Research On Multi-time Scale Power Grid Voltage Model Predictive Control Method Considering Reactive Power Replacement

The transformation of the global energy structure and the strong uncertainty caused by the high proportion of new energy sources such as wind power and photovoltaics connected to the grid have brought great challenges to grid voltage control.Most of the traditional voltage predictive control models are single time section control models based on a single time point,which are more practical in long time scale voltage control.In the short-time-scale rolling optimization,it is necessary to consider the climbing constraints of the dynamic reactive power compensation equipment,that is,the constraints of its single adjustment amount,the single-time section control model algorithm lacks foresight,the overall voltage control accuracy is not high,and the stability is poor;Moreover,it occupies a large amount of dynamic reactive power resources in the steady-state operation of the power grid,and it is difficult to meet the requirements of grid voltage security and stability control.In view of this,this paper proposes a multi-time scale grid voltage model predictive control method considering reactive power replacement.First of all,considering the traditional model predictive control method is more dependent on the accuracy of the prediction model for pressure regulation,the pressure regulation accuracy of the control model is improved without increasing the complexity of the model.In this paper,the error feedback correction link of the model predictive control method is improved,using the historical vo ltage control deviation information of the node,and adopting the adaptive dynamic error feedback coefficient method,so that the predicted voltage can co ntinuously approach the actual value of the voltage,and the voltage control accuracy is improved.Secondly,a dual-time-scale voltage control model is established.The long-time-scale voltage control layer arranges static reactive power compensation equipment to participate in voltage regulation,and adopts the single-time section voltage control based on the improved chaotic black hole particle swarm algorithm as the optimization kernel.The short-time-scale voltage control layer arranges dynamic reactive power compensation equipment to participate in voltage regulation,and adopts a rolling optimization model based on improved model predictive control.The regional power grid after reactive power and voltage partition is used as an example to verify the feasibility and advancement of the voltage control model proposed in this paper.Finally,considering that the voltage control model occupies a large amount of dynamic reactive power voltage regulation resources in the steady-state operation scenario of the power grid,it is not conducive to the safe and stable operation of the power grid.In this regard,this paper proposes a dynamic and static reactive power replacement mechanism.The mechanism is transplanted into the short-time-scale rolling prediction window,and can judge whether the replacement starts or exits according to the reactive power compensation plan in the prediction window,and completes the reactive power replacement in real time.The reactive power replacement resets the dynamic reactive power and static reactive power compensation plans in turn according to the voltage regulation sen sitivity sequence of each node.Through the interactive control of dual time scales,sufficient dynamic reactive power resources are reserved for the power grid under the premise of ensuring the accuracy of voltage control.