RW Energy Kenya 11 kV Ring Main Unit RMU Controller Intelligent Retrofit Case Study

Based on the upgrading demands of aging power distribution equipment in Kenya, we specialize in intelligent RMU retrofitting. Integrating wireless communication and distributed intelligent control technologies, the solution adapts to harsh outdoor operating conditions. Without replacing main equipment, it enables intelligent upgrading of legacy RMUs, delivering fast fault handling and precise grid-connected monitoring. While improving quality and reducing costs, it consolidates the foundation of regional distribution network automation, modernizes outdated power facilities, and enhances power supply stability as well as operational efficiency.

01 Project Overview

1.1 Project Background

As a key economic hub in East Africa, Kenya has experienced rapid urbanization and industrialization in recent years. The large-scale integration of new loads, such as energy storage systems (BESS) and electric vehicle (EV) chargers, has placed higher demands on the reliability and automation level of the power distribution network.

The existing local grid contained a significant number of legacy Ring Main Units (RMUs) that had been in operation for many years. These units suffered from low intelligence levels and had long been operating in "isolation," meaning they were unable to connect to the power monitoring system and lacked telemetry, remote signaling, and remote control (Three-Remote) capabilities. This led to slow fault location, prolonged recovery times, significant voltage fluctuations, high manual inspection costs, and low O&M efficiency, severely hindering the modernization of the distribution network.

To address these pain points, the Kenyan distribution operator introduced the RW Energy RMU Intelligent Retrofit Solution. Leveraging distribution automation, and wireless communication technologies, the project professionally upgraded the RMUs to achieve online monitoring, intelligent O&M, and rapid fault handling, comprehensively enhancing grid safety and stability.

1.2 Core Retrofit Solution and Product Configuration

This project focused on implementing wireless encrypted communication and "Three-Remote" function upgrades for 11 kV RMUs in Kenya. The core configurations are as follows:

02 Technical Design and Quality Assurance

2.1 Core Technical Design

• Seamless Integration: RW Energy utilizes a lightweight integration of equipment combined with a wireless communication access solution, achieving intelligent upgrades without replacing the existing RMU primary switchgear.
• Environmental Adaptation: Designed for Kenya's high temperature, high humidity, and heavy dust environments, the terminal enclosures feature anti-corrosion, dust-proof, and UV-resistant structures suitable for long-term outdoor operation.
• Distributed Intelligence: The system adopts distributed intelligent control algorithms to quickly locate ring network faults, automatically complete fault isolation, and rapidly restore power to non-faulty areas.
• Online Monitoring: The equipment supports real-time monitoring of operating status, collecting data such as current, voltage, switch position, and equipment temperature for upload to the master station platform.

• Protocol Compatibility: Fully supports international mainstream protocols such as DNP3.0 and IEC 60870-5-104, with dual-way encryption to perfectly match the Kenya National Grid master station.

2.2 Quality Certification

• RW Energy has established a comprehensive management system for quality, environment, and occupational health and safety, passing ISO 9001, ISO 14001, and ISO 45001 certifications. All RMU retrofit terminals and communication modules have been tested by international authoritative agencies, complying with IEC standards and Kenyan local technical specifications to ensure stable operation under complex overseas conditions.

2.3 Drawing Design and Delivery

• RW Energy provided a full set of standardized electrical drawings for this project, covering FTU controller electrical principles, system wiring, communication networking, and sampling circuits. All designs strictly follow IEC international standards and Kenyan grid codes. The provided FTU controller electrical schematics clearly present the logic for power supply, sampling, control, communication, and protection, ensuring the precise implementation of the retrofit solution.

DC Type Drawings:

03 Factory Testing

All units underwent rigorous testing in RW Energy laboratories:

• Three-Remote Function Test: Simulated field switch operations, data collection, and remote control. Telemetry accuracy achieved ≤ 0.5 %, with a remote control response time of ≤ 50 ms and 100 % action accuracy.
• Protection Function Test: Simulated over-voltage, under-voltage, over-current, and zero-sequence faults. Protection response time achieved ≤ 50 ms with 100 % accuracy and zero malfunctions.
• Environmental Simulation: Simulated high temperature, high humidity, salt spray, and dust. The equipment operated continuously without abnormality, proving its stability in African field conditions.

04 Packaging and Shipping

• All equipment utilized specialized heavy-duty export packaging (moisture-proof, vibration-proof, and dust-proof). Core electrical components were vacuum-sealed, and enclosures were protected by reinforced wooden crates with internal cushioning. This ensures the equipment remains intact during long-distance maritime and inland transport across Africa. All terminals, cables, and spares were clearly labeled and shipped with full technical dossiers for smooth customs clearance and installation.

05 Installation and Operation Feedback

5.1 Installation Implementation

• RW Energy dispatched professional technical teams to Kenya to provide full-process installation and commissioning services.
• Guided the construction of foundations, earthing systems, and enclosure fixing.
• Completed cable terminations, insulation testing, controller parameter configuration, and master station system integration.

• Conducted comprehensive training for local O&M personnel and delivered full technical dossiers and maintenance manuals.

5.2 Operation Feedback

• System Stability: The retrofitted RMUs operate stably, achieving precise fault location and automatic isolation, which has significantly shortened power outage durations.
• Voltage Quality: Real-time monitoring and optimized load scheduling have effectively supported grid-side voltage regulation, significantly improving end-of-line voltage quality.
• Efficiency Gains: The O&M model has been upgraded from manual inspection to remote online monitoring, greatly increasing efficiency and reducing costs.
• Future-Proofing: Legacy RMUs are now successfully integrated into the distribution automation platform, enabling unified scheduling and laying the foundation for future renewable energy integration.
• Renewable Energy Control: The addition of remote control functions enables the emergency disconnection and grid-tied control of distributed energy resources (DERs), solving the safety risks of reverse power flow.

The project received high recognition from the Kenyan distribution operator and energy authorities, who stated: "The RW Energy RMU intelligent retrofit solution efficiently revitalizes legacy equipment and rapidly improves distribution automation levels with reliable technology and professional service."

06 Full Lifecycle O&M Managed Services

RW Energy provides integrated full-lifecycle O&M managed services for the Kenya RMU controller upgrade project. This covers pole-mounted circuit breakers, Ring Main Units (RMUs), distribution automation terminals (FTU/DTU), communication gateways, monitoring systems, and associated equipment such as BESS, EV chargers, and capacitor banks.

Our services include selection adaptation, commissioning, online monitoring, regular maintenance, parameter optimization, 24/7 fault repair, and personnel training. Through dedicated personnel and closed-loop management, we ensure the long-term stable operation of retrofitted equipment, extend service life, and reduce costs for the Kenyan power grid and its evolving load requirements.

Contact us to upgrade your old equipment with RW Energy controllers and join the future of smart grids!