JWG C4/C6.29 Power Quality Aspects of Solar Power


There has recently been a huge increase in the amount of solar power connected to the grid and this trend is expected to continue and even grow during the coming years.

A possible concern with the connection of solar-power installations is their potential impact on the voltage and current quality in the grid. The principle aim of this working group is a mapping and quantification of that impact where it concerns power quality disturbances. A decision about possible negative impacts can only be made, most likely on a case by case basis, after the completion of the working-group activities.

The following power-quality disturbances will be covered by this working group:

  • Characteristic harmonics (odd harmonics up to 2 kHz for single-phase installations; odd non-triple harmonics for three-phase installations).
  • Low-order non-characteristic harmonics (even harmonics and interharmonics up to 2 kHz, also odd triple harmonics for three-phase installations)
  • High-frequency distortion (frequency-components in the frequency range 2 to 150 kHz)
  • Single rapid voltage changes, flicker and other voltage-magnitude variations at time scales below 10 minutes.
  • Unbalance due to single-phase installations
  • Supply voltage variations at time scales of 10 minutes and longer

For supply voltage variations at time scales of 10 minutes and longer, already well documented from work done elsewhere, a brief description of the basics and of the state-of-the-art will be given.

For each of the other listed disturbances, the emission by solar-power installations will be mapped based on detailed measurements. As much as possible measurements from actual installations will be used. Information from relevant literature will be used as well.

The impact on voltage quality will be studied where this differs from the impact of emission by other equipment. This part of the work will cover a combination of measurements, simulation studies and information from relevant literature.

For low-order non-characteristic harmonics, high-frequency distortion and other voltage-magnitude variations at time scales below 10 minutes, proposals for appropriate compatibility levels, voltage characteristics, and emission limits will be given.

Power frequency variations, overloading and increased losses due to reverse power flow, voltage dips, voltage transients, and other impacts or disturbances not mentioned above, are beyond the scope of this working group.

Deliverables :
  1. A CIGRE report containing the results from the studies mentioned above.
  2. Electra publication summarising major conclusions and recommendations and technical papers reporting intermediate results
Convener: J. Smith (USA)

Progress Report 2013 (pdf, 79kB)

Progress Report 2014 (pptx, 100kB)

Progress Report 2015 (pptx, 101kB)