A method and system for improving the flexibility of gas turbine combined heating and cooling

Abstract

The invention discloses a method and system for improving the electricity-heat-cold united supply flexibility of a gas turbine. During the trough of an electric load, a certain proportion of compressed air is extracted from the rear portion of an air compressor of the gas turbine and is then cooled for the first time, compressed and cooled for the second time, and then high-temperature air entersan air storage tank to be stored, so that the generation power of a unified supply system is reduced. During the peak of the electric load, the high-temperature air in the air storage tank is heated by a heater and is then mixed with low-pressure air extracted from the middle of the air compressor to form medium-pressure air, and then the medium-pressure air enters a combustion chamber of the gasturbine to participate in acting, so that the generation power of the unified supply system is improved. According to the method and system improving the electricity-heat-cold united supply flexibility of the gas turbine, electricity-heat-cold united supply of the gas turbine and compressed-air energy storage are combined so that the regulation range of the heat-to-electricity ratio of the electricity-heat-cold united supply system of the gas turbine can be effectively widened, and the influence of electricity-heat-cold united supply of the gas turbine on the peak-trough difference of a powergrid is reduced; and the method and system have the advantages that the system is simple, the comprehensive heat efficiency is high, and operation and maintenance are easy.

Description

technical field [0001] The present disclosure relates to a method and a system for improving the flexibility of a gas turbine electric heating and cooling cogeneration. Background technique [0002] The statements in this section merely provide background information related to the present disclosure and do not necessarily constitute prior art. [0003] Natural gas is a precious resource, how to use it rationally is the focus of common attention of the government and the energy industry. [0004] Gas turbine electricity, heating and cooling combined power supply is a comprehensive energy system configured close to the user side. Based on the principle of energy cascade utilization, it can provide electricity, heat and cooling loads at the same time, thereby effectively increasing the primary energy utilization rate to more than 80%. In recent years, gas turbine combined heating and cooling technology has developed particularly rapidly. There are dozens of domestic construct...

AI Technical Summary

Problems solved by technology

However, the characteristics of the gas turbine itself determine that the heat-to-power ratio of the cogeneration system is not high, and it is difficult to realize the decoupling adjustment of electricity and heat output. When the power generation is reduced, the heat supply capacity will often be reduced; secondly, the gas turbine part The load performance is poor, and the heat-to-power ratio is adjusted by changing the load. Compared with the combined cycle power generation (50% power supply efficiency) + gas boiler heating + electric cooling distribution system, the combined power system is often not energy-saving; The life characteristics of walking at night and the difference in load demand of different types of users lead to huge peak-to-valley load differences in power grids in different periods or seasons, as well as wide-range fluctuations in heat-to-power ratio, and the peak heat consumption is often inconsistent with the peak power consumption , which is a global problem

In contrast, the heat-to-power ratio of gas turbine combined heating and cooling is usually between 1-1.5, which cannot meet a wide range of heat and electricity load fluctuations, and increases the peak-to-valley variation of the power grid

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