Investigations on the impact of voltage and current harmonics on end-use devices and their protection: Summary report for period January 1, 1980-June 30, 1986

Technical Report · Sun Jan 01 04:00:00 EST 1967

DOI:https://doi.org/10.2172/6683865· OSTI ID:6683865

Fuchs, E. F. ^[1]

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1. Univ. of Colorado, Boulder, CO (United States)

After defining the relation between harmonic voltages and currents through harmonic impedances, the impact of harmonics on electromagnetic end-use devices such as transformers and machines is formulated based on analytical and experimental investigations. A harmonic factor representing the square of a weighted total harmonic distortion factor provides a mechanism for estimating the reduction of lifetime of electromagnetic end-use devices due to additional losses generated by sets of harmonics of frequencies below 2000 Hz. The forces and torques of saturable three-phase induction machines during starting and steady-state operation are computed from magnetic field solutions. Within the above frequency range the accuracy of induction watthour meters is reduced and the impact of harmonics or fractional harmonics (which exhibit a frequency other than those of harmonics and subharmonics) on distribution system relays can be severe. Also, the performance of television sets deteriorates for fractional harmonics below 2000Hz. The impact of harmonics on shunt capacitors limits the harmonic amplitudes with frequencies above 2000Hz. Depending upon the size of the system impedance either the harmonic voltages or the harmonic currents will be predominant. For small impedances the values of the harmonic currents will be limited by the permissible harmonic current loading of pole and substation transformers, whereas for large impedances the harmonic voltage amplitudes will be limited by the permissible additional losses in parallel connected electromagnetic end-use devices. The propagation of harmonics within a distribution feeder is such that for dispersed harmonic sources of the same kind no significant canceling of harmonic amplitudes occurs. Under certain circumstances the propagation of harmonics within a distribution feeder can cause resonances.

• Research Organization: Univ. of Colorado, Boulder, CO (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC02-80RA50150
• OSTI ID: 6683865
• Report Number(s): DOE/RA/50150--23; ON: DE87008018
• Country of Publication: United States
• Language: English

Related Subjects

200300* -- Electric Power Engineering-- Power Transmission & Distribution-- (-1989)
24 POWER TRANSMISSION AND DISTRIBUTION
CAPACITORS
ELECTRIC MEASURING INSTRUMENTS
ELECTRIC MOTORS
ELECTRICAL EQUIPMENT
EQUIPMENT
HARMONICS
MEASURING INSTRUMENTS
METERS
MOTORS
OSCILLATIONS
POWER DISTRIBUTION SYSTEMS
POWER METERS
RELAYS
TELEVISION