关键词: 密封舱, 土压平衡, 多变量系统, 状态空间, 模型预测控制

Abstract: As control accuracy of Earth Pressure Balance（EPB） of pressure chamber lowly and its effect badly during tunneling process, an improved multivariable non-minimal state space model predictive control（IMNMSSPC） algorithm that is applied to the multi-point earth pressure balance control of head chamber is proposed. A transfer function matrix model is built through the step-response dates, and the construction of state space can be transformed into this model. This method introduces an adjustable factor to the cost function, and puts forward a new error compensation method in feedback correction, which can effectively reduce some errors produced through model mismatch. Predictive outputs are deduced with the theory of multi-step method. The earth pressure balance control model of shield machine takes the driving speed, the screw conveyor’s speed as inputs, and takes the pressure of head chamber as output. The algorithm can optimize the control variable. The application results show the proposed algorithm has more excellent control performance and a good tracking, disturbance rejection and robustness.

Key words:  head chamber, earth pressure balance, multivariable system, state space, model predictive control