Risk-based assessment and decision making of power system security in power market

In the new power market environment, the traditional security index will not meet economical requirement. Currently system operators are available of no well-designed tool and do decisions according their intuition or experience that doesn´t meet market requirement too. But research work is seldom about it and market operation of system security is limited to ancillary service. Combining with the research on China power market trends and based on risk, the paper will specially discuss transient security assessment, decision making on security. Firstly, based on risk assessment theory, it will mainly analyze a new transient security index and give out detailed assessment progress. The index consist transient insecurity probability and outcome to obtain balance between technology and economy. Based on conditional probability theory, it deduces the probability in response to probability distribution of system operation condition and fault in some system operation condition. Facility Method is introduced to evaluate the risk assessment. Secondly, risk decision theory about dynamic security is put forward. An utility function decision process-a stochastic optimization method is formulated to compute the optimal initial operation state. Aiming at the deficient current decision level of system operator in Jiangsu Province electrical company, the decision-making strategy well balanced technical security and economy.