79 Proceedings International Conference on Science and Technology (ICST) e-ISSN: 2722-7375 pp: 79-87, Vol. 1, Juni 2020 Performance Improvement of Grid Tie Inverter on Microgrid of Solar Photovoltaic Abdul Natsir, Supriyatna, Ni Made Seniari, Ida Ayu Sri Adnyani, Sabar Nababan University of Mataram, Jl. Majapahit 62, Mataram, Indonesia Email: natsir.amin@unram.ac.id, supriyatna@unram.ac.id, seniari70@unram.ac.id, adnyani@unram.ac.id, nababan.sabar@gmail.com. Abstract. Microgrid systems are supplied from solar photovoltaic (PV) as an input grid-tie inverter (GTI). In this research, GTI used is a grid-tie micro-inverter 1000 watt. GTI is a power converter direct current (DC) into alternating current (AC) and can operate when connected to electricity grid utility. GTI output connected to a local load such as incandescent lamps, CFL lamps, small refrigerators, TV and fans. The problem with the microgrid system with GTI is GTI unable to operate to generate power if it does not detect the reference voltage of grid utility (islanding condition). This research proposes the idea to replace electricity grid utility with a battery system from wind power generation when grid utility is interrupted or blackout. The research experiment conducted in a renewable energy laboratory of Faculty of Engineering, University of Mataram. The addition of controlled renewable energy sources such as small wind turbines can improve the performance of GTI to optimize power generated on the microgrid system, when electricity from power grid utility is interrupted or outages. The variables measured in GTI performance testing on the microgrid system are voltage, current, and THD. The value of voltage generated by GTI to 2 conditions of test carried out is still within the allowable standard limit of ± 10% of nominal voltage (220 Volts). Similarly, the THD value of the result is still below the specified standard (5%). Keywords: Microgrid, grid tie inverter, renewable energy, solar photovoltaic, small wind turbines 1. Introduction Indonesia has enormous solar energy potential; it is on the equator with global irradiance range 4.20 - 5.27 kWh/m 2 .day [1]. This research is in accordance with Government Regulation No. 79/2014 on National Energy Policy that supports the utilization of solar PV technology as a sustainable energy source for electrical energy needs in Indonesia. With good control systems, microgrid of solar PV can be used as a reliable power generation. The power generated by solar PV varies depending on the solar irradiance received at that time. This causes problems with power quality produced if connected to power grid utility, where solar PV will