摘要：Gas turbine power units,as an effective way to co.e with the severe challenge of renewable energy acco.modation in power grids,arouse the interest of power enterprises in the deep peak-load regulation *** co.mon alternative load-co.trol strategies including co.stant turbine inlet temperature(TIT)and co.stant turbine exhaust temperature(TET)regulations were taken into *** co.paratively investigate the part-load performance under these strategies,both mathematical and physical models were set up successively to serve as a validation and co.plementary to each *** the mathematical model of co.pressor with inlet guide vane(IGV),co.bustor and turbine,stage-stacking method based on blade average geometric parameter,energy co.servation and turbine stage model were adopted *** the physical model,design and off-design analysis were carried out based on GT PRO and THERMOFLEX *** simulation result of mathematical model validated the reliability of the physical *** on this,the influence of ambient temperature and different load-regulating strategies on the off-design performance of gas turbine power units was studied in *** results in the case of a PG 9351FA gas turbine show that the ambient temperature has a great impact on system performance,i.e.,every 5℃ increase in the ambient temperature produces a reduction of 3.7%in the relative full-load output and 1.1%in the relative efficiency respectively;when the gas turbine operates under co.stant TIT strategy,TET starts to rise till it reaches the maximum allowable value with the load rate decreasing,and IGV keeps at the minimum angle with both TIT and TET decreasing when the load rate is lower than 65%;when the gas turbine operates under co.stant TET strategy,TIT drops slightly at load rate of above 60%while both TIT and TET evidently decrease below 60%load rate operating along the co.stant co.rected speed line at the minimum allowable IGV opening;gas