Research On Optimal Control Strategy Of Cell Voltage In Aluminum Electrolysis Process Based On State Comprehensive Evaluation Model

With the increasingly prominent of energy issues,energy-saving production has become the direction for enterprises to achieve sustainable development.During the aluminum electrolysis production,DC power consumption can be effectively reduce by reducing cell voltage.But the cell voltage can not be directly controlled.Therefore,an optimal control strategy for cell voltage based on cell state comprehensive evaluation model is proposed in this paper.Firstly,a cell state evaluation model based on adaptive fuzzy C-means clustering algorithm(FCM)is established.From a global point of view,reflecting the energy balance,material balance and stability,a comprehensive index model of cell state is established.And then,the cell state samples are divided into three classes by an adaptive FCM algorithm.According to the comprehensive index,the different class is evaluated into three categories:excellent,good and bad.Experiments with actual production data show that the model can effectively evaluate the cell state and has good accuracy.Then,for the excellent cell state,the optimal control model of cell voltage is established with the production conditions as constraints and the lowest cell voltage as the objective,which provides a control scheme for energy-saving.The cell voltage prediction model is established by least squares vector machine(LSSVM)which was optimized by ant lion algorithm(ALO).Then the optimal cell voltage are solved by ALO.Experiments show that the cell voltage prediction model has good accuracy,and the optimal cell voltage value and corresponding production parameters can be solved,which have good energy-saving effect.Then,for the good cell state,the optimal setting model of cell voltage is established with the actual production operation requirements as constraints,optimal cell voltage and cell state as the objective.In this model,the cell state prediction model is built by an autoregressive moving average-fuzzy neural network(ARMA-FNN),and the optimal settings value is obtained by multi-objective ant lion optimization algorithm(MOALO).The simulation results show that,after the optimal setting value is sent to the control system,the cell state would gradually stabilize and develop to the optimal state.Finally,the proposed method is validated on the platform of aluminum electrolysis operation control system.Experiments show that,if the parameters of the cell voltage optimization model are sent to the control system,the cell voltage can be controlled in the optimal range and achieve the purpose of energy saving.If the cell state deteriorates,the operation parameters are adjusted accordingly,the cell state can gradually become better.