Abstract: Driven by the dual goals of environmental sustainability and economic efficiency, the port‑mining transport sector is undergoing a transformation led by electric technologies. At the heart of this shift is the adoption of all‑electric mining haul trucks, which are gaining increasing recognition for their zero emissions, low noise levels, and long‑term cost advantages. However, this transition also poses significant challenges for charging infrastructure.

Electric mining trucks and heavy-duty haulers typically feature high-capacity battery packs and high-voltage systems, which necessitate high-power charging infrastructure to support rapid charging. To address this challenge, the power systems at ports and mines must be upgraded. A common solution is to adopt a dedicated 10 kV high-voltage direct‑supply system.

Using a 10 kV high-voltage power supply allows direct connection to the charging system, enabling power delivery at the megawatt level to meet the demands of ultra‑fast chargers. This high‑voltage system can significantly improve charging efficiency and reduce the charging time for electric mining trucks and heavy‑duty vehicles, thereby enhancing overall operational efficiency.

In such a system, the charging terminal can deliver up to 1,500 V and 1,500 A, enabling the charging infrastructure to rapidly supply the high-capacity battery packs of electric mining trucks and heavy-duty haulers with the required energy. This high‑power charging capability is essential for ensuring that these electric vehicles can meet the demanding transportation demands of port and mining operations.

This paper discusses a megawatt‑class, high‑power supercharger system that is directly powered by the 10 kV high‑voltage network at a port‑side mine.

Keywords: Electric heavy-duty mining trucks; 10 kV high-voltage power supply; megawatt‑class charger; single‑gun charging current of 1,500 A; power distribution unit.

Introduction: In the port and mining transportation sectors, all‑electric mining trucks and heavy‑duty trucks are gradually becoming the new industry standard. As the battery capacity and voltage levels of these electric vehicles increase, the demand for charging system power rises accordingly. At present, to address this challenge, the power systems of port‑side mines have transitioned to direct supply from a dedicated 10 kV high‑voltage grid. This paper provides a detailed analysis of vehicle charging requirements and explores strategies for meeting these needs.

1. Meets the high-power charging requirements of various sites with a 10 kV domestic input:

To meet the high‑power charging demands of various domestic sites, the charging system must be compatible with and operate stably at an input voltage of 10 kV. This necessitates the use of high‑performance transformers and voltage regulation equipment to ensure input voltage stability and to accommodate diverse grid conditions.

2. Six‑channel, 240 kW single‑gun charging output; the six channels can be combined into a single circuit to achieve a power output of 1.5 MW.

The system is designed with six independent charging circuits, each capable of delivering 240 kW of charging power. When higher charging power is required, these six circuits can be combined into a single super‑charging circuit with a maximum output of 1.5 MW. This architecture ensures both the flexibility to charge multiple vehicles simultaneously and the ability to meet the high‑power demands of fast charging for individual vehicles.

3. Single-gun charging current: 1500 A; maximum voltage: 1500 V:

To meet the demands of high-voltage, high-current charging, charging gun designs must withstand currents of up to 1,500 A and voltages of up to 1,500 V. This places extremely stringent requirements on the materials, design, and manufacturing processes of the charging gun to ensure safety and reliability.

4. The charging output voltage is approximately DC 1500 V, with a battery capacity of 500–600 kWh and a charging rate of about 2–3 C.

Considering the voltage level and capacity of the battery pack, the charging system must be capable of delivering an output voltage of approximately 1,500 V DC to match the vehicle’s battery system. Meanwhile, with a battery capacity ranging from 500 to 600 kWh, the charging system is required to support charge rates of up to 2–3 C, which means it must be able to inject substantial amounts of energy into the battery within a relatively short time.

To meet the charging demands of all‑electric heavy‑duty mining trucks in port and mine transportation, the charging system must feature high‑performance power conversion and control capabilities, as well as a charging gun design capable of handling high voltages and large currents. Moreover, the system should offer robust compatibility and scalability to accommodate diverse charging requirements across different sites and vehicle types. With continuous technological advancements and innovation, there is every reason to believe that such charging systems will provide a solid foundation for the electrification of ports and mines, driving the entire industry toward greater efficiency and environmental sustainability.

II. Overall Design of a 10 kV High-Voltage Megawatt-Class Charging System

Based on several typical high‑power charging modules—such as 120 kW, 240 kW, 400 kW, 600 kW, and 1500 kW—we have designed standardized products to accommodate high‑power charging scenarios with varying power ratings and charging circuit configurations. The 1.5 MW high‑voltage charging system is planned as follows: a 10 kV supply enters a specialized rectifier transformer via a ring main unit; the transformer’s secondary side is configured to provide six 240 kW charging channels, supporting six 240 kW chargers (with an additional channel reserved for the station’s routine power consumption). Under the control of the monitoring unit, this system completes the entire charging service process. Its configuration is illustrated in the figure below.

Figure 1: 1.5 MW High-Voltage Charging System with Large-Power Charging Capability

III. Challenges in the Development of a 10 kV High-Voltage Megawatt-Class Charging System and Corresponding Solutions

In the port‑mining transportation sector, the widespread adoption of all‑electric mining and heavy‑duty trucks has placed heightened demands on charging infrastructure. Particularly when developing megawatt‑class charging systems, thermal management and high‑power module technologies have emerged as critical technical challenges. To address these hurdles, we have proposed a series of innovative solutions.

1. Independent ventilation and heat dissipation channel: To effectively manage the heat generated by megawatt‑class charging systems, we have designed dedicated ventilation and cooling channels. This design ensures that each module has its own dedicated heat dissipation path, with no interference between them, thereby maximizing the overall system’s thermal efficiency. Through precise computational fluid dynamics (CFD) simulations, we have optimized airflow to achieve rapid heat conduction and convective cooling.

2. Liquid-cooling system heat dissipation: For high-power supercharging stations, we have adopted a liquid-cooling system as the thermal management solution. Compared with traditional natural cooling, liquid-cooling systems offer more efficient thermal management. Through the circulating coolant, heat is rapidly removed and transferred to a location far from the charging module for dissipation. This design not only enhances heat dissipation efficiency but also reduces the operating noise level of the device.

3. Utilizes 120 kW IGBT charging module technology: To meet the requirements for high efficiency, stability, and long service life, we have adopted 120 kW IGBT (Insulated Gate Bipolar Transistor) charging module technology. An IGBT is a high-efficiency semiconductor device suitable for high-voltage and high-current applications. These modules deliver stable charging power while maintaining high energy conversion efficiency, thereby reducing thermal losses and extending the modules’ service life.

Through these technical measures, we have effectively addressed the challenges of heat dissipation and high‑power modules in megawatt‑class charging systems. This not only enhances the performance and reliability of the charging system but also provides robust technical support for the electrification of ports and mining operations.

IV. Composition of the 10 kV High-Voltage Megawatt-Class Charging System

4.1 High-Voltage Unit

High-voltage incoming switchgear; High-voltage metering cabinet; High-voltage outgoing switchgear;

4.1.2 High-Voltage Incoming Line

The 1.5 MW high-voltage integrated charging system for electric vehicles includes a high-voltage ring main unit, comprising one incoming feeder cabinet, one metering cabinet, and one outgoing feeder cabinet.

Under this scheme, metering is conducted at the high-voltage supply and high-voltage consumption points. A master meter is installed within the ring main unit, and the metering transformers are approved by the power supply authority. The electricity meters transmit energy consumption data via wired (or wireless) communication to the grid system (or other designated systems) for processing.

The system diagram of the three‑unit ring main unit is shown in the table below: (The final design shall be subject to the power supply authority’s plan.)

Figure 2: Single-line diagram of the three-unit ring main unit system

4.2 Substation Rectifier Unit

The technical parameters of the transformer are as follows: Technical Parameter Table for Three-Phase Special Rectifier Transformers (National Standard)

4.3、240 kW charging unit

The charging unit can achieve the following features:

• Within the full power range, the power factor and harmonic distortion shall be maintained within the limits specified by the relevant standards.
• It enables bidirectional energy flow and can be scaled into an integrated solar‑storage‑charging system, expanding both the range of energy sources and the breadth of application scenarios.
• The circuit is simple, with the secondary winding of the high-voltage transformer connected directly to the charger.
• Reliability assurance: the core modules are designed for a service life exceeding 15 years.
• Modular design ensures easy installation and commissioning, as well as simple operation and maintenance.

The logical schematic of the charging unit is as follows:

Figure 3: Logical Diagram of the Charging Unit

Technical Specification Sheet for 2 × 120 kW Charging Units

4.4 Charging Power Distribution Unit

As required, the 1.5 MW high-voltage charging power‑aggregation and dispatch unit employs a switch‑matrix topology, as shown in the figure below.

Figure 4 Schematic diagram of the power switch matrix

The following functions can be implemented:

• Normal output is 240 kW per fast-charging circuit.

• When a supercharging terminal has a charging demand, the system dispatches an idle circuit from among six available circuits to the supercharger, with a maximum output of 1.5 MW.

4.5 Charging Terminal

This 1.5 MW high-voltage charging system features six liquid-cooled charging terminals, one of which is a megawatt-class super terminal.

V. Conclusion

In today’s ports In the mining transportation sector, all‑electric heavy‑duty mining trucks are gradually replacing traditional fuel‑powered vehicles thanks to their environmental friendliness and high efficiency. These electric vehicles are equipped with high‑capacity batteries and high‑voltage battery packs to meet the demands of long‑duration, high‑intensity operations. Consequently, many port and mining operations have already adopted systems powered by standalone… 10KV In a high-voltage direct-supply power system, the system is directly connected to the charger, delivering substantial charging power.

This high-voltage power supply system design enables the charging terminal to support a maximum of 1500V the voltage and the maximum 1500A The current output and performance metrics enable the charging equipment to meet the diverse charging requirements of various electric vehicles. Whether charging with a single gun or simultaneously using four guns, the system delivers stable and efficient charging services. This significantly streamlines the charging process and addresses the challenges associated with multi-gun charging that heavy-duty electric trucks may encounter in real-world operations.

In the port and mining sectors, the widespread adoption of high-voltage power supply and multi-gun charging technologies has not only enhanced the operational efficiency of electric vehicles but also delivered substantial economic benefits. By reducing fuel consumption and lowering operating costs, these technologies have enabled enterprises to achieve significant cost savings. Moreover, from a societal perspective, they help curb greenhouse gas emissions, thereby advancing the green development of the port and mining industries.

Author Bio: Qin Jianji Director of Research and Development at Guangzhou Ruisu Intelligent Technology Co., Ltd., with a research focus on the industrial application of high‑power, megawatt‑class charging systems for electric vehicles in the port, mining, and metallurgical sectors, enabling high‑voltage, high‑power, autonomous plug‑in charging.

[1] Hu Chao , Zhang Hua , Luo Weiming , & Bao Hailong . (2009). Research on DC Charging Systems for Electric Vehicles . East China Power (10), 2014.

[2] Li Mengqi . Research on DC Power Supply Technology for Electric Vehicle Charging Stations . Dissertation Beijing Jiaotong University , 2013.

[3] Zhao Junliang . Research on DC-Connected Technology for Electric Vehicle Charging Stations [J]. Full-text version : Engineering Technology , 2016(6).  

[4] Yu Chen , Xu Hao , Wu Jingwei . A Power Supply System for Electric Vehicle Charging Stations Based on Solid-State Transformers :CN201710087591.4[P].CN106602565A[2024-04-07].

[5] Zhang Qingke , Zhang Wenqian . Exploration and Design of a Communication Protocol Testing System for DC Charging Stations for Electric Vehicles [J]. Metrology and Measurement Technology , 2023,

[6] Wang Xin , Sun Yutian , Zhang Huadong , Wait . Research on Fast Charging Systems for Electric Vehicles [C]// Shandong Society of Electrical Engineering Annual Academic Conference .2011.

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