弱受端小电网安控切负荷措施与低频减载措施的配合方案  

Coordination Between Load Shedding for Safety and Stability Control and Under-frequency Load Shedding in a Small Weak Receiving Power System

作　　者：贾萌萌[1] 丁剑[2] 张建成[1] 吴丽华[2] 姜纯[3] 张启雁 

机构地区：[1]华北电力大学电气与电子工程学院,河北省保定市071003 [2]中国电力科学研究院,北京市100085 [3]国网青海省电力公司,青海省西宁市810008

出　　处：《电力系统自动化》2014年第1期74-81,共8页Automation of Electric Power Systems

摘　　要：基于电网低频紧急状态下系统频率变化特性的一般规律,详细分析了功率缺额扰动下的弱受端小电网暂态频率变化特点及其影响因素,如功率缺额、网内开机台数、负荷类型、故障地点及类型、切荷率、切负荷时间、电容器投切情况等,并给出了定性的理论公式推导。基于上述弱受端小电网频率变化特性的影响因素分析,针对小电网功率缺额扰动后存在的频率首摆下潜深度过大、持续时间较长的特点,提出了弱受端小电网安全稳定控制装置切负荷(简称安控切负荷)措施与低频减载措施的配合原则和具体配合方案:切负荷时间和切荷率的配合、装置动作出口配合。以西北某实际弱受端小电网为例,进行了仿真分析。仿真结果验证了所提配合原则的合理性和2种配合方案的可行性。Based on the general law of system frequency variation characteristics in low-frequency emergency state,frequency influencing factors in a small weak receiving power grid are analyzed at length during the disturbance due to power shortage, such as the quantity of power shortage,number of operating units,type of load,fault locations and types,load shedding time, load shedding ratio,whether to switch the capacitor or not etc.Then the theoretical derivation is qualitatively given.On the basis of analysis of the influencing factors in the above-mentioned small isolated power grid,in light of the characteristics of the excessively large dive depth and long duration of the frequency first swing,two coordination schemes of load shedding and under-frequency load shedding are proposed：load shedding time and load shedding ratio coordination and device outlets coordination.Take a real small weak receiving power grid in Northwest China as an example.Simulation results have verified the rationality of the coordination principle proposed and the feasibility of the two coordination schemes.

关 键 词：弱受端小电网 脱网运行 频率偏差 切负荷 低频减载 配合方案 

分 类 号：TM714[电气工程—电力系统及自动化]