The effects of major solar integration on a 21-Bus system: Technology review and PSAT simulations

The world's energy needs are changing and so are the methods by which it generates power. Photovoltaic Cells are leading this revolution by harnessing the power of the sun and transforming it into DC power. Integrating this “too good to be true” power source into the grid has been in the mind of those who plan for future grid alterations for a while and the need for seamless integration has arrived. Power systems and power-flow through the grid are planned precisely and do not respond well to sudden changes. Large-scale PV grid integration is challenging and requires preparation to deal with the intermittency of power production. This paper analyzes an IEEE 21-Bus power system with regards to power-flow and small to large scale integration of PV generation. The pros and cons of this addition are researched and documented here as well as simulations of PV integration using Matlab's Power System Analysis Toolbox (PSAT) software. There are a few correction methods that attempt to solve some of the known problems with adding solar generation into the grid such as tap-changer transformers, capacitor banks, and synchronous condensers. Besides normal analysis, this paper also presents one of these correction methods into simulation to show how part of the large-scale integration problem can be corrected.