Improving economy of low-load operation of thermal power units is an important energy-saving measure under the current situation of deep peak-regulating operation. This study introduces the principles and characteristics of five generalized regenerative systems. Taking a subcritical 300 MW wet and cold water unit as the research object

the evaluation models are established based on EBSILON commercial software. Parameter changes and energy-saving effect of five generalized regenerative technologies under different load rates of the unit are calculated and analyzed. The calculation results show that additional high pressure heater combined with external steam cooler system has the largest energy-saving effect. After the transformation

the coal consumption of the power generation can reduce by more than 1 g/(kW·h). The combined system of additional high pressure heater and hot air heater and the 3 rd extraction hot air heater system need to take targeted anti-abrasion measures. Additional high pressure heater system and the combined system of additional high pressure heater and hot air heater are beneficial to the operation of the denitrification system and the steady combustion of the boiler at low-load operation

which has a certain practicability under the urgent need of increasing the flexibility and deeper peakregulating capability of thermal power plants.