Analysis and modelling of thermostatically-controlled loads

A general model of electric heating loads regulated by automatically-controlled thermostats is presented. The model is based on the equations of the thermal transients due to the thermostat operation. The power/voltage characteristic of a single load is obtained from the static analysis, showing its dependence on the most significant parameters of the thermostatic control, and the transient behaviour due to a step supply voltage decrease. The dynamic analysis is performed by simulating the response of a community of thermostatically-controlled loads with random initial conditions, subjected to step voltage variations. A theoretical justification of the behaviour of an aggregation of equal loads is given. Simulations are carried out to show the power response to voltage drops of different depth, up to the extreme situation of a load pick up which follows a temporary outage.

[1]  D. Hill,et al.  Modelling and identification of nonlinear dynamic loads in power systems , 1994 .

[2]  David J. Hill,et al.  Nonlinear dynamic load models with recovery for voltage stability studies , 1993 .

[3]  Fred Schweppe,et al.  Physically Based Modeling of Cold Load Pickup , 1981, IEEE Transactions on Power Apparatus and Systems.

[4]  Max D. Anderson,et al.  An Analytical Method for Quantifying the Electrical Space Heating Component of a Cold Load Pick Up , 1982, IEEE Transactions on Power Apparatus and Systems.

[5]  A. Gabaldon,et al.  Class of Models for Load Management Application and Evaluaton Revisited , 1992, IEEE Power Engineering Review.

[6]  R. E. Mortensen,et al.  Dynamics of heating and cooling loads: models, simulation, and actual utility data , 1990 .

[7]  V. Gerez,et al.  Development and validation of a physically-based computer model for predicting winter electric heating loads , 1995 .

[8]  C. W. Taylor,et al.  Load representation for dynamic performance analysis , 1993 .

[9]  R. E. Mortensen,et al.  A stochastic computer model for heating and cooling loads , 1988 .

[10]  James McDonald,et al.  Cold Load Pickup , 1979, IEEE Transactions on Power Apparatus and Systems.

[11]  R. Malhamé,et al.  Electric load model synthesis by diffusion approximation of a high-order hybrid-state stochastic system , 1985 .

[12]  J. D. Law,et al.  Measured and predicted cold load pick up and feeder parameter determination using the harmonic model algorithm , 1995 .

[13]  Thomas J. Overbye,et al.  Effects of load modelling on analysis of power system voltage stability , 1994 .