Title :
Disturbance observer based fully digital controlled PWM inverter for CVCF operation
Author :
Yokoyama, Tomoki ; Kawamura, Atsuo
Author_Institution :
Dept. of Electr. & Comput. Eng., Yokohama Nat. Univ., Japan
fDate :
9/1/1994 12:00:00 AM
Abstract :
A new approach for digital feedback control of a PWM inverter is proposed, in which an output DB (deadbeat) control is achieved combined with a disturbance observer. In the proposed scheme, the pole placements of the state observer and the disturbance observer are chosen separately. When the two observers employed the same pole placements, the experimental setup had a tendency to become unstable due to the detection error. By selection of the different pole placements, the disturbance observer quickly estimates the disturbance and feedforward disturbance cancellation is achieved. Then the state observer estimates the state variables at the next sampling instant, and the deadbeat controller is applied to the nominal system. This scheme has advantages in robustness in the practical application. From the view point of UPS applications, the advantages and disadvantages are discussed through simulations and experiments. Compared with other digital control laws, the superiority of the proposed control law is verified
Keywords :
digital control; feedback; invertors; poles and zeros; power engineering computing; pulse width modulation; state estimation; detection error; digital feedback control; disturbance observer; feedforward disturbance cancellation; fully digital controlled PWM inverter; output deadbeat control; pole placements; robustness; state observer; Control systems; Digital control; Feedback control; Observers; Pulse width modulation inverters; Robustness; Sampling methods; State estimation; State feedback; Uninterruptible power systems;
Journal_Title :
Power Electronics, IEEE Transactions on