Study Of The Influence Of Reserve On Operating Reliability And Market Stability Under Power Market Environment

Sufficient reserve is indispensible for power system to satisfy the uncertain demand in operation, subject to the economic and reliability constraints of the system. Meanwhile, with deregulation of power industry, the stability of power market must be taken into account in arranging the reserve. The study of the influence of reserve on operating reliability and market stability can help to decide reasonale reserve in a practical way, to improve the economy and reliability of power system operation, and to design rational power market rules.A practical model for evaluating reserve in the multi-area power system is established in this dissertation. The model takes full consideration of the characteristics of the grid in which regional subsystems are relatively independent in normal operation and can support each other in emergency. A set of reliability indexes for each individual subsystem and the intact system is defined and a corresponding evaluation method is proposed. Test results for large-scale power systems proved that the model can realistically reflect the influence of reserve on operation reliability, and can correctly describe the relationship between the reliability of subsystems and whole system. The model can also calculate a reasonable cost allocation scheme for commonly-sharable reserve among subsystems.A modified quick sorting technique is proposed. By defining the minimum set of adjacent states and the replacement of neighboring states, it is proved that the maximum-probability states of the remaining states are definitely contained in the minimum set of adjacent states. Usable capability of units is defined to order the sequence of units. The probability and the importance of units are used to reduce the sampling variance. The application to practical systems shows that the convergence speed and calculation efficiency by using the modified sorting technique can be improved significantly.A dynamic model of power market incorporating influence of reserve is proposed. Based on eigenvalue techniques for differential-algebra equations, the influence of reserve on the market stability near the equilibrium point under small disturbance is studied. Based on the time-domain simulation method, the effect of reserve on market stability under large disturbance is analyzed. The research results are useful in designing market rules.