(1996) Reliability Evaluation of Power Systems一书中介绍的可靠性评估PJM方法有下面几句话: , U3 I+ z) p6 `) D: U1) ' {6 I4 z; C2 w& @ P1 p. M MIt is necessary in a practical system to first define an acceptable risk level in order to determine the maximum demand that a particular committed system can meet. 3 c( ?) x! f% _! Z# x
2)Consider, for example, that a risk of 0.001 is acceptable. If additional generation can be made available in System A within 1 hour, the required spinning reserve is only 30 MW and a demand of 170 MW can be supplied./ O2 o) Q) R9 }4 D& U, X; F
3) In practice an operator would use the PJM risk assessment method by adding, and therefore committing, one unit at a time from a merit order table until the unit commitment risk given by the generation model became equal to or less than the acceptable value for the demand level expected. $ `3 b7 {* q* L# }3 h
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原文2句的意思:假设系统允许的风险水平为0.1%。对系统A,若在1h内可以获得额外发电容量的支持,那么,A系统的旋备需求为30MW,可带负荷170MW。 & `; _; A9 f, H9 `- K* A 4 x% K3 L# h7 J我的疑问:" s& a( c9 r& w& M
从表5.2可见,A系统停运容量大于30的累积概率=运行容量小于170的累积概率=0.0915%,即运行容量大于170概率99.9%,此情形下系统可以带负荷170MW,若还可以获得额外30MW旋备,系统可带负荷就应该是200MW。 ) a1 {: `+ ^: n: y为何原文讲“170 MW can be supplied”? v8 Z2 G6 t* h2 b 3 J5 l: L. @+ a: \ I 6 F4 t6 f4 {- g& b$ d