distribution cabinets​ customized by the National Grid Company of Mozambique

  The distribution cabinets customized by the National Grid Company of Mozambique need to be designed specifically in combination with the local power infrastructure upgrade requirements, environmental conditions, and renewable energy development plans. The following analysis is carried out from aspects such as technical requirements, environmental adaptability, certification standards, and project cases:

 I. Technical Requirements and Functional Design

1. **Electrical Parameter Matching**

The power grid in Mozambique adopts the standard of **220V/50Hz**, and the distribution cabinet needs to meet the following core parameters:

- **Rated Voltage**: 220V (single-phase) / 380V (three-phase)

- **Short-circuit Withstand Current**: ≥50kA (adjusted according to the project capacity)

- **Protection Level**: IP54 (indoor) or IP65 (outdoor), suitable for dusty and rainy environments.

- **Intelligent Monitoring**: Integrated with real-time monitoring functions of current, voltage, and power factor, and supports remote data transmission (such as Modbus protocol) to meet the dynamic management requirements of renewable energy grid connection.

2. **Renewable Energy Compatibility**

Mozambique is accelerating the promotion of solar and wind energy projects, and the distribution cabinet needs to support:

- **Photovoltaic Grid Connection**: Equipped with an MPPT (Maximum Power Point Tracking) interface, compatible with the conversion between DC input and AC output.

- **Wind Power Access**: Configured with surge suppressors and frequency converters to deal with the voltage fluctuations of wind power.

- **Energy Storage Integration**: Reserve an interface for the Battery Management System (BMS) to support the charging and discharging control of energy storage devices.

3. **Modularity and Expandability**

Adopt the **MNS or GGD cabinet structure**, which supports the flexible expansion of the number of circuits (such as reserving 20% of the spare space) to meet the future load growth requirements. For example, the MNS-type distribution cabinets purchased for the titanium-zirconium ore project in Mozambique require copper busbars and a modular design.

 II. Environmental Adaptability Design

1. **Climate Protection**

- **High-temperature Heat Dissipation**: Adopt vertical busbar arrangement and forced air cooling system to ensure that the temperature rise is ≤65K in an environment of 40°C.

- **Moisture and Corrosion Protection**: The cabinet body is made of stainless steel or tinned steel plate, and the interior is sprayed with an anti-salt fog coating, which is suitable for high-humidity coastal areas.

- **Dust-proof Sealing**: The cabinet body with an IP65 protection level is equipped with a silicone sealing ring and a dust-proof filter to prevent dust from entering.

2. **Geographical and Power Grid Characteristics**

- **Power Grid Fluctuations**: Configure voltage stabilizers and overvoltage protection devices to deal with the problem of unstable voltage in the power grid of Mozambique (such as EDM's plan to improve power supply stability through gas-fired power plants).

- **Remote Areas**: Some distribution cabinets need to support off-grid operation and integrate diesel generator interfaces to ensure the continuity of power supply.

 III. Certification and Compliance

1. **International Standards**

- **IEC 61439**: The standard for low-voltage switchgear assemblies ensures the safety and reliability of the equipment.

- **CE Certification**: If it involves export, it needs to comply with EU directives, including EMC (Electromagnetic Compatibility) and LVD (Low Voltage) certifications.

- **CB Certification**: Certified through the IECEE system, which is convenient for entering the international market.

2. **Local Requirements**

- **SABS Certification**: Certified by the South African Bureau of Standards, and some projects may require compliance with African regional standards.

- **PROLER Plan**: Renewable energy projects in Mozambique need to comply with government bidding specifications, such as using local suppliers or joint ventures.

 IV. Reference of Typical Project Cases

1. **Distribution Cabinets Supporting the Temane Gas-fired Power Plant**

- **Function**: Supports the power distribution of a 400-megawatt gas-fired power plant, and is equipped with high-speed circuit breakers and an intelligent monitoring system.

- **Challenge**: It needs to be compatible with the existing Cahora Bassa Dam power grid to ensure a smooth transition.

2. **Distribution Cabinets for the Metoro Solar Project**

- **Design**: Integrates a photovoltaic combiner box and an energy storage system, and supports the grid connection and storage of 15-megawatt solar power generation.

- **Innovation**: Adopts smart meters and a prepayment system to improve power management efficiency.

3. **Distribution Cabinets for the Maputo Wind Farm**

- **Technology**: Configured with a dual-power supply switching device and a reactive power compensator to deal with the intermittent fluctuations of wind power.

- **Scale**: The distribution cabinets supporting the 120-megawatt wind farm need to meet the long-term stable operation of the 25-year Power Purchase Agreement (PPA).

 V. Supplier Selection and Localization

1. **Cooperation with International Brands**

- **Core Components**: Adopt circuit breakers and contactors of brands such as ABB and Schneider to ensure quality and compatibility.

- **System Integration**: Cooperate with Chinese enterprises (such as Wankong Electric) and combine with local service experience in Africa.

2. **Local Manufacturing and Training**

- **Assembly Factory**: Set up a cabinet assembly line in Mozambique to reduce transportation costs and create jobs.

- **Technical Training**: Provide maintenance training for local electricians to ensure the long-term reliable operation of the equipment.

 VI. Future Development Trends

1. **Intelligent Upgrades**

- Introduce AI algorithms to achieve fault prediction and automatic repair, reducing manual intervention.

- Integrate blockchain technology to optimize power trading and energy traceability.

2. **Green Manufacturing**

- Adopt energy-saving transformers and LED lighting to reduce its own energy consumption.

- Promote recyclable materials to reduce environmental impact.

3. **Microgrid Integration**

- Support the access of microgrids in rural areas to improve the power coverage rate (Mozambique plans to increase the coverage rate from 34% to 63% in 2024).

Conclusion

The distribution cabinets customized by the National Grid Company of Mozambique need to take into account technical performance, environmental adaptability, and local requirements. Through modular design, intelligent monitoring, and renewable energy compatibility, the distribution cabinets will become the core components of its power infrastructure upgrade. At the same time, the combination of international certification and local manufacturing can ensure the economy and sustainability of the project.