Pendulum Power Consultants
Pendulum Power Group

Case studies

From Challenge to Solution

Harmonic Load Flow Analysis for Factory Expansion

Client Background & Needs

A manufacturing facility undergoing expansion required an additional arc furnace as part of a major site upgrade. The site was already experiencing elevated harmonic levels due to ageing arc furnaces, yet no G5/4 assessment had previously been conducted.

To accommodate the new arc furnace, the factory required an upgraded 11kV supply. However, the DNO would not energise the new supply until it could be proven that the site was compliant with G5/4 harmonic limits at the point of connection.

Our expertise in harmonic analysis and power system modelling made us the ideal partner for the project.

 

Challenges & Approach

Several challenges arose during the project:

  • Harmonic Issues: The existing site’s elevated harmonic levels presented a risk of non-compliance.
  • On-Site Data Collection: Accurate data was essential to model the site’s electrical network.
  • Environmental Factors: The site was operational throughout the analysis, requiring minimal disruption to daily activities.

Our approach involved conducting an on-site G5 analysis over a one-week period to gather essential data. Using an advanced analyser capable of measuring up to the 50th harmonic, we collected information on:

  • The characteristics of the new supply transformer
  • The harmonic profile of the new arc furnaces
  • Cable sizes and lengths
  • Background harmonic levels and network fault levels provided by the DNO

This data was vital for building an accurate model of the electrical network.

 

Implementation & Solution

The collected data was input into our detailed power system model, where we calculated the harmonic components at 11kV. The analysis confirmed that the site was:

  • Not compliant with G5/4 in its current state
  • Unable to meet G5/4 compliance following the installation of the additional arc furnace

To address this, we designed a bespoke active harmonic filtration system. Working closely with our power quality partners, we ensured the solution was tailored to the site’s load profile and harmonic characteristics. The filtration system was installed, tested, and commissioned to ensure full compliance.

 

Results & Impact

  • The new 11kV supply was successfully energised after demonstrating compliance with G5/4 standards.
  • The factory could proceed with its expansion plans without delays.
  • The installation improved the site’s power quality, reducing the risk of equipment malfunctions and enhancing system reliability.

Our solution provided a long-term strategy for managing harmonic distortion as the site’s load continues to grow.

 

Conclusion & Key Takeaways

This project showcased our ability to manage complex power quality challenges through a combination of detailed analysis, effective design, and collaborative working. By implementing a tailored filtration system, we ensured regulatory compliance while improving system performance.

Our expertise in harmonic analysis, G5/4 assessments, and active filtration solutions demonstrates our commitment to delivering solutions that protect both client infrastructure and the wider power network.

 

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Pendulum Power Group

Modern Slavery & Human Trafficking Statement

PPC Ltd is committed to preventing modern slavery and human trafficking in all areas of our business and supply chain. We operate solely within the UK, providing consultancy and technical services to the energy and power sector. Our supply chain includes specialist subcontractors, UK-based service providers and technical equipment suppliers.

We have a zero-tolerance approach to modern slavery and uphold this through:

 

Our Policies & Responsibilities

  • A formal Modern Slavery and Human Trafficking Policy (HR-010)
  • Clear responsibilities for Directors and senior management
  • Annual policy review and company-wide communication
  • Integration with our ISO-aligned management systems

 

Supplier Due Diligence

We assess and monitor suppliers through our approval process, including checks on controls relating to modern slavery. Higher-risk suppliers—such as those outside the UK/EU—are subject to enhanced scrutiny. We will not work with any organisation involved in slavery or trafficking.

 

Training & Awareness

Employees receive induction awareness, access to our modern slavery policy, and ongoing updates. Additional training is provided for those involved in procurement and supplier management.

 

Risk Management

We monitor risks in our supply chain and found no evidence of modern slavery during this reporting period. We continue to improve our assessment processes and supply chain visibility.

 

Reporting Concerns

Employees can report concerns through management or our formal reporting procedures. All reports are investigated, and breaches follow disciplinary actions as defined in HR-010.

 

Continuous Improvement

In 2025 we will strengthen supplier assessments, expand training, and ensure this statement remains up to date and transparent.

This statement has been approved by the Director and is published in accordance with the Modern Slavery Act 2015.