Low voltage ride through capability of a 5 kW grid-tied solar inverter

Abstract

Distributed power generation systems (DPGS) such as wind and solar become more and more widely spread. As a consequence grid operating companies demand system services. As part of the general fault ride through (FRT) requirements this paper deals with low voltage ride through (LVRT) capability of a three-phase-four-wire gridtied solar inverter. The standard system will be described and necessary changes to the control such as positive (PS), negative (NS) and zero sequence (ZS) separation, a stable phase-locked-loop (PLL) as well as voltage support by means of reactive current as well as stress factors to the hardware will be identified.

Overview of Single-phase Grid-connected Photovoltaic Systems

“…In the case of large-scale PV systems with higher power ratings, the PV systems should not violate the grid voltage and the grid frequency by means of providing ancillary services (e.g., frequency regulation). Additionally, the PV systems have to ride-through grid faults (e.g., voltage sags and frequency changes), when a higher PV penetration level comes into reality [18], [21], [27]- [33].…”

“…Nevertheless, different methods to extract the grid voltage information have been developed in recent studies [26], [68], [79]- [82] like the zero-crossing method, the filtering of grid voltage method, and the Phase Locked Loop (PLL) techniques, which are the promising solutions. In addition to the phase of the grid voltage, other grid condition information is also very important for the control system to perform special functionalities, e.g., low voltage ride through [27], [32], where the grid voltage amplitude has to be monitored. Thus, advancing the monitoring technology is another key to a grid-friendly integration of grid-connected PV systems.…”

Smart Grid and its future perspectives in Australia

“…Generally, the impacts of PV variability on the distribution system can be managed with advanced controls. Nowadays, the most grid-tie inverters are designed based on UL 1741 which is harmonized with IEEE 1547 [38]. These inverters are actively participating in grid functions like voltage regulation to maintain reasonable voltage levels.…”

A review of low voltage ride-through techniques for photovoltaic generation systems

“…Obviously, orthogonal algorithms, such as T/4 delay method [14], differentiation method [12] and Second-Order-GeneralizedIntegrator (SOGI) method [15], are essential and key techniques to realize the sequence separation. Fig.…”