Power Projects Awarded Power Factor Improvement and Reactive Power Compensation Study for Thermal Power Plant Auxiliary System

Power Projects has been awarded a Power Factor Improvement and Reactive Power Compensation Study for the auxiliary electrical system of a thermal power plant.

The study focuses on improving reactive power management during operating conditions where the plant auxiliary system is supplied from the grid, including shutdown, startup, maintenance and low-load operating scenarios.

During these conditions, auxiliary loads can experience significant variations in reactive power demand. Effective reactive power compensation is essential to maintain acceptable power factor performance, minimise utility penalty exposure and support stable voltage operation.

Using ETAP simulation software, Power Projects will assess the existing electrical system, evaluate capacitor bank adequacy, review Automatic Power Factor Controller (APFC) performance and develop recommendations for optimised reactive power compensation.

Project Overview

Thermal power plant auxiliary systems consist of multiple electrical loads required for plant operation, maintenance and supporting services. Depending on the operating condition of the plant, the auxiliary demand can vary significantly.

A capacitor bank configuration that performs effectively during one operating condition may not provide optimal performance during another. Inadequate compensation may result in:

• Poor power factor at the grid import point
• Increased utility power factor penalties
• Inefficient capacitor bank utilisation
• Leading power factor conditions during low-load operation
• Voltage rise concerns due to excessive reactive power injection

The objective of this study is to evaluate the existing reactive power compensation arrangement and identify opportunities to improve power factor performance across different auxiliary system operating scenarios.

Electrical System Assessment

The study covers the complete auxiliary electrical distribution system, including:

• 235 kV grid connection
• Generator transformer
• Unit auxiliary transformers
• 6.6 kV auxiliary distribution system
• LV auxiliary network
• Existing capacitor bank installation

The assessment will consider different operating conditions where auxiliary loads are supplied from the grid, including:

• Plant shutdown
• Plant startup
• Maintenance operation
• Low-load operation

Technical Scope and ETAP-Based Study Approach

Power Projects will perform the study using ETAP, developing a detailed electrical model of the auxiliary system and evaluating reactive power behaviour under various operating scenarios.

ETAP Model Development and Input Validation

The study will begin with:

• Review of available electrical system data
• Development of the ETAP model representing the auxiliary network
• Validation of transformer, generator and auxiliary system parameters
• Modelling of existing capacitor banks and APFC operation
• Verification of system operating configurations

A validated simulation model will provide the foundation for evaluating reactive power performance and identifying optimisation opportunities.

Load Flow Analysis and Power Factor Assessment

Load Flow Analysis will be performed to evaluate system performance under different operating conditions.

The assessment will include:

• Voltage profile across the auxiliary electrical network
• Active and reactive power flow distribution
• Power factor at the grid import point
• Transformer loading conditions
• Auxiliary load demand during shutdown, startup, maintenance and low-load operation

The analysis will identify operating scenarios where reactive power demand contributes to reduced power factor performance.

Reactive Power Compensation and Capacitor Bank Optimisation

The study will assess the existing capacitor bank arrangement and determine the most effective compensation strategy for varying auxiliary load conditions.

The assessment will include:

• Capacitor bank adequacy evaluation
• Review of capacitor switching combinations
• Optimisation of capacitor staging
• Reactive power requirement assessment for different operating scenarios
• Evaluation of optimum capacitor step size
• Verification of compensation performance

The objective is to establish a capacitor switching strategy that maintains the required power factor while avoiding overcompensation and leading power factor operation.

APFC Performance Review and Engineering Recommendations

Automatic Power Factor Controller (APFC) operation will be reviewed to evaluate its suitability for the auxiliary system operating conditions.

The review will consider:

• Existing APFC operating philosophy
• Capacitor stage suitability during minimum auxiliary loading
• Voltage rise during capacitor switching
• Risk of overcompensation
• Reactive power injection during low-load operation

Based on the simulation results, Power Projects will provide engineering recommendations covering:

• APFC settings
• Capacitor staging philosophy
• Reactive power compensation requirements
• System operating improvements

Delivering Improved Auxiliary System Efficiency

Reactive power optimisation plays an important role in improving the efficiency and reliability of thermal power plant auxiliary systems.

Through this study, Power Projects will support the client in achieving:

• Improved power factor performance
• Optimised capacitor bank utilisation
• Reduced exposure to utility power factor penalties
• Improved voltage regulation
• Enhanced APFC operation
• Reliable auxiliary power system performance

Project Delivery

The complete study will be delivered within a 2-week schedule following receipt of the purchase order and complete technical input data.

The study combines practical power system engineering experience with advanced simulation capability to provide actionable recommendations for improving reactive power performance.

About Power Projects

Established in 2006, Power Projects provides specialised electrical engineering consultancy services covering:

• Load Flow Studies
• Reactive Power Compensation Studies
• Grid Compliance Studies
• Protection Engineering
• Power Quality Analysis
• Arc Flash Studies
• Renewable Energy Integration Studies

The company supports utilities, industrial facilities and power generation companies using advanced engineering platforms including:

• ETAP
• PSCAD
• PSS®E
• DIgSILENT PowerFactory