新能源汇集区域次同步振荡控制防线的研究与应用

Ｒesearch and Application of Subsynchronous Oscillation Control Line for New Energy Centralized Area

摘要:

随着国家对新能源发展的大力支持，风电、光伏装机规模呈现快速增长，尤其是风能、太阳能资源丰富的区域， 新能源呈现集中式开发。但是新能源汇集区域多位于电网末端，系统短路电流水平低，同时新能源均通过电力电子 装置并网，从而引发了次同步振荡问题。随着电网中电力电子化元件大量采用，元件自身、元件与元件之间相互协调 影响作用进一步凸显，次同步振荡问题进一步恶化。因此在次同步振荡机理尚不明确的前提下，开展次同步控制防 线研究，抑制和隔离次同步振荡发生。开展了次同步振荡原因分析; 结合现有的电网防御体系，建立新能源汇集区域 次同步控制防线，提出了基于机组模态频率的次同步振荡控制系统; 对某一次同步振荡分析，验证了所提出的次同步 控制系统的正确性。研究成果为新能源汇集区域的次同步振荡控制提供了技术方案，保障了新能源汇集区域电网安 全稳定运行。

Abstract:

With the country's strong support for the development of new energy，the installed capacity in wind power and photovoltaic has a rapid growth，especially in the areas with abundant wind energy and solar energy，new energy is presented a centralized development． However，most of the new energy centralized areas are located at the end of power grid，and its short － circuit current level is low，while the new energy is integrated to power grid through power electronic devices，which causes a subsynchronous oscillation problem． With the large number of power electronic components used in power grid，the component itself，and the coordination effect between the components are further highlighted，and the problem of subsynchronous oscillation is further deteriorated． Therefore，for the premise that subsynchronous oscillation mechanism is not clear，the research of subsynchronous control line is carried out to suppress and isolate subsynchronous oscillation． The analysis on the causes of subsynchronous oscillation is carried out too，the subsynchronous oscillation control system based on modal frequency of the unit is proposed combining with the existing grid defense system，and the subsynchronous control line for the new energy centralized area is established． And then a synchronous oscillation is analyzed to verify the correctness of the proposed subsynchronous control system． The research results provide a technical scheme for subsynchronous oscillation control in the new energy centralized area，which may ensure the safe and stable operation of power grid in the new energy centralized area．