同塔四回输电系统可靠性分析

Reliability Analysis of Four-Circuit-on-Same-Tower Power Transmission Systems

同塔多回输电技术在输电走廊紧张或特殊地理环境下的应用越来越广泛,随着同塔多回输电系统电压等级的提高,同塔多回输电系统的运行可靠性对电力系统的安全、稳定、可靠运行产生重要影响。可靠性评估方法中传统的基于组合模型的可靠性分析方法存在模型复杂且计算量大的缺点,而基于分离模型的可靠性评估方法可以克服上述缺点。采用基于分离模型的可靠性评估方法,给出同塔四回及双塔四回输电线路的不同类型故障概率公式,并根据常见的线路失效频率和修复时间,对同塔四回及双塔四回输电线路的可靠性进行评估和比较,指出同塔四回输电系统可靠性低于双塔四回输电系统。

The multi-circuit-on-same-tower power transmission technologies are more and more often used in areas with scarce transmission corridor sources or with special geography environments. Along with the voltage grades increase of multi-circuit-on-same-tower power transmission systems, the reliability of these transmission systems has an important influence on power systems＇ security, stability and reliability. The traditional combined-model-based methods in reliability evaluation have the disadvantages of complex models and intensive computation. The reliability evaluation method based on separation models can overcome these disadvantages. Adopting the reliability assessment method based on separation models, this paper provided the probability formulas of different types of faults in four-circuit-on-same-tower transmission systems and four- circuit-on-two-towers transmission systems. And then according to the common faults＇ outage frequency and repair time, this paper evaluated and compared the reliability of four-circuit-on-same-tower power transmission systems and four-circuit-on-two-tower powers transmission systems. It is pointed out that the reliability of four-circuit-on-same-tower power transmission systems is lower than that of four-circuit-on-two-towers power transmission systems.