(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:; r$ D9 _ X* u$ a4 @
1) ( k" u& _8 K9 k( q* q7 C# \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. 3 _: d* L7 J Q2)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. d6 y5 E, o9 h" ?" D6 |* {
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. 7 `, P/ [* ?+ ?5 f5 O
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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。 0 B! x! m+ D4 ?3 x, b- ` m ( y: R+ M1 V" @0 ~4 o. t我的疑问: 6 e( R% \) Q% N+ n* v9 |& x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。 + c y1 p* l3 D/ F' \; u为何原文讲“170 MW can be supplied”?4 N5 I% F0 ^* ]& e