DOI: 10.5176/ 978-981-07-7531-5_PEEE.19
Authors: Loo Hoe Fieh, V. K. Ramachandaramurthy, Yong Chung Lern and Mohd Shukri Ismail
There is a substantial increase in the number of distributed generators (DG) connected to the distribution network in recent years. The connection of DG will change the fault current and result in reverse power flow in the network. Hence, additional study must be under taken for conditions such as anti-islanding, sympathetic tripping, under or overcurrent and voltage fluctuation. This paper will explore the anti-islanding and overcurrent protection for the PV system with generation capacity of 5, 10, 20, 40 MWpeak (pk) interconnected to the distribution network. An inverse definite minimum time (IDMT) overcurrent protection relay is coordinated for the test distribution network. Besides that, a solar photovoltaic (PV) plant using an anti-islanding detection scheme based on voltage passive detection technique is coordinated. The result obtained shows that IDMT is able to trip selectively according to the phase fault location with grading margin of 0.4s between two different zones. The passive detection technique is shown to able to detect the islanding under different value of load and fault back feed current. The islanding conditions are verified for each solar PV generation capacity.
Keywords: Distribution generators (DG), solar photovoltaic (PV), inverse definite minimum time (IDMT), overcurrent (OC) relay, DigSilent PowerFactory, islanding, network protection