The absorption heat pump(AHP) compensation heating method is an important way to decouple heatpower constraints of combined heat and power(CHP) units. In order to ensure the safe and stable operation of CHP units with AHP system

this paper analyzes the principle and characteristics of the AHP compensation heating system

and proposes a calculation method for the safe operation area of a CHP unit with AHP system. In this method

the safety area of extraction type heat supply unit after back pressure lifting is firstly calculated. Then

considering the effect of the absorption heat pump compensation heating on the heating safety zone

the calculation method of the absorption heat pump heating safety zone is given

based on the design parameters of the absorption heat pump. Moreover

it is compared with the safety zone of the original exhaust heat supply unit. A 330 MW steam extraction heating unit was used for comparative verification. The results show that

the AHP compensation heating system can greatly improve the heating decoupling ability

electrolytic decoupling ability and deep peaking ability of the CHP unit. However

the demand for back pressure in the normal operation of the AHP will increase the minimum power output of the unit slightly.