CP automation approached for a solution to harmonic noise
Power quality specialist CP Automation was approached during the upgrading of a biomass power plant to mitigate harmonic noise as part of the tender to prevent it from causing component failure and severe damage to the local power supply.
Harmonic noise causes problems in many industrial facilities which contain non-linear loads. A common source of harmonic distortion power plants include variable speed drives (VSDs) to control transformers and motor speed. VSD is critical for keeping industrial machinery running but can introduce harmonics due to the rapid switch of power electronic components.
John Mitchell, global sales and marketing director at CP Automation said: “The filters actively inject a counter signal to cancel out the harmonic noise returning to the transformer, acting like noise-cancelling headphones. We supplied six of these filters across the site.”
Problems can occur when the total harmonic current distortion (THDI) of the VSDs significantly increases and passes back to the transformer. The transformer may start distorting the waveform being sent out to surrounding electrical equipment if the harmonic loss factor (FHL) curve is breached. This can be caused by a different load sum at the transformer with current distortion exceeding normal levels.
Distorted voltage waveforms will degrade hardware receiving the signal in the power network, damaging the components inside and shortening the device's life expectancy by several years. It can also derate the available power from the transformer.
CP Automation designed a solution for this specific problem, it supplies six Comsys ADF P300 active harmonic filters which helped resolve the THDI of the current caused by VSDs.
A backup system has been set up to ensure essential services continue to work in the event of a mains outage. Two uninterruptible power supply (UPS) units were supplied which can provide almost instantaneous power for critical services such as; fuel handling, conveyor systems, and boiler control units. Remote monitoring can be achieved through using Ixon IoT routers, meaning if an outage or power quality event is detected CP Automation’s team can dial in and provide remote support.
Mitchell added: “Like other power plants and industrial facilities, the installation of harmonic filtration has opened the door for subsequent monitoring capabilities. Analysing options include portable clamps such as multimeters and fixed power quality meters, such as Powerside’s PQube 3 and Janitza’s range of panel mounting and din rail analysers.”
After the installation of the Comsys filter and UPS system, upgrades to the facility could be completed. This boosts uptime whilst also reducing long-term costs by prolonging the lifespan of the electrical equipment on site, protecting them from waveform distortion.
Long-term trends can be tracked by strategically placing power quality meters across the plant. This allows CP Automation to carry out root-cause analysis. Identifying any ongoing issues as well as what the plant looks like at a snapshot can be achieved by conducting a power quality survey.
