光伏发电系统的MPPT与并网控制策略研究
发布时间：2018-08-06 14:37
【摘要】：全球不可再生的化石能源储存量的有限性和人类社会延续发展对能源的无限需求的矛盾愈发激烈,这一矛盾将会导致全球经济发展减速和不平衡。在这样的世界能源形势的大背景下,利用可再生能源成为解决这一矛盾的有效途径。太阳能作为可再生能源的一种,其开发和利用受到了全世界的关注。光伏发电是充分利用太阳能的有效途径,目前国内大部分光伏发电都允许并网运行更是为未来我国光伏发电的发展提供了条件。光伏电池的最大功率点跟踪(MPPT)影响着光伏系统的发电效率,光伏逆变器的并网控制方法关系光伏系统的稳定性。这两大关键技术直接影响整个光伏发电系统的工作效率和稳定性,本文将主要围绕这两方面展开研究。首先,本文对光伏阵列的功率输出特性曲线进行了建模仿真分析。MPPT的目标是保持光伏阵列输出电压一直保持在最大功率点处,本文对目前常用的一些用于局部阴影情况下的最大功率点跟踪控制方法进行了比较,重点分析了基于粒子群算法(PSO)的MPPT控制方法,并提出了一种基于改进的模拟退火粒子群算法的最大功率点跟踪控制方法,将模拟退火算法思想融入到粒子群算法中,改善粒子的探索能力,提升了最大功率点跟踪算法的收敛速度和精确性。其次,阐述了光伏发电系统的并网控制方法的原理和目标,对目前常用的几种控制方法的优缺点进行了比较。本文针对带本地负载的并网发电系统产生的谐波污染和无功消耗问题,提出了一种比例积分(PI)与比例谐振控制(PR)相结合的新型复合并网控制策略,利用PI控制对逆变器的输出的并网电流进行控制,利用PR控制算法控制逆变器对本地非线性负载进行谐波抑制。该控制策略提高了光伏并网逆变器的利用率,改善了公共连接点处的电能质量。通过实验仿真,该控制策略可以在向电网输出有功功率的同时实现对本地负载的无功和谐波补偿。最后,本文具体阐述了基于DSP TMS320LF2812芯片控制的单相光伏并网发电装置的控制系统,包括SPWM的软件实现方法、频率与相位差的检测方法、软件锁相技术的实现等。并在此基础上制作了一台单相光伏并网发电装置,并对装置进行了实验测试。
[Abstract]:The contradiction between the limitation of the global non-renewable fossil energy storage and the infinite demand for energy from the continuous development of human society will lead to the deceleration and imbalance of global economic development. Under the background of the world energy situation, the use of renewable energy has become an effective way to solve this contradiction. Solar energy as a renewable energy, its development and utilization has attracted worldwide attention. Photovoltaic power generation is an effective way to make full use of solar energy. At present, most photovoltaic power generation in China is allowed to run grid-connected, which provides conditions for the future development of photovoltaic power generation in China. The maximum power point tracking (MPPT) of photovoltaic cells affects the efficiency of photovoltaic system. The grid-connected control method of photovoltaic inverter relates to the stability of photovoltaic system. These two key technologies directly affect the efficiency and stability of the whole photovoltaic system. First of all, in this paper, the power output characteristic curve of photovoltaic array is modeled and simulated. The goal of MPPT is to keep the output voltage of photovoltaic array at the maximum power point. In this paper, some commonly used methods for maximum power point tracking control under local shadow are compared, and the MPPT control method based on particle swarm optimization algorithm (PSO) is emphatically analyzed. A maximum power point tracking control method based on improved simulated annealing particle swarm optimization algorithm is proposed. The idea of simulated annealing algorithm is integrated into particle swarm optimization algorithm to improve the ability of particle exploration. The convergence speed and accuracy of the maximum power point tracking algorithm are improved. Secondly, the principle and goal of grid-connected control method of photovoltaic power system are expounded, and the advantages and disadvantages of several common control methods are compared. Aiming at harmonic pollution and reactive power consumption caused by grid-connected power generation system with local load, a new hybrid grid-connected control strategy combining proportional integral (PI) and proportional resonance control (PR) is proposed in this paper. Pi control is used to control the grid-connected current of inverter output, and PR control algorithm is used to control the harmonic suppression of local nonlinear load. The control strategy improves the utilization rate of photovoltaic grid-connected inverter and improves the power quality at common connection points. Through experimental simulation, the control strategy can realize reactive power and harmonic compensation of local load while outputting active power to power grid. Finally, this paper describes the control system of single-phase photovoltaic grid-connected generation device based on DSP TMS320LF2812 chip, including the software realization method of SPWM, the detection method of frequency and phase difference, the realization of software phase-locked technology and so on. On this basis, a single-phase photovoltaic grid-connected power generation device is made, and the device is tested experimentally.
【学位授予单位】：长沙理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM615
本文编号：2168043
[Abstract]:The contradiction between the limitation of the global non-renewable fossil energy storage and the infinite demand for energy from the continuous development of human society will lead to the deceleration and imbalance of global economic development. Under the background of the world energy situation, the use of renewable energy has become an effective way to solve this contradiction. Solar energy as a renewable energy, its development and utilization has attracted worldwide attention. Photovoltaic power generation is an effective way to make full use of solar energy. At present, most photovoltaic power generation in China is allowed to run grid-connected, which provides conditions for the future development of photovoltaic power generation in China. The maximum power point tracking (MPPT) of photovoltaic cells affects the efficiency of photovoltaic system. The grid-connected control method of photovoltaic inverter relates to the stability of photovoltaic system. These two key technologies directly affect the efficiency and stability of the whole photovoltaic system. First of all, in this paper, the power output characteristic curve of photovoltaic array is modeled and simulated. The goal of MPPT is to keep the output voltage of photovoltaic array at the maximum power point. In this paper, some commonly used methods for maximum power point tracking control under local shadow are compared, and the MPPT control method based on particle swarm optimization algorithm (PSO) is emphatically analyzed. A maximum power point tracking control method based on improved simulated annealing particle swarm optimization algorithm is proposed. The idea of simulated annealing algorithm is integrated into particle swarm optimization algorithm to improve the ability of particle exploration. The convergence speed and accuracy of the maximum power point tracking algorithm are improved. Secondly, the principle and goal of grid-connected control method of photovoltaic power system are expounded, and the advantages and disadvantages of several common control methods are compared. Aiming at harmonic pollution and reactive power consumption caused by grid-connected power generation system with local load, a new hybrid grid-connected control strategy combining proportional integral (PI) and proportional resonance control (PR) is proposed in this paper. Pi control is used to control the grid-connected current of inverter output, and PR control algorithm is used to control the harmonic suppression of local nonlinear load. The control strategy improves the utilization rate of photovoltaic grid-connected inverter and improves the power quality at common connection points. Through experimental simulation, the control strategy can realize reactive power and harmonic compensation of local load while outputting active power to power grid. Finally, this paper describes the control system of single-phase photovoltaic grid-connected generation device based on DSP TMS320LF2812 chip, including the software realization method of SPWM, the detection method of frequency and phase difference, the realization of software phase-locked technology and so on. On this basis, a single-phase photovoltaic grid-connected power generation device is made, and the device is tested experimentally.
【学位授予单位】：长沙理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM615
【参考文献】
相关硕士学位论文 前1条
1 郝立颖;太阳能光伏发电系统设计及供电系统优化方法研究[D];东北大学 ;2008年
，本文编号：2168043
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