Harmonic Analysis Study for a 110/13.8 kV High-Voltage Substation
Power quality becomes increasingly important as electrical networks become more complex and harmonic-producing equipment and filtering systems are integrated into high-voltage infrastructure.
To support reliable network operation, Power Projects has been awarded a comprehensive Harmonic Analysis Study for a 110/13.8 kV high-voltage substation.
The study will assess harmonic performance across the network, evaluate the effectiveness of installed harmonic filter capacitor banks, identify potential resonance conditions and verify compliance with applicable utility power quality requirements.
The study will be performed using DIgSILENT PowerFactory and is scheduled for completion within 3 weeks following receipt of the purchase order and complete input data.
Project Overview
The project involves a 110/13.8 kV high-voltage substation incorporating a 13.8 kV distribution network and three 7 MVAr filter capacitor banks.
The installed filters are:
- Three 7 MVAr filter capacitor banks
- Double-star connected band-pass harmonic filters
- Ungrounded neutral
The objective of the study is to assess voltage and current harmonic distortion throughout the network, evaluate harmonic filter performance and identify network resonance characteristics that could affect system performance and long-term operation.
The study will also verify compliance with the applicable utility power quality requirements.
What Does the Harmonic Analysis Study Cover?
The engineering assessment brings together several key aspects of network harmonic performance.
Harmonic Load Flow Analysis
The Harmonic Load Flow Study will assess the network harmonic behaviour up to the 100th harmonic order.
The assessment includes:
- Total Harmonic Distortion (THD)
- Individual harmonic distortion
- Voltage harmonic profiles
- Current harmonic profiles
- Harmonic performance under normal operating conditions
This provides an overall picture of the harmonic distortion present throughout the electrical network.
Frequency Scan and Resonance Assessment
Harmonic distortion cannot be assessed independently of the network's frequency-dependent characteristics.
The frequency scan will evaluate:
- Parallel resonance conditions
- Series resonance conditions
- Network harmonic impedance characteristics
- System response after installation of harmonic filters
The assessment will help identify resonance frequencies that could amplify harmonic distortion or adversely affect electrical equipment.
Evaluating the Installed Harmonic Filters
The project includes assessment of the installed three 7 MVAr filter capacitor banks.
The filter performance evaluation will consider:
- Harmonic attenuation capability
- Filter tuning effectiveness
- Reactive power contribution
- Compliance with applicable harmonic limits
The simulation results will be used to provide engineering recommendations for improving harmonic mitigation, where necessary.
This makes the assessment more than simply a harmonic distortion check — it also provides an evaluation of how the installed filtering system performs within the network.
Technical Methodology
The study will be developed in DIgSILENT PowerFactory, with the network model representing the electrical characteristics of the complete substation.
1Input Review and Network Model Development
The study begins with:
- Review of the single-line diagram
- Development of a detailed DIgSILENT network model
- Validation of transformer and network parameters
- Modelling of harmonic filter capacitor banks
- Verification of system operating configuration
2Harmonic Load Flow
The network will then be assessed up to the 100th harmonic order, including voltage and current harmonic distortion and individual harmonic components.
3Frequency Scan
The frequency-dependent network response will be evaluated to identify series and parallel resonance conditions and assess network harmonic impedance characteristics.
4Filter Performance Assessment
The installed filter capacitor banks will be evaluated for harmonic attenuation, tuning effectiveness, reactive power contribution and compliance with applicable harmonic limits.
5Engineering Recommendations
Where required, recommendations will be developed based on the simulation results to improve harmonic mitigation.
Why Harmonic Studies Matter for High-Voltage Substations
Harmonic performance is an important part of maintaining reliable power quality in high-voltage electrical networks.
Without a comprehensive harmonic assessment:
- Harmonic distortion may exceed acceptable limits
- Resonance conditions may remain undetected
- Harmonic filters may not perform as intended
- Equipment life and network reliability may be affected
A detailed assessment helps identify these conditions through simulation before they become operational concerns.
Through this project, Power Projects supports:
- Improved power quality performance
- Effective harmonic mitigation
- Validation of harmonic filter performance
- Identification of resonance risks
- Compliance with utility harmonic requirements
- Reliable long-term operation of high-voltage substations
Delivering the Study Within 3 Weeks
Despite the detailed network modelling, harmonic simulations, resonance assessment and filter performance evaluation involved, the complete Harmonic Analysis Study will be delivered within a 3-week schedule, following receipt of the purchase order and complete input data.
This reflects Power Projects' focus on combining detailed engineering analysis with efficient project delivery.
Power Quality Engineering for High-Voltage Networks
This project further strengthens Power Projects' expertise in power quality engineering and harmonic studies for utility substations and transmission infrastructure.
Our engineering team provides specialised services covering Harmonic Analysis, Power Quality Studies, Grid Compliance, Protection Engineering and Electromagnetic Transient Studies.
Power Projects supports utilities, transmission operators, EPC contractors and renewable energy developers using advanced engineering software including:
Looking for Harmonic Analysis Support?
Whether the requirement involves harmonic distortion assessment, frequency scan and resonance evaluation, harmonic filter performance assessment or broader power quality studies, detailed network analysis can help identify potential issues and support reliable electrical system operation. Power Projects is ready to support your next power system study.