摘要
明确指出常用的串联系统平均故障率计算公式可求得所有单重和多重故障对应的故障率之和。针对放射式和"闭环设计、开环运行"中压配电网,将影响负荷点年平均停电持续时间的多重故障分为串联系统多重故障和并联系统多重故障。对于串联系统多重故障,推导了考虑所有多重故障影响的系统年平均停电持续时间精确计算公式,而常用计算公式只含其一阶项,明确指出其k阶项并不对应于k重故障。另外,分析了并联系统多重故障对负荷点年平均停电持续时间的影响并推导了相关计算公式。采用典型配电网和可靠性参数的计算分析表明,一般情况下,串联系统年平均停电持续时间常规计算造成的误差以及并联系统多重故障对负荷点年平均停电持续时间的影响都较小。
It is clearly pointed out that the frequently used series system formula of average failure rate involves single and all multiple faults.For radial and 'closed-loop design,opened-loop operation'medium voltage distribution systems,the multifaults related to the reliability indices of a load point are divided into series and parallel ones.For series multi-faults,the precise formula of annual outage duration for series system has been derived with single and multiple faults being considered,which shows that commonly used formula contains only the first-order term of the precise formula;the k-order items of the precise formula cannot correspond to the annual outage duration caused by k-order faults.In addition,the effects of parallel multifaults on the annual outage duration of a load point are analyzed,and some related formulae are obtained.Examples using typical distribution networks and reliability parameters have verified that the error caused by commonly used annual outage duration formula of series system is small and parallel multi-faults generally have little impact on the annual outage duration of a load point.
出处
《电力系统自动化》
EI
CSCD
北大核心
2015年第12期69-73,共5页
Automation of Electric Power Systems
关键词
中压配电网
可靠性评估
多重故障
medium voltage distribution systems
reliability assessment
multi-faults
