅控制策略,在大偏差范围内采用模糊控制,以获得更好的瞬态性能；在小偏差范围内采用最优非线性PI控制,以获得更好的稳态性能及超调抑制性能。整个控制算法具有响应速度快、鲁棒性强的特点。随着电力电子技术的发展,各种功率开关器件不断面世,借鉴现代电力电子技术,本论文提出一种基于不可控整流-H桥逆变的调频式谐振特高压试验电源,介绍了它的基本工作原理和谐振原理。并对其大功率H桥逆变器的缓冲电路和输出滤波器进行了优化设计,从缓冲电路抑制IGBT关断过电压能力、自身损耗和器件投资三个方面出发,建立了缓冲电路优化设计的目标函数；从大功率H桥逆变器输出滤波器初期投资、输出滤波器输出电压和电流信号畸变率、输出滤波器基波压降几个方面出发,建立了输出滤波器优化设计的目标函数；采用模糊优化方法来求解这两个多目标优化函数。对于该类型UHV-FTRTPS的调幅控制提出了电压调节自调整PI控制方法、调频控制提出了一种新的PI锁相自动调频控制方法,不仅具有计算量小、易于工程应用的特点,而且还省去了频率设定值。为了精确保证特高压试验电源整流输入侧电压与电流同相位,最大程度消除UHV-FTRTPS对电网的影响,本论文提出基于可控PWM整流-H桥逆变的调频式谐振特高压试验电源结构。针对可控PWM整流电路,提出了电源电压辨识的PWM整流器控制策略。针对逆变器及特高压谐振电路,提出以特高压谐振电容电压有效值为外环,以逆变器输出滤波器电容瞬时电流为内环的调幅、调频控制策略,因内环被控量为正弦量,故采用一种多模递推PID控制算法,能很好地消除周期变化信号所产生的稳态误差。为了得到特高压试验电源输出信号最佳波形,在167-300Hz高频率段采用同步SPWM调制,使逆变器输出滤波器在具有较小体积的情况下,获得最佳载波比N；在30-167Hz低频率段,采用特定次谐波消除方法在线计算各开关角度,消弱低次谐波,利于输出滤波器滤除高次谐波；同时,还引入虚拟电阻到LCL输出滤波器中,增强其滤波性能。本论文所研究的几种不同结构UHV-FTRTPS都拥有一个共同部分—特高压无局放产生电路,包括：中间励磁升压变压器、高压谐振电抗器、高压补偿电抗器、高压测量谐振电容器和均压环。从工艺制作和现场需求出发,给出了特高压无局放产生电路各个部件的详细参数和制作过程,并保证了各个部件具有很小的局部放电量。同时对特高压无局放产生电路的各个部件进行了型式试验,试验结果表明各个部件设计合理、符合标准要求。针对特变电工衡阳变压器厂生产的特高压变压器的局部放电试验,本论文提出了相应的试验方案；还针对特高压交流试验示范工程荆门变电站的1100kV等级GIS装置的交流耐压试验,本论文也提出了相应的试验方案；使用本文研制的基于模拟放大器的大功率UHV-FTRTPS分别对特高压变压器和GIS进行了工程现场试验,工程试验结果表明该特高压试验电源装置能够很好地完成特高压电气设备试验需求；并总结了基于模拟放大器的UHV-FTRTPS在工程实际应用中的关键问题,给出了解决方法。更多还原

【Abstract】 With the development of China’s UHV AC Transmission Project and the improvement of UHV AC electrical equipments’localization, whether in the research of UHV AC Transmission technology, or in the insulation testing of UHV AC electrical equipments, the UHV AC Test Power Supplies are indispensable. Thus, research on UHV AC Test Power Supply has great significance, which would greatly promote the development of UHV AC power system of China and improve its operation stability. At present, the research on the theory of UHV AC Test Power Supply, key technology and its engineering application are few in our country.Based on the key technologies of UHV AC power transmission project of State Grid Corporation-UHV Frequency Tuned Resonant Test Power Supply (UHV-FTRTPS), this paper proposes a most completely theory, key technologies, equipment research and applications relying on UHV-FTRTPS. It takes theoretical study and engineering application of UHV-FTRTPS as the main line. It also studies the basic working principle, topology, design and production of the main structural components, control algorithms of UHV-FTRTPS and the field engineering application of UHV AC Transmission, etc.Based on the introduction of universal structures and basic resonant methods of UHV-FTRTPS, this paper gives the detail description of UHV-FTRTPS’s basic principles and structure on the basis of analog amplifiers. This paper also makes further research on the subcircuits, technological features, working principle and key parameters selection of this type. This paper also gives the first description of the relationship between the size of UHV electrical equipment, the weight of the entire power supply and the capacitive reactive power of the load. In addition, the relationship between the quality factor of UHV’s resonant circuit and the frequency’s upper limits of UHV-FTRTPS’s output voltage has also been proposed. It can be found that UHV-FTRTPS has a good performance when the frequency’s upper and lower limits are 30Hz and 300Hz respectively. Combined with the characteristics of UHV-FTRTPS’s circuits based on the analog amplifiers, deeply study on the amplitude and frequency control methods of voltage have been carried out. According to the proposed intelligent control algorithm, the output signal frequency can be had coarse tuning first, then had fine-tuning. The accuracy of frequency control is up to 0.1 Hz. Moreover, the fuzzy optimal nonlinear PI of voltage amplitude modulation was proposed in this paper. Fuzzy control was used in large deviation range to obtain better transient performance. While, optimal nonlinear PI control was used in small deviation range, to obtain better steady-state performance and overshoot suppression performance. The whole control algorithm has the fast response and robustness.With the development of power electronics technology, a variety of power switching devices are continuously available. This paper proposes a new UHV-FTRTPS based on Non-controllable rectifier and H-bridge inverter by applying present power electronic technology. This paper gives the basic principle and resonance Principle of this UHV-FTRTPS. Buffer circuit and output filter of high-power H-bridge inverter are optimum designed in this paper. On one hand, optimization objectives of buffer circuit has been set up, according to the ability that the buffer circuit suppresses IGBT’s turn-off over-voltage, its own power loss and the investment of the devices, on the other hand, objective functions about the optimal design of output filter have been established based on the initial investment of high-power H-bridge inverter’s output filter, output filter’s output voltage, THD of current and the fundamental voltage drop of output filter. Fuzzy optimization method is used to solve the two multi-objective functions. Voltage self-tuning PI control method has been designed for the voltage amplitude control of UHV-FTRTPS. A novel phase-locked PI automatic frequency method was proposed for the frequency control of UHV-FTRTPS. The proposed phase-locked PI control method not only has smaller amount of calculation and is easy for engineering application, but also does not need frequency setting value.In order to ensure that the voltage and the current at input side of UHV’s rectifier have same phase, eliminate UHV-FTRTPS’s impact on the grid as much as possible, this paper proposes the topology of UHV-FTRTPS based on controllable PWM rectifier and H-bridge inverter. The source voltage estimation is presented in the PWM rectifier controller. This paper also presents the double closed loop control strategy, which takes resonant capacitor voltage as outer loop and output filter capacitor current as inner loop. The controlled variable of inner loop is a sine quantity, so the multi-mode recursive PID is used to eliminate steady-state error which generated by periodic changed signal. In order to get the best output signal waveforms of UHV-FTRTPS, the synchronized SPWM is used in 167-300Hz high frequency bands. Meanwhile in order to get best carrier ratio N and minimum apparent power filter of output filter, the value of carrier ratio N and the structure of output filter are combined. The SHEPWM is used to real-timely calculate the switching point in 30-167Hz low frequency bands. The low-order harmonics is weakened and transferred to the high-order harmonics, so the harmonics is easy to be filtered. At the same time, to improve filtering performance of LCL output filter, the virtual resistance has been introduced to its structure. The capacitor of output filter in series with a virtual resistance does not change the structure of output filter and add any hardware. The software control method is used to enhance the damping of output filter, so the high-order harmonics can be filtered easily.The different Topologies of UHV-FTRTPS studied in this paper have a common part-UHV generating circuit without partial discharge(PD), which is included intermediate excitation step-up transformer, high-voltage resonant reactors, high-voltage compensation reactors, high-voltage measured resonant capacitors and grading ring. Considering the fabrication and on-site needs, this paper gives the detailed parameters and production processes of every component and maintains every component have a small amount PD. At the same time, every component’s type has been testified. The result shows that the design of every component is reasonable and meets the standards. According to the partial discharge test of TBEA Hengyang Transformer Factory’s UHV transformer, this paper proposes a corresponding experiment program. Aiming at the 1100kV gas insulated switchgear(GIS) device’s AC voltage withstand test of UHV AC experiment demonstration project Jingmen substation, this paper also proposes a corresponding experiment program. The proposed high-power UHV-FTRTPS based on analog amplifiers was used in the field experiment of UHV transformer and UHV GIS. The engineering application results show that this high-power UHV test power supply device can meet the requirements of UHV electrical equipment. In addition, this paper draws a conclusion about the key issues of UHV-FTRTPS’s engineering applications and gives the solution of them.更多还原