【作者】 徐鹏来；

【导师】 王建华；

【作者基本信息】 江苏科技大学 ， 信号与信息处理， 2010， 硕士

【摘要】 太阳能作为一种高效无污染且可持续发展的新能源,受到了世界各国的广泛重视。光伏发电是太阳能利用的一个重要方面,而并网发电则是太阳能发电规模化的必然方向。光伏并网逆变器是光伏并网发电系统(GCPS,grid-connected PV generation system)的核心部件,本文主要针对分布式的单相光伏并网逆变系统,在其控制算法研究、系统仿真、软硬件设计等方面进行了深入探索。本文首先对光伏并网逆变系统的拓扑结构进行了分析,在对现有的几种单相并网逆变器电流跟踪策略进行比较分析的基础上,对无差拍控制方法进行了深入研究,探讨了采样,控制系统延时的问题。针对此问题,对系统的状态参数采用合适的方法进行预测,改善了因系统延时带来的影响,提高了并网电流的质量。仿真实验表明这种无差拍控制方式要明显优于目前较为常用的SPWM控制方式。对效率更高的单级式拓扑结构的光伏并网逆变器最大功率点跟踪(MPPT)算法进行了深入研究。在比较和分析了几种目前常用的最大功率点跟踪算法的基础上,选用最优梯度法作为本文的最大功率点跟踪策略,并对该算法进行了改进,使其稳定性得到了提高。本文同时从另外一个角度出发,根据单级式光伏并网逆变系统的结构和控制特点,提出了使用模糊自适应PID控制来调节光伏阵列工作电压的方案。仿真实验表明这种结构可以实现电压外环的高品质动、静态响应,而且具有较好的鲁棒特性,使最大功率点跟踪控制的响应速度和精度得到了进一步增强。本文对光伏并网逆变器的无功补偿和谐波抑制功能进行了研究,理解并吸收了瞬时无功理论,选择了合适的电流检测算法。将电流补偿控制和最大功率点跟踪控制结合起来,使光伏发电系统不仅仅能够向电网输送有功功率,同样可以补偿电网的无功和谐波分量。本文通过仿真验证了这种一体化控制思想的可行性。同时将补偿控制对最大功率点跟踪控制的影响做了仿真研究。本文最后对光伏并网逆变器的软硬件设计进行了研究,对光伏并网逆变器的拓扑结构设计、数字控制电路设计、功率元件计算给出了详细的设计要点和计算方法。同时对数字锁相环和PWM波产生方法进行了讨论,并给出了部分实验结果。最后对全文的工作进行了总结、并就今后的研究工作内容作了展望。更多还原

【Abstract】 Solar energy is a new energy which is effective, non-polluting for sustainable development. It has been received extensive attention around world. Photovoltaic power generation is an important aspect of solar energy utilization, and the photovoltaic grid-connected is inevitable direction of the large scale photovoltaic power generation. The grid-connected inverter is the core components of grid-connected PV generation system.(GCPS).This paper takes much effort in the control algorithm research, simulation, and hardware and software design of the single-phase photovoltaic grid-connected inverter.This paper analyzed the topology of GCPS. Through the compare of used current tracking strategies, this paper makes in-depth study on deadbeat PWM control method. To solve the effect of the delay, a deadbeat control algorithm is presented. Appropriate method was used to predict state parameter.This method improved the quality of grid-connected current. This algorithm is simulated and compared with SPWM control. The result of simulation indicates this deadbeat control algorithm is superior to traditional SPWM control.This paper takes much effort in the MPPT (Maximum power point tracking) method of single-stage GCPS which is more efficient. Through compare and analyzed of used MPPT method, A MPPT method based on gradient is proposed. And this paper improved gradient method on stability. This paper from another point of view, according to the structure and control characteristics of the single-stage photovoltaic power system, use fuzzy self-adaptive PID control to regulate voltage of PV array. Simulations results show that, this structure can make the voltage loop have a high quality dynamic and static response. And this structure which is robust, further enhance the responsiveness and tracking precision of the MPPT.This paper researches the GCPS which with reactive power and active filter. Comprehend and absorb the instantaneous reactive power theory. Select right harmonic and reactive power current detection algorithm. Combine the MPPT and current compensation control, so that the GCPS also can compensation the reactive power and harmonic in the grid. This paper use the MATLAB to verify the control theory, and research the affects which made by the compensation control to the MPPT control.At last, this paper researches the hardware and software design of GCPS. This paper carries out the details in the hardware topology, the control board design, the main power items calculation. And also discuss the DPLL and PWM generation method .Finally, the full work of the paper was summarized and research content on this subject in the future was made predicted.更多还原