Characteristics Analyzing Of Gas Turbine Combined Cycle With Heat And Power Generation On Different Ambient Temperature And Load

With the increasing attention of China’s energy shortage,environmental pollution and the greenhouse effect,the combined cycle of gas turbine is highly anticipated by the energy industry due to its strength in high efficiency,environmental protection and fast changing of load.Furthermore,the combined cycle of gas turbine,applied in CHP,plays more important role in saving energy,reducing emission and improving energy utilization efficiency.In order to study the characteristics of gas turbine combined cycle CHP system on different condition,the modular modeling method,based on the geometric and design parameters of each components of the combined cycle unit,is adopted to modeling the components of combined cycle respectively,then coupling each model into entire combined cycle CHP model according to the relationship of parameters within components.The model is used to simulate the performance parameters of the GE9351FA combined cycle,the Mitsubishi M701F4 bottom cycle and the Siemens V94.3 bottom cycle,and the calculation results are in good agreement with the reference data.The model is also applied in analyzing heat and power range of three heat supplying mode of the Siemens V94.3 bottom cycle,and the heat-power characteristics figure is plotted to guide the formulating heat supplying plan of this HRSG according to different heat supplying target.For PG9351FA combined cycle CHP unit,the existing model,based on the compressor inlet flow and the condenser pressure changing with the temperature,is applied to study the influence of ambient temperature,heat and power load on gas turbine combined cycle CHP.The result shows that:at full load,the best combined cycle thermal efficiency among series of ambient temperature,mainly related to the condenser pressure changing law,is exist at Ta=8℃ in this case study.While operating at part load,the optimum ambient temperature of the bottom cycle performance is different in the high,middle and low load areas.At the heat supplying condition,the optimal heat supplying method is offered for the CHP unit when using the different index to evaluate.There is a critical value of heating load when the thermal performance index--the thermal efficiency and the general electricity consumption,is used to evaluate,the optimal heating method is opposite before and after the critical value.When economic efficiency is used as the evaluation index of CHP unit.,it is recommended that operating at high electric load under any heat load.