Abstract: In order to improve the peak regulation capacity of combined heat and power（CHP） units and realize the thermoelectrolytic decoupling of the unit by using the heat network heat storage, the dynamic simulation models of a 350 MW cogeneration unit and its heat supply network system were established. The dynamic characteristics of the heat supply network and its heat users during the heat storage/release process and the influence of ambient temperature on the peak regulation capacity of the unit were studied. Results show that the lag time of the heat user increases with the increase of its distance from the first heat exchange station, and it is also directly affected by the heat load of itself and indirectly affected by the heat load of the other heat users. The relative heat storage/release power of the heat supply network first changes rapidly and then changes slowly after the change of the extraction steam flow rate. The temperature of the heat user changes approximately linearly, and its change rate increases with the increase of the variation range of the extraction flow rate, and the starting time of change is also advanced. The maximum peak regulation capacity of the unit increases slightly with the decrease of ambient temperature. When the ambient temperature decreases from 0 ℃ to-15 ℃, the peak regulation capacity of the unit increases from 23.8 MW to 29.7 MW. Increasing the heat storage time and the heat storage temperature and decreasing the heat release temperature can improve the peak regulation capacity of the unit.