This gave rise to regional power grids to be followed by the national power grid and the international power grid . The integration of power generation and transmission over vast distances surely improved reliability, decreased the price of electricity, and served larger population. However this came at a price - power quality . When large-scale power grids were built, electrical equipment at that time did not seriously get affected by power quality as the modern electronic equipment does today. Over years the widespread use of solid-state electronics, integrated electronics equipment, and digital electronics, has placed unprecedented requirements on power systems.
Power quality is increasingly an issue.
Developments in solid-state power electronics have allowed immense progress to be made in the use of electronic equipment. This equipment ranges from computers, microwave ovens to variable frequency drives and power inverters used with diverse power sources such as solar photo voltaic and wind generators. The generally accepted use of the term power quality does not include reliability of power system. This article provides the introductory information on power quality and reliability. It also discusses the most recently used Power Industry Model and the Deregulation of power industry.