不同定价方式下电力拍卖市场运行特征的比较研究(二)仿真结果及其分析

以IEEE可靠性测试系统的数据为基础，对不同定价规则的电力拍卖市场进行了基于智能代理的仿真。结果表明：①在统一出清电价(UCP)和按报价支付(PAB)的电力市场，减少发电厂商的市场份额可以削减发电厂商的市场力，但条件是系统要有足够的备用容量；如果负荷需求接近总可用容量，即使最大的发电厂商的市场份额只有11．4％时，其电力市场的价格也会远远偏离其边际成本价格。②在PAB电力市场，市场均衡状态的总购电费用以及平均价格两方面几乎和UCP电力市场电价没有差别，甚至还要高于UCP电力市场的均衡价格，因此，使用PAB的方法很难达到抑制电价飞升的目的。③在当量电价(EVE)的电力市场，发电厂商几乎没有策略空间，所有的发电厂商都自动按照其成本报价，而且对于各种情况都具有相当稳定的表现。EVE还提供了一种独特的容量投资自动补偿机制，使得在发电生产成本存在规模经济性时，发电厂商可以得到合理的补偿。而在UCP和PAB电力市场，一方面会出现发电厂商报高价的现象，另一方面还会出现部分发电厂商负利润的情况。所有结果表明EVE具有优良的市场特征，对于发电容量相对紧缺，不变成本不可忽视的中国电力工业现状，采用EVE不失为一个明智的选择。

COMPARISONS AMONG PRICING METHODS IN POOL-BASED ELECTRICITY MARKET BY AGENT-BASED SIMULATION:Part Two Results and Analysis

The agent-based simulation results based on IEEE reliability test system data were presented in this paper. The results show that: (1) Decreasing the generator firm's capacity share of the total available capacity is important for restraining the generator firm's market power in the electricity market with Uniform clearing pricing (UCP) method and pay as bid pricing (PAB) method, However, the condition is the adequate capacity reserve. In other words, UCP and PAB are inapplicable for the capacity shortage electricity market. (2) The PAB pricing method cannot restrain the generator firm's market power. Some time the market power in PAB auction may be higher than that in UCP auction. (3) When the electricity value equivalent (EVE) pricing method is employed in market pricing, there exists very small room for a power supplier to lift up the market price by his strategic bidding and the market becomes robust in some sense. When there are economics of scale in generation market, EVE pricing method provides an intrinsic and reasonable mechanism to compensate the capacity investment automatically. However in UCP auction there are some firms bearing the negative profits while bidding the price more than their marginal cost. All these results show that there is excellent market characteristic in the electricity market with EVE pricing method and it is an advisable choice for China electricity market.