Research And Application On Interconnected Power System Of LFC With Renewable Energy Based On DMPC

With the increasing demand of electrical power and the deterioration of natural environment and the exhaustion of fossil energy,it’s urgent to find renewable energy.Solar and wind power are widely used for their clean,pollution-free and other advantages.Due to the volatility output of photovoltaic and wind power units,their integration into the power system will have a great impact on the frequency stability of power system.It is of great practical significance to explore a new method of load frequency control.A load frequency control method based on distributed model predictive control is proposed for the power system including thermal,wind and photovoltaic power units.Two structures are proposed for the way of renewable energy units participating in LFC.One is to treat large-scale wind power generating units and photovoltaic power generating units as separate generating areas and participate in the LFC of interconnected power systems together with thermal power units.The other is to treat the small-scale wind power and photovoltaic power units as the same control area as the conventional thermal power units,and the output of wind power and photovoltaic power units as disturbances in the system.Based on these two structures,mathematical models of each area are established respectively,and distributed model predictive controllers are designed to regulate the output of each generation unit.In the actual power system,there are two constraints in thermal power units,namely generation rate constraint and valve position constraint,along with the nonlinear constraints such as the pitch angle constraint of wind turbine,wind speed constraint and duty ratio constraint of photovoltaic power,they will have a great impact on the frequency stability of the whole system.Therefore,the constrained optimization problem is transformed into a quadratic programming problem.The system is simulated under different working conditions,and the simulation results show that the dynamic response performance of the system using this method is better.Figure 34;Table 3;Reference 45...