(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:* G4 b7 ?7 u/ n! y) o
1)+ [+ S' L' U; b; I, @ It 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. ) M7 J" c1 k1 m" F3 g! ^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. " y, q+ x0 _2 |0 W3) 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., Z( W5 F$ ?3 B8 |( C( \ `) @9 L% {
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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。- G7 R2 p5 w: j: P% e3 J
6 A/ V) x9 C* M5 s我的疑问:0 ]4 D. [/ E* S+ j
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。 6 c: t% t% O4 f M为何原文讲“170 MW can be supplied”? ; G% E" u+ J! {9 T' p8 `! o; \$ O4 z4 g" K; z y