An important part of power quality is steady-state (and quasi-steady-state) waveform distortion. The resulting information is sometimes presented in the time-domain (e.g. notching) and more often in the frequency-domain (e.g. harmonics and interharmonics). Randomly varying non-linear loads, such as arc furnaces, as well as substantial and varying harmonic (and interharmonic) content, cause voltage fluctuations that often produce flicker. The random nature of the load impedance variation with time prevents an accurate prediction of the phenomena. However, the EMTP method can still help in the selection of compensating techniques, with arc models based on the experience of existing installations. Another application of the EMTP method for steady-state assessment is its use in developing accurate harmonically coupled models for other modelling frame-works, such as the harmonic domain. This is desirable as frequency-domain techniques are more amendable for simulating very large power systems.

Chapter Contents:

• 11.1 Introduction
• 11.1 Introduction
• 11.2 Phase-dependent impedance of non-linear device
• 11.2 Phase-dependent impedance of non-linear device
• 11.3 The time-domain in an ancillary capacity
• 11.3 The time-domain in an ancillary capacity
• 11.3.1 Iterative solution for time invariant non-linear components
• 11.3.1 Iterative solution for time invariant non-linear components
• 11.3.2 Iterative solution for general non-linear components
• 11.3.2 Iterative solution for general non-linear components
• 11.3.3 Acceleration techniques
• 11.3.3 Acceleration techniques
• 11.4 The time-domain in the primary role
• 11.4 The time-domain in the primary role
• 11.4.1 Harmonic assessment historically
• 11.4.1 Harmonic assessment historically
• 11.4.2 Basic time-domain algorithm
• 11.4.2 Basic time-domain algorithm
• 11.4.3 Time-step
• 11.4.3 Time-step
• 11.4.4 dc System representation
• 11.4.4 dc System representation
• 11.4.5 ac System representation
• 11.4.5 ac System representation
• 11.5 Discussion
• 11.5 Discussion
• References
• References

Inspec keywords: power system transients; time-domain analysis; power system simulation; power supply quality; frequency-domain analysis; radiofrequency interference

Other keywords: steady-state waveform distortion; voltage fluctuations; nonlinear loads; very large power systems; harmonically coupled models; power quality; harmonic content; frequency-domain; arc furnaces; flicker; time-domain; harmonic domain

Subjects: Electromagnetic compatibility and interference; Power supply quality and harmonics; Power systems; Mathematical analysis