Predictive Direct Flux Control—A New Control Method of Voltage Source Inverters in Distributed Generation Applications

Abstract

Abstract:Voltage source inverters (VSIs) have been widely utilized in electric drives and distributed generations (DGs), where electromagnetic torque, currents and voltages are usually the control objectives. The inverter flux, defined as the integral of the inverter voltage, however, is seldom studied. Although a conventional flux control approach has been developed, it presents major drawbacks of large flux ripples, leading to distorted inverter output currents and large power ripples. This paper proposes a new control strategy of VSIs by controlling the inverter flux. To improve the system's steady-state and transient performance, a predictive control scheme is adopted. The flux amplitude and flux angle can be well regulated by choosing the optimum inverter control action according to formulated selection criteria. Hence, the inverter flux can be controlled to have a specified magnitude and a specified position relative to the grid flux with less ripples. This results in a satisfactory line current performance with a fast transient response. The proposed predictive direct flux control (PDFC) method is tested in a 3 MW high-power grid-connected VSI system in the MATLAB/Simulink environment, and the results demonstrate its effectiveness.

A Novel Power Sharing Strategy Based on Virtual Flux Droop and Model Predictive Control for Islanded Low-Voltage AC Microgrids

“…Moreover, the switching signals are generated by the direct flux control technique in a similar way to direct torque control and direct power control methods. Two hysteresis comparators are employed to produce the inputs of a look-up table, and subsequently, the proper switching vector is selected [26][27][28]. However, this control strategy is developed for an islanded microgrid with highly inductive line impedances.…”

Design Methodology of Novel PID for Efficient Integration of PV Power to Electrical Distributed Network

“…In order to improve the quality of the energy fed to the grid, other techniques have been developed. Among them, predictive direct flux control (PDFC) [11] study the behaviour of the flow that is the position and amplitude of the inverter flux in order to minimize the flux of the undulation and to improve their performance. Simulation results show the effectiveness of PDFC with a current THD of 4.09% compared to 12.15% of the conventional technique SDFC method.…”