三相并网变流器在电网暂态故障情况下的安全运行与控制研究

项目名称： 三相并网变流器在电网暂态故障情况下的安全运行与控制研究

项目编号： No.51277191

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 电工技术

项目作者： 杜雄

作者单位： 重庆大学

项目金额： 85万元

中文摘要： 随着新能源发电的快速发展和大规模应用，三相并网变流器得到了广泛的应用。电网要求并网变流器在电网暂态故障情况下不仅能持续并网运行，而且还能对电网故障进行支撑，以利于故障后的电网恢复。但电网暂态故障情况下，并网变流器面临负序电流、谐波、直流母线电压波动，以及过压过流等一系列问题，变流器自身的安全运行受到挑战。为了实现故障时并网变流器的安全运行并对电网进行支撑，本项目将研究电网暂态故障对并网变流器的安全运行影响机理，描述故障情况下并网变流器的安全运行能力，为故障时对电网支撑提供理论依据。提出瞬时功率缓冲器的概念，采用超级电容实现，通过研究优化的控制策略来实现并网变流器在对称和不对称故障情况下的统一控制，解决直流母线电压波动和二倍工频纹波的问题，实现暂态故障情况下变流器的安全运行和对电网支撑的统一。本项目的研究将有助于增强并网变流器的故障穿越能力，并实现对电网故障的支撑，拓展并网变流器的功能。

中文关键词： 并网变流器；电网暂态故障；安全运行；优化控制策略；

英文摘要： With the rapid development and large-scale application of the renewable energy, the associated grid-tied three-phase power converter has also been widely used. The grid not only require the grid-tied power converters have the fault ride-through ability, but also can support the grid to facilitate fault recovery under grid transient fault conditions. But under the fault condition, the grid converter faced with the negative-sequence grid current, harmonic current, the dc bus voltage fluctuations, as well as over voltage and over current issues which will affect the safe operation of the converter. In order to realize the fault ride-through capability and facilitate fault recovery, this project will study mechanism of the safe operation problems converter under grid transient fault condition, and describe the safe operation capability of the converter to provide a theoretical basis for gird support. The concept of instantaneous power buffer which uses the super-capacitor is proposed. Through studying optimal control strategy to achieve the unified control of the grid-tied converter in the case of symmetrical and asymmetrical fault, and solve the dc bus voltage fluctuations and the second-order voltage ripple problems in the dc bus, to achieve the unification of the safe operation and grid support of the grid-tied t

英文关键词： grid-connected converter；grid transient fault；safe operation；optimal control strategy；