海上风电场高压XLPE绝缘海缆可靠性评估的方法

Reliability Assessment Method of High Voltage XLPE Insulated Submarine Cable for Offshore Wind Farm

海上风电场需要对所使用的高压XLPE绝缘海缆方案的稳定性能以及故障损失风险进行评估,但目前国内外尚无应用在此领域中可靠性评估的实用方法。结合近海风电场海底电缆传输系统多种故障状态的特点,建立海底电缆的故障树模型和马尔可夫可修系统可靠性评估模型。最后,以国内某海上风电项目为案例进行分析,计算结果显示：三种方案的稳态无故障状态概率分别为97.5%、96.7%、97.4%;年传输容量期望计算值分别为1.9496×10^2、1.9673×10^2、1.9496×10^2MW;年故障损失成本期望值分别为2.51×10^3、1.77×10^3、2.61×10^3万元。根据计算结果可知,方案1无故障状态概率最大,但是三方案中,年传输容量和故障损失成本期望计算值对比分析,方案2（2回110 k V三芯高压XLPE绝缘交流钢丝铠装海缆）较优。实例表明,近海风电场高压XLPE绝缘海底电缆传输系统的可靠性评估需考虑其不同的故障状态,马尔可夫可修系统模型能够根据海缆传输系统不同的故障状态,从传输容量和故障损失成本的角度优化海缆的设计方案。

It is needed for offshore wind farm planning to estimate stability performances and failure loss risk of all transmission system schemes, which are composed by different high voltage XLPE insulated submarine cables, but there are not practical methods applied to this field domestic and overseas at present. In order to combine characteris- tics of different failure states for offshore wind farm submarine cable transmission system, a fault tree model and a markov repairable system model are build by fault tree theory and markov mathematical theory. At last, a ease of Chi- na offshore wind farm project is given, 3 design schemes show that： the unfauhy probability of 3 plan are 97. 5% , 96.7% ,97.4% ;expectation of transmission capacity and failure loss cost per year of 3 schemes are 1. 9496 ×10^2 , 1. 9673 ×10^2 ,1. 9496 ×10^2 MW and 2. 51 ×10^7 ,1.77 ×10^7 ,2. 61 ×10^7 RMB. According to the calculation result, the unfauhy probability of plan 3 is maximum among three plans, but plan 2 （with 2 circuit AC 110kV three-core high voltage XLPE insulated submarine cable） is the best plan though analyzing expectation of system transmission capacity and failure loss cost per year. Example analysis shows that it is needed to take different fault states of subma- rine cable transmission system for offshore wind farm. Based on different operating states, the markov repairable sys- tem model is useful to optimize offshore wind farm submarine cable design project, by contrasting expectation of sys- tem transmission capacity and failure loss per year.