Research on the Influence Mechanism of Different Depth Peak Shaving Transformation Methods on the Peak Operation Characteristics of Cogeneration Units and the Decoupling Transformation of Heat and Power in Northern Regions

Abstract

This study aims at the problem of insufficient peak shaving capacity of gas-fired cogeneration units under the background of the construction of the new power system in China, and systematically analyzes the influence mechanism of thermoelectric decoupling transformation technology and the peak operation characteristics at the top of the units. By constructing thermodynamic coupling models and dynamic response models, the improvement effects of technologies such as low-pressure cylinder resection and hot water storage tanks on peak shaving performance were quantitatively evaluated. The results show that the heat storage technology can significantly reduce the minimum load rate to 30% and increase the climbing rate by 4.5%/min. Combined with the actual operation characteristics in the northern region, a phased transformation strategy was proposed. It was recommended to adopt the combined mode of "mild transformation (operation optimization) + deep transformation (hot water storage tank)", and a two-part electricity price scheme (40 yuan /kW· month +0.55 yuan /kWh) was designed. It was verified that it could effectively stimulate the regulation potential of the unit while ensuring an investment return rate of 6%-8%.