4165 (RP-770) -- The Effect of Distribution System Parameters on Air-Conditioning Motor Start-up Flicker PDF

This study was undertaken to analyze the parameters involved in "flicker" associated with air-conditioning and heat pump motor starts. This study may be unique in its use of both modeling and actual field data to examine start-up flicker from a utility perspective. Flicker is the term used to describe the brief voltage drop that occurs due to the combination of system impedances and the high current required by the compressor motor to start. This paper looks at the magnitude of the voltage sag and what a power utility can do to minimize flicker complaints. A simplified model of a residential distribution system is evaluated with various types of conductors and transformers. Field data taken from a scroll-type air-conditioning unit are then used to examine the effects of changing various parameters in the residential distribution system. Using the field data and the model of the distribution system, several system parameters are varied to determine their impact on the voltage sag experienced by the residential customer. The addition of a capacitor hard start kit was found to be effective in reducing the duration of the start period, thus reducing customer complaints.

Units: I-P