1. System Background

With the rapid urbanization, modern transportation systems like subways and light rails have become a key part of city infrastructure. To ensure the stable and safe operation of subway systems, the power supply system must be highly reliable and resilient. Especially in the event of power outages, equipment failures, or other emergencies, it is crucial to ensure uninterrupted power for critical systems to avoid operational disruptions.

2. Basic Requirements

The DC power supply system for subways must meet the following essential requirements:

• Uninterrupted Power Supply: Ensure that lighting, monitoring, and data systems continue to receive stable power even during power outages.
• High Reliability: The system must be equipped with automatic switching, over-voltage protection, over-current protection, and other safety functions to ensure the safety and proper functioning of the equipment.
• Intelligent Monitoring: The system should feature real-time monitoring and fault warning capabilities to ensure smooth operation and easy management.

3. Solution Architecture

To meet these needs, EVEREXCEED provides a complete DC power supply system featuring high-performance uXcel Phase-Control Rectifiers and HF Series High-Frequency Switch Rectifiers, combined with advanced battery banks and DC distribution equipment. The system will include the following key components:

a) DC Rectification Module

• uXcel Phase-Control Rectifier: Converts AC power from the AC distribution panel to DC power, supplying power to subway systems such as lighting, monitoring, and data systems. The uXcel rectifier offers high efficiency and stability, capable of handling voltage fluctuations from the grid and ensuring stable DC power output.
• HF High-Frequency Switch Rectifier: Ideal for systems with strict size and weight requirements, it provides higher conversion efficiency and occupies less space.

b) Battery Bank

• The battery bank is connected to the DC distribution panel and used for backup power. In the event of AC power failure, the battery bank automatically discharges to continue powering communication, lighting, monitoring, and other critical systems, ensuring that power is not interrupted. When AC power is available, the battery bank remains in floating charge mode, acting as a large capacitor to filter out any noise voltage from the rectifier and maintain high-quality DC power.

c) DC Distribution Panel

• The DC distribution panel is equipped with connections for two sets of batteries and supports parallel use. It features over-voltage protection, over-current protection, low voltage alarm, and other safety functions.
• The distribution panel supports intelligent monitoring, allowing real-time monitoring of key parameters such as DC output voltage, battery charging/discharging current, and current from individual subcircuits.
• The system can remotely detect and alert users in case of abnormal voltage, fuse failure, low battery voltage, or breaker trip.

4. System Features

• Redundancy Design: The DC system adopts a two-battery parallel design to enhance reliability, ensuring that the system continues to function even if one battery fails.
• Overload Protection: Both the DC distribution panel and rectifiers are equipped with overload protection to prevent equipment damage from excessive load.
• Energy Efficiency: uXcel Phase-Control Rectifiers and HF High-Frequency Switch Rectifiers provide high conversion efficiency, reducing energy loss and improving overall system economics.
• Smart Management: The integrated intelligent monitoring system allows subway operators to view real-time data on the power supply system’s status, enhancing maintenance efficiency and response time.

5. Technical Specifications

• DC Output Voltage: The system can be customized to provide different DC voltage outputs based on the specific needs of systems like lighting, monitoring, and communication.
• Current Range: The rectifiers and battery bank can adjust the output current to meet the varying load requirements of different subsystems.
• Battery Charging Mode: The system supports both floating charge and equalization charge modes, ensuring long battery life and optimal performance.

6. System Operation & Maintenance

• Real-Time Monitoring & Alarming: Through the integrated monitoring system, operators can monitor the DC power supply system 24/7 and address any potential issues before they lead to downtime.
• Routine Maintenance: Regular health checks of the battery bank are recommended to ensure long-term stable operation.
• Automatic Switching & Redundancy: In case of a power outage or equipment failure, the system automatically switches to battery power, ensuring no interruption in critical operations.

7. Application Benefits

This DC power supply system effectively addresses the power reliability issues in subway systems, ensuring continuous operation of lighting, monitoring, and data systems even during power failures. Additionally, the intelligent monitoring and fault detection capabilities significantly improve operational efficiency and response time, helping reduce risks and maintain safe and smooth transportation operations.