Harmonic Distortion
What is Harmonic Distortion?
Harmonic distortion in the power grid refers to deviations from the ideal sinusoidal waveform of voltage or current, typically caused by non-linear electrical loads. These include:
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Frequency converters
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Switch-mode power supplies
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Charging infrastructure (e.g., EV chargers)
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Battery and inverter-based systems (such as BESS)
Such equipment introduces harmonic currents into the grid, generating voltage harmonics due to the grid’s impedance. These harmonics are integer multiples of the fundamental 50 Hz frequency and can result in:
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Overheating or premature aging of electrical components
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Malfunction of sensitive electronic devices
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Mechanical vibrations and noise in motors and transformers
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Nuisance tripping of protection devices
Power Quality Standards
To ensure system reliability and stability, grid operators and regulatory authorities define strict requirements for power quality, including:
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Frequency stability: In isolated systems, frequency must remain between 49 Hz and 51 Hz.
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Voltage variation: Voltage at the point of common coupling (PCC) in low-voltage networks must stay within ±10% of the nominal value.
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Total Harmonic Distortion (THD) must not exceed 8% over a 10-minute average for households and small businesses, and 5% over a one-week average. Stricter limits apply at higher voltage levels.
Our Expertise
We have experience with power quality management, particularly in the integration of BESS in sensitive grid environments. One key example is our delivery of BESS systems to Powerhouse Brattørkaia in Trondheim – one of the world’s most energy-efficient buildings. The project involved stringent requirements for minimal harmonic impact, including:
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Harmonic spectrum measurements and reporting
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Inverter control optimization to minimize emission
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Design and implementation of filtering and mitigation solutions
How We Can Assist
As a certified electrical installer with in-depth EMC and power quality expertise, we can support your project with:
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Power quality audits
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Harmonic analysis and compliance reporting
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Tailored filtering solutions for harmonic mitigation
If your facility is experiencing power quality issues or needs to comply with strict THD limits, we’re ready to help.
Harmonic Distortion in the Power Grid – And How We Can Help
Get in touch
Contact us to discuss how we can ensure harmonic compliance and optimal system performance in your installation.
