Power Factor Correction Rebuild with Detuning Reactors in Central London
Power quality issues are becoming increasingly common in modern commercial and industrial installations, particularly in dense urban environments where harmonic distortion can significantly impact electrical performance. We were recently tasked with rebuilding a power factor correction (PFC) system at a site in Central London, addressing both component failure and rising harmonic levels.
The Challenge
The existing PFC unit had suffered multiple failures, with all three 50kVAr stages no longer operational. In addition, the site was experiencing a voltage total harmonic distortion (VTHD) level of 4% and rising, indicating increasing harmonic stress on the system.
Attempting to restore the system using standard capacitor banks alone would have risked amplifying harmonic issues further—a common problem in installations with non-linear loads.
The key objectives were:
- Restore reliable power factor correction
- Prevent further harmonic amplification
- Improve overall system stability and performance
The Solution
To address both the failed equipment and the harmonic concerns, we carried out a full rebuild of the PFC system incorporating detuning reactors.
Key Elements of the Upgrade:
- Detuning Reactors Installed
These were integrated to prevent resonance and suppress the impact of harmonics, ensuring the new system would not contribute to rising distortion levels. - Reconfigured Capacitor Stages
Two new PN54 capacitor trays were installed, split into 25kVAr and 50kVAr stages. This provided more flexible step control and improved responsiveness to varying load conditions. - Lovato DCRL8 Controller
A new, advanced controller was fitted to provide accurate power factor regulation and improved monitoring of system performance. - New Control Wiring & Power Cabling
All associated wiring was upgraded as part of the rebuild, ensuring long-term reliability and compliance with current standards.
Installation & Commissioning
The project was completed by a two-engineer team in just one day, with careful planning ensuring no disruption to site operations.
Following installation and commissioning, the system delivered immediate results:
- Power factor improved from 0.9 to unity (1.0)
- No increase in harmonic distortion levels, despite restoring full PFC functionality
This demonstrated the effectiveness of the detuned design in maintaining power quality while achieving optimal correction.
Environmental Responsibility
All redundant equipment was removed from site and disposed of responsibly, in line with current environmental and waste management regulations.
The Outcome
The upgraded system now provides:
- Stable, reliable power factor correction
- Protection against harmonic-related issues
- Improved efficiency without compromising power quality
- Greater flexibility in load management
Conclusion
As harmonic distortion becomes more prevalent in modern electrical systems, integrating detuning reactors into PFC installations is no longer optional—it’s essential. This project highlights how the right design approach can resolve existing issues while future-proofing the installation.
