The high proportion of new energy access leads to the scarcity of power system regulation capacity, and it is important to provide regulation capacity for the power system by reasonably regulating the electricity consumption of electric heating temperature-controlled loads. In this paper, in order to analyse the characteristics of the electric heating behaviour and the electric heating load's ability to participate in grid regulation, the differential equations of a typical room temperature change process are constructed first to establish the equation of state model of a two-input system, and then the state equations are discretised into difference equations according to the bilinear discretisation method for iterative solving. This paper analyses that the equivalent heat capacity and thermal resistance parameters of indoor air and wall will affect the temperature response time and the size of the required heating power, with the lowering of the outdoor temperature of a single household room, the average indoor warming time increases, the average cooling time decreases, the average daily power consumption increases, and the total power consumption of the whole community power also rises.