Successful Case of 11kV High Voltage Filtering and Compensation Project for Jiangxi Copper Zambia

The Zambia Copper Mine Power Quality Project has been successfully delivered. Post-commissioning, grid stability has improved significantly with zero core equipment downtime, setting a benchmark for power quality governance in African mining.

01 Project Overview

1.1 Project Background

As an important copper resource development enterprise in Africa, Jiangxi Copper Zambia has long been facing power quality challenges caused by high-power heavy-duty equipment.

Core production equipment, such as crushers, ball mills, and belt conveyors, injects a large number of 5th, 7th, and 11th characteristic harmonics into the power grid. This occurs during start-stop operations and operation under variable working conditions.

Consequently, the power grid suffers from a persistently high bus voltage distortion rate and a long-term low power factor.

This issue leads to several negative impacts:

• It significantly increases reactive power loss in lines and transformers.
• It frequently causes maloperation of relay protection.
• It results in precision instrument failures and even local production interruptions.

Ultimately, these problems seriously affect the mine's continuous operation efficiency and equipment service life.

To solve this pain point and implement the development goal of "Green Production, Efficient Power Supply", Jiangxi Copper Zambia has launched a power distribution network upgrade and retrofit project in 2024. The project introduces the RW Energy 11kV Filtering and Compensation Device.

Custom-developed based on the mine's actual load characteristics, this solution accurately filters characteristic harmonics and dynamically tracks the power grid's reactive power demand. It achieves three core benefits for the power grid:

• Precise harmonic mitigation to eliminate characteristic harmonic interference
• Effective grid voltage stabilization to reduce voltage fluctuation risks
• Optimal energy conservation and consumption reduction by improving power factor

The solution provides solid power support for the mine's stable and increased production, as well as long-cycle reliable equipment operation.

1.2 Technical Parameters

02 Product Manufacturing and Assembly

The RWTBBL series 11kV High-Voltage Filtering and Compensation Device strictly complies with relevant standards, including IEC 60871, IEC 60076, GB/T 30841.

Its core manufacturing process follows a strict and standardized sequence to ensure accurate harmonic filtering and stable compensation, with the steps as follows:

• Component Screening
• Modular Assembly
• Electrical Connection
• Commissioning and Calibration

The device is designed with three core technical highlights to adapt to the complex mining working conditions:

• Modular expansion for future capacity increase
• Redundant protection to avoid single point of failure
• Multi-branch coordinated switching for precise compensation

The specific manufacturing steps are detailed below.

2.1 Component Screening and Pretreatment

In line with the project’s 11kV voltage and 2000/1000/750kvar capacity requirements, core components (filter capacitors, reactors, intelligent controllers, switching devices) undergo strict quality screening, with precision deviation strictly controlled to ensure consistent performance of all parts.

On-site Core Component Screening and Anti-corrosion Treatment

2.2 Environmental Pre-treatment and Redundancy Design

Qualified components are treated with professional cleaning and anti-corrosion processes, with dustproof sealing and anti-vibration designs strengthened for the mining scenario. Redundant protection modules are configured for key core components to avoid the impact of single-point failure on overall equipment operation.

2.3 Modular Assembly and Fixation

The device adopts a scientific modular zoning design, with filter branches assembled independently in groups to realize independent operation and maintenance of each branch. Key structural and functional configurations are as follows:

• Core power components (capacitors, reactors) are firmly fixed on the cabinet frame to ensure mechanical stability
• Control components are centrally installed on the operation panel for convenient on-site operation and parameter adjustment
• Standard expansion interfaces are reserved between modules to support future equipment expansion demands when the mine increases its capacity
• A dedicated heat dissipation and ventilation structure is configured to adapt to the mine's high-temperature and high-humidity operating environment

On-site Electrical Connection and Insulation Testing of Equipment

2.4 Commissioning and Parameter Calibration

The intelligent controller is activated. The mine's harmonic working condition is simulated to calibrate sampling accuracy and switching thresholds. The multi-branch coordinated switching control strategy of filter branches is debugged. This ensures compensation accuracy and power grid stability. Protection functions, such as overvoltage, undervoltage, overcurrent, and harmonic overlimit, are all verified.

On-site Commissioning and Calibration of High-Voltage Filtering and Compensation Device

03 Testing and Inspection

A series of comprehensive tests have been carried out to verify the device's overall performance and environmental adaptability, with clear test criteria and quantified test results for each test item.

3.1 Temperature Rise Test

The temperature rise of core components (capacitors, reactors, busbars) under rated working conditions is strictly controlled to not exceed the IEC 60871 standard limit value (≤65K for metal parts). This verifies the device's excellent heat dissipation and thermal stability for long-term continuous operation, and fully adapts to the mine's 24/7 continuous production demand.

3.2 Environmental Adaptability Test

Tests including high and low temperature, damp heat, dustproof, and waterproof tests are conducted to simulate the mine's high-temperature, high-humidity, and dusty climatic environment. The device operates stably in all test environments, meeting the IP65 (outdoor) and IP54 (indoor) protection class requirements without any performance degradation. This verifies the device's strong operational stability under extreme working conditions.

3.3 Electromagnetic Compatibility (EMC) Test

The test is carried out in accordance with IEC 61000 electromagnetic compatibility standards to verify the device's high anti-electromagnetic interference capability. It effectively prevents controller malfunctions caused by power grid harmonics and external electromagnetic interference, and ensures the reliable and continuous operation of filtering and compensation functions in the complex electromagnetic environment of the mine.

3.4 Harmonic Withstand and Filtering Test

The device operates stably in a harmonic-rich environment (total harmonic distortion rate up to 15%) without any component damage or performance abnormalities, and can accurately filter the target 5th, 7th and 11th harmonic currents with a filtering efficiency of over 95%. This verifies the filter branch's excellent governance effect and fully adapts to the severe harmonic scenario of the mining area.

On-site Harmonic Withstand and Filtering Test of the Equipment

04 Packaging and Shipment

To address the vibration risk during overland transportation across thousands of kilometers of harsh road conditions in African mining areas, special packaging designs are adopted.

The equipment base adopts thickened channel steel. Filtering reactors and capacitor banks adopt a three-dimensional flexible support structure. These designs ensure no structural loosening or deformation occurs during bumpy long-distance transportation in Zambian mining areas. They effectively resist continuous bumps and impacts.

The whole equipment adopts export-specific heavy-duty packaging. This packaging is moisture-proof, shockproof, and dustproof. Core electrical components receive double-layer sealed moisture-proof protection.

The outside of the cabinet is equipped with a thickened and reinforced wooden packing case. It is filled with high-density buffer materials inside. This comprehensively resists severe vibration, dust erosion, and collision damage caused by ocean shipping and highway transportation in Zambian mining areas.

Spare parts are separately sealed and shipped with the goods. All equipment and accessories are clearly marked with project information, transportation identification, and installation numbers. This ensures full-process traceability. It guarantees that equipment is delivered to Jiangxi Copper Zambia's project site in Africa in good condition and on schedule, in accordance with project milestones.

On-site Custom Packaging for Export-specific Equipment

05 On-site Implementation and Summary

In light of the mine’s on-site conditions, RW Energy formulated a tailored implementation plan and deployed a professional technical team to provide full-process on-site services, ensuring the smooth completion of equipment installation, commissioning and handover.

5.1 On-site Installation and Implementation

RW Energy dispatched a professional technical team to the project site of Jiangxi Copper Zambia to provide full-process installation and commissioning services. The specific on-site work content is as follows:

• Guide the project party to complete the construction of equipment foundation and laying of grounding system, and install supporting hot-dip galvanized fences to ensure on-site safety protection.
• Complete the hoisting, positioning and fixation of the filtering and compensation device cabinet and reactor bank to ensure the levelness and mechanical stability of the equipment, adapting to the mine plant environment.
• Carry out the wiring and insulation test of high-voltage cables and control cables, verify the reliability of grounding, and complete the electrical connection between filter branches and the cabinet.
• Conduct on-site power-on commissioning, configure controller parameters, and verify the switching logic, reactive power compensation function and various protection logics of 5th, 7th and 11th harmonic filter branches.
• Conduct operation training for local operation and maintenance personnel, deliver operation and maintenance manuals, wiring drawings and technical data, and establish localized operation and maintenance capabilities.

5.2 Operation Feedback

After the equipment was put into operation, field actual measurement and third-party testing (tested by Zambia Bureau of Standards (ZABS)) show that it has been operating stably with no fault shutdown records. The test was carried out at the Point of Common Coupling (PCC) of the mine's 11kV busbar, with a continuous testing cycle of 72 hours, focusing on the detection of voltage total harmonic distortion (THD). All test indicators meet the requirements of IEEE 519-2014 and GB/T 14549-2018 power quality standards.

A comparison of core power quality indicators before and after commissioning is presented in the following table:

The project has passed the formal acceptance of Jiangxi Copper Zambia and the local power supply department, with all delivery indicators meeting or exceeding the project design requirements. The customer feedback states: "The high-voltage filtering and compensation device from RW Energy has completely solved the problems of excessive grid harmonics, voltage fluctuations, and high reactive power loss in the mining area. The overseas technical team provides professional and efficient services, which provides a solid power guarantee for the continuous production of the copper mine."

This project acceptance result and customer high recognition fully verify RW Energy's strong technical strength and professional service capabilities in the field of power quality governance for overseas mining in Africa. It provides a reliable filtering and compensation solution for the African mining market.

High-Voltage Filtering and Compensation Device in Stable Operation at Jiangxi Copper Zambia Project Site

06 Full Life Cycle Operation and Maintenance Trusteeship Service

The service adopts a full-process trusteeship management model with dedicated personnel responsibility, full-process control, traceable data, and closed-loop management, covering the following key service modules:

• Professional model selection and on-site adaptability evaluation before equipment installation
• On-site installation and commissioning with one-stop technical support
• 24/7 cross-border remote operation and real-time fault monitoring
• Regular quarterly on-site inspection and preventive maintenance
• Professional maintenance and repair for equipment abnormal conditions
• Rapid overseas emergency fault response and on-site rush repair
• Regular equipment condition assessment and life cycle management
• Professional guidance for equipment decommissioning and scrapping

A customized operation and maintenance plan is formulated for the high-temperature, high-humidity, and dusty operating environment of Zambian mines, with the following targeted supporting services:

• Establish an overseas spare parts warehouse in Copperbelt Province, Zambia for rapid supply of spare parts
• Conduct annual systematic re-training for local operation and maintenance personnel to improve professional capabilities

The service comprehensively ensures the safe and stable operation of equipment under complex working conditions. It extends the service life of equipment, reduces cross-border operation and maintenance costs of the mine, and provides users with reliable, efficient, and worry-free power support services.

If you need to obtain drawings, product specifications, selection manuals, installation instructions, and other materials, please contact us for further communication. We will provide you with customized solutions and efficient responsive services!