新电改背景下售电公司的购售电策略及风险评估

随着我国电力体制改革的深入和能源利用技术的发展,售电公司日渐成为多能量市场的主体。开展多时间尺度购电、合理配置各类能源购电比例及提供差异化售电合同是提高售电公司经营效益和降低风险的核心策略。综合考虑中长期市场及现货市场、可再生能源、分布式电源及储能设备等因素建立多时间尺度的多能量市场购电模型,并基于差异化合同建立售电模型;采用概率场景描述可再生能源出力及负荷预测的随机性,并以条件风险价值作为购售电风险评估指标;通过最大化收益及最小化风险损失最终确定购售电策略。算例分析结果表明,最大程度采购分布式电源电量、科学安排储能设备充放电及提高可再生能源出力预测精度,均能增加售电公司收益,同时减低购售电风险。

Power Trading Strategy and Risk Assessment of Electricity Retailing Company Under Power System Reform

With improvement of power system reform and development of energy technology in China, electricity retailing companies become the main bodies in multi-energy market. With respect to risk reduction and management efficiency improvement, electricity purchasing with multitime-scale method, allocation optimization of various electricity purchasing proportions and differentiated selling contract are of central importance. In consideration of the multi-time-scale electricity purchasing model based on medium-and-long-term market, spot market, renewable energy, distributed generation, energy storage equipment, and the electricity selling model based on differentiated contract, this paper describes the uncertainty of load forecast and renewable energy output with scenario analysis method. Furthermore, the electricity business decision and risk assessment are made under guidance of conditional value-at-risk(CVaR), regarded as risk evaluation index. Numerical results demonstrate that maximum utilization of distributed generation and scientific control strategy of energy storage equipment along with improvement of prediction accuracy of renewable energy output can assist electricity retailing company in risk prevention and risk management, thus improving conditional risk earning and business competitiveness.