2 results about "State variable" patented technology

A system and method for determining satisfiability of a bounded model checking instance by restricting the decision variable ordering of the SAT solver to a sequence wherein a set of control state variables is given higher priority over the rest variables appearing in the formula. The order for control state variables is chosen based on an increasing order of the control path distance of corresponding control states from the target control state. The order of the control variables is fixed, while that of the rest is determined by the SAT search. Such a decision variable ordering strategy leads to improved performance of SAT solver by early detection and pruning of the infeasible path segments that are closer to target control state.

The invention belongs to the field of model prediction control monitoring, and particularly discloses a process model mismatch detection method of a closed-loop model predictive control system. The method comprises the following steps: calculating a system residual value and an interference updating sequence of the control system based on input data and output data of the closed-loop model predictive control system and each transfer function in the control system; calculating a variance ratio of the system residual value to the interference updating sequence, taking the variance ratio as a quality index value of an actual process model in the control system, judging whether model mismatch exists or not based on the index value, and if the model mismatch exists, identifying all subspace matrixes of the control system by adopting a subspace identification method; and performing singular value decomposition on the subspace matrix corresponding to the state variable, calculating the ratioof the maximum singular value to the minimum singular value obtained by decomposition, and judging whether the actual process model is mismatched or not based on the ratio. According to the method, the actual mismatch model can be effectively detected and distinguished from various factors influencing the control performance only by utilizing the input and output data, and the method is efficientand reliable.