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MAJOR FACTORS CONTRIBUTING TO POWER QUALITY ISSUES

The three major factors contributing to the problems associated with power quality are:

USE OF SENSITIVE ELECTRONIC LOADS

The electric utility system is designed to provide reliable, efficient, bulk power that is suitable for the very large majority of electrical equipment. However, devices like computers and digital controllers have been widely adopted by electrical end-users. Some of these devices can be susceptible to power line disturbances or interactions with other nearby equipment.

THE PROXIMITY OF DISTURBANCE-PRODUCING EQUIPMENT

Higher power loads that produce disturbances – equipment using solid state switching semiconductors, arc furnaces, welders and electric variable speed drives – may cause local power quality problems for sensitive loads.

SOURCE OF SUPPLY

Increasing energy costs, price volatility and electricity related reliability issues are expected to continue for the foreseeable future. Businesses, institutions and consumers are becoming more demanding and expect a more reliable and robust electrical supply, particularly with the installation of diverse electrical devices. Compatibility issues may become more complex as new energy sources and programs, which may be sources of power quality problems, become part of the supply solution. These include distributed generation, renewable energy solutions, and demand response programs Utilities are regulated and responsible for the delivery of energy to the service entrance, i.e., the utility meter. The supply must be within published and approved tolerances as approved by the regulator. Power quality issues on the “customer side of the meter” are the responsibility of the customer. It is important therefore, to understand the source of power quality problems, and then address viable solutions.

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