Power quality performance component of the special manufacturing contracts between power provider and customer

In 1995 Detroit Edison entered into long-term pricing and service quality agreements with Chrysler Corporation, Ford Motor Company, and General Motors Corporation. The terms are specified in an agreement known as the Special Manufacturing Contract (SMC). The service agreement covers voltage interruptions and voltage sags. Detroit Edison became liable for interruptions that exceeded performance targets effective January 1995. The voltage sag amendment to the SMC, effective January 1998, makes Detroit Edison liable to the customers if voltage sag measures exceed performance targets. Detroit Edison has installed a power quality monitoring system at 56 of the three customers´ locations throughout its territory. The power quality monitoring system allows Detroit Edison to determine the frequency and severity of voltage sags that occur at the customer locations. This paper presents the purpose and rules of the voltage sag agreements. It explains the definition of a sag score. The sag agreements define what is a qualifying sag and what is a nonqualifying sag. Example computations of sag scores are furnished