【作者】 陈建华；

【导师】 彭建春；

【作者基本信息】 湖南大学 ， 电气工程， 2008， 硕士

【摘要】 光伏水泵系统是太阳能光伏应用领域的一个重要分支,它巨大的社会效益和经济效益越来越多地受到社会的关注。目前,光伏水泵系统中用到的变换器功能单一,市场占有率低,成本较高,这影响了光伏水泵系统的发展。本文针对光伏水泵系统的应用特点,结合电压空间矢量PWM技术(以下简称SVPWM)和感应电机转子磁场定向矢量控制系统原理,对一种调速性能好、具有光伏水泵控制功能的新型变频调速系统进行了研究。SVPWM技术将逆变器和感应电机视为一体。采用SVPWM技术的变频器具有输出转矩脉动量低、直流电压利用率高、开关损耗小、高速调速性能好等优点,适用于高性能电机调速系统。首先,本文从研究SVPWM优化调制方法出发,总结出了三种开关损耗小、适用于高频化逆变器的优化开关模式。其次,本文对SVPWM电压源逆变器应用于感应电机矢量控制系统进行探讨,实现了一种算法简单、应用方便的SVPWM电压源供电型感应电机转子磁场定向矢量控制方案。然后,根据光伏水泵系统的应用特点,详细分析了CVT(Constant Voltage Tracking)和TMPPT(True Maximum Power Point Tracking)两种光伏阵列最大功率点跟踪方法的原理和优缺点,并深入探讨了这两种方法在感应电机转子磁场定向矢量控制系统中的具体实现方法。最后,本文综合SVPWM电压源型感应电机转子磁场定向矢量控制系统和光伏水泵系统的应用特点,设计了一种具有光伏水泵控制功能的新型变频调速系统的控制方案,并对系统进行了空载和负载仿真实验。仿真实验表明:采用本文所提的控制方案,CVT最大功率工作点电压调节快,稳定无震荡,具有较好的动态响应性能和带负载能力。更多还原

【Abstract】 The photovoltaic pump system has become an important part of solar energy application. Futhermore, with its tremendous social and economic advantages, the photovoltaic pump system has been getting more and more attention. Nowdays, converters used in the photovoltaic pump system give priority to special and lower power ones with single function, lower market share and high cost, which may affect the development of the photovoltaic pump system. In this paper, a new function inverter is developed, and it combines the characteristics of the photovoltaic pump system with the technologys of the inverters based on space-vector PWM(SVPWM) and vector-controlled induction motor.SVPWM technique has many good qualities, such as less pulse ating torque, higher use ratio of DC bus voltage, less switching loss, better high-speed regulation performance, so it is applicable for the high-performance motor control system. Starting from optimizing the modulation performance, three kinds of optimal switching pattern of space-vector modulation were established. The vector control strategy of the space-vector PWM voltage source inverter-fed induction motor was studied later. A rotor-oriented control system of induction machine was advanced, whose arithmetic was simple and convenient to operate economically. And then, according to the theory of photovoltaic pump system and the tracking theories, advantages and disadvantages of CVT(Constant Voltage Tacking) and TMPPT(True Maximum Power Point Tracking) used in maximum power point tracking of photovoltaic cells were analyzed. These methods were realized in vector-controlled induction motor. At last, combined with the traits of vector-controlled induction motor and photovoltaic pump system, the control diagram of system was designed.The simulation with both load and unload proved the scheme proposed in this paper could modulate the CVT voltage quickly and make it work stably. It showed the scheme was of the good characters both in load ability and dynamic operation.更多还原