To study the energy supply characteristics of gas-steam combined cycle at heavy refrigeration load

the combined cycle using SGT-600 gas turbine as the top cycle and heat recovery steam generator(HRSG) steam turbine as the bottom cycle is taken as the research object

the coupling models of gas turbine unit

HRSG-steam turbine system

double effect Li Br absorption chiller and electric chiller are established respectively by employing the EBSILON software. The energy supply characteristics of the coupling system under variable working conditions

such as total power generation efficiency

comprehensive energy utilization rate and net electric power saving rate

are compared under the condition of absorption refrigeration or electric refrigeration direct cooling. The results show that

the generation efficiency of the gas turbine decreases with the load rate of the gas turbine. At high cooling load

the generation efficiency and comprehensive energy utilization ratio of the steam turbine increase with the i load rate of the gas turbine. The comprehensive energy utilization ratio of the coupling system increases with the absorption cooling load. Under a certain load rate of the gas turbine

the comprehensive energy utilization ratio of the coupling system increases with the absorption cooling load. The net electric power saving rate increases with the rated cooling load. When the absorption cooling load reaches 20 MW

the maximum net electric power saving rate of the system can reach up to 6.20% at 70% load rate of the gas turbine unit. However

at lower rated cooling load

the effect of using absorption chiller is not as good as directly using electric chiller for direct cooling.