A Stationary Reference Frame Current Control Algorithm for Improvement of Transient Dynamics of a Single Phase Grid Connected Inverter

Abstract

This paper proposes a stationary reference frame current control algorithm for a single-phase grid-connected inverter (GCI) for improvement of transient dynamic performance. Disturbance, i.e., grid voltage in a target system, is estimated using a stator current observer, and the estimated disturbance is applied to a current controller for implementation of disturbance rejection control (DRC). In the proposed current control algorithm, the disturbance rejection control algorithm is applied to reduce the overcurrent occurring in the single-phase grid-connected inverter when grid faults happen. In this paper, the AC phase current of a single-phase inverter is controlled, instead of the current vector, which is a DC signal. To compensate for the drawbacks of controlling the AC phase current, such as phase lag and steady-state error, command feedforward control is also applied in the proposed control system. The proposed control algorithm is mathematically derived and represented in transfer functions and implemented via simulation and experiment.

Emerging Technologies in Power Systems

“…The proposed active phase controller is only used the phase angle of lower than 10 • in each connection point and required a small power capacity. In addition, the paper in [5] also introduces the control method grid-connected for single-phase inverter system, entitled "A Stationary Reference Frame Current Control Algorithm for Improvement of Transient Dynamics of a Single Phase Grid Connected Inverter". The current control method is proposed to enhance the transient dynamic performance of the inverter system.…”

Highly Accurate Digital Current Controllers for Single-Phase LCL-Filtered Grid-Connected Inverters

“…At this point, it is convenient to define the following constant: (15) In this way, the parameters of the current controller in s-domain are given by the following equations: C 2 = must be de f ined (100n f or example) (16)…”

A Current Control Algorithm to Improve Command Tracking Performance and Resilience of a Grid-Connected Inverter

“…In [12,13], CFFC is applied to a PI controller to compensate the drawbacks of controlling AC signals, but it was used for voltage control for in a single-phase Uninterruptible Power System (UPS) system. The CFFC is applied to the stationary reference PI controller to improve transient dynamic performance of a GCI current control system but it is limited to a single-phase system [14]. Model predictive control (MPC) are applied for GCI current control systems in [15,16].…”