S.-H. Zhang’s scientific contributions

Distribution companies are faced with the trade-off between benefit and risk when they purchase energy under electricity market environment. In terms of conditional value at risk as the measuring index for market risk, a purchasing model based on portfolio theory is presented, in which the object function is to minimize the portfolio loss among the wholesale market, bilateral contract market, distributed generation (DG) and interruptible load (IL). The impacts of DG and IL on purchasing portfolio loss are addressed. Then the effects of the cost of DG and the compensation price of IL on portfolio allocation are investigated. The results show that IL and DG can effectively reduce the purchasing losses of distribution companies, and with the increase of the implementing cost of IL and the generating cost of DG, the effect of risk aversion gradually weakens. Finally, a numerical example is used to illustrate the validity of the proposed method.