초록 ▼

A weigh feeding system using a stochastic controller wherein the weight of material and the position of a material discharge actuator are sensed, and an estimate of the mass flow state of the material being discharged is created by use of a Kalman filter process. Plant noise processes and measuremen

A weigh feeding system using a stochastic controller wherein the weight of material and the position of a material discharge actuator are sensed, and an estimate of the mass flow state of the material being discharged is created by use of a Kalman filter process. Plant noise processes and measurement noise processes, which affect the measured weight and actuator position signal, are modeled as stochastic processes and are used, in combination with the sensed weight and actuator position signals, to calculate the estimated mass flow state. The noise models are modified to account for disturbances. The estimated mass flow state signal is used to calculate a motor feedback signal which, in turn, is used to control the speed of the discharge apparatus. In this manner, the mass flow of the material actually being discharged is driven to a desired mass flow with minimum error variance in the presence of unavoidable plant and measurement noise. Self-tuning of the stochastic controller is employed to accurately determine parameters of the plant noise and measurement noise processes, and to compensate the controller for control dynamics. Feedback control tuning is also employed to monitor the set-point error in order to achieve quick response while maintaining smooth steady-state set point control.

대표청구항 ▼

A weigh feeding apparatus comprising: means for storing a quantity of material; means for discharging material from said means for storing, including a material discharge actuator; means for sensing a weight of said quantity of material or a weight of material being discharged; means for detecting a

A weigh feeding apparatus comprising: means for storing a quantity of material; means for discharging material from said means for storing, including a material discharge actuator; means for sensing a weight of said quantity of material or a weight of material being discharged; means for detecting a position or a velocity of said material discharge actuator; means, including a model of at least one noise process which causes said sensed weight to differ from an actual weight of stored material or an actual weight of material being discharged, for estimating a first rate of material being discharged according to said sensed weight; means, including a model of at least one noise process which causes said detected position or velocity to differ from an actual position or velocity of said material discharge actuator, for estimating a second rate of material being discharged, according to said detected position or velocity of said material discharge actuator; means for combining said first and second rates to produce an estimated total rate of material being discharged; and means for controlling said material discharge actuator in accordance with said estimated total rate of material being discharged, to discharge material from said means for storing at a desired material discharge rate.