Intelligent Evolution of Rail Transit Power Systems and Revolutionary Whole-Life Cycle Maintenance

I. System-Level Solutions: From Single-Point Breakthroughs to Global Optimization

1. Intelligent Scheduling and Energy Synergy
   • The improvement of rail transport efficiency relies on the optimization of multiple systems working together. Xi’an Metro Line 8, for example, has integrated fully automatic driverless technology (GOA4 level) with sensor-less vector control technology in its electrical traction system. By dynamically adjusting the motor control accuracy, energy consumption is reduced by 12%, and parallel power supply redundancy backup is achieved. RailMac provides power module compatibility solutions in such projects, enabling customers to seamlessly upgrade high-frequency auxiliary power supply units on their existing converter platforms. The new units are 30% smaller in volume and 45% lighter in weight, saving up to 8 million yuan in electricity costs annually for a single line. The solution also incorporates regenerative braking feedback technology (with an efficiency of 85%), converting braking energy into a power source for on-board equipment and alleviating peak-load pressure on the power grid.
   • RailMac, as a provider of power technology solutions, is driving the transformation of traditional power chains towards an integrated “sensing – decision – action” architecture by participating in the process with system adaptation and scenario-based integration.
2. Environment-Adaptive Control System
   • Stability in extreme environments is a key requirement for overseas projects. In Southeast Asia’s hot and humid regions, light rail systems commonly face issues such as electronic component oxidation and reduced heat dissipation efficiency. A three-layer protection scheme is adopted to address these problems: the hardware layer strengthens corrosion-resistant coatings and multi-stage air filtration; the software layer incorporates temperature and humidity compensation algorithms; and the service layer configures a dynamic adjustment mechanism for remote diagnosis thresholds. This solution has extended the fault-free interval mileage of equipment on Malaysia’s Kuching line by 40% and reduced maintenance costs by 22%.
3. Intelligent Integration of Passenger Services
   • Qingdao Metro Line 6 demonstrates the service upgrade path of “intelligent agents + large models”. Its station-based intelligent agents possess the “Visual Explanation of All Things” function, which can locate target passengers within seconds, improving the efficiency of traditional passenger searches by 70%. RailMac assists customers in building a closed-loop service response chain: multi-modal sensors (such as passenger flow density cameras and acoustic collection devices) are deployed at the front end; scenario-specific lightweight AI models are trained at the mid-platform; and the back end is connected to ticketing, security check, and emergency broadcast systems. This enables a 90-second response from demand sensing to resource allocation.

II. Whole Life Cycle Maintenance Support: Data-Driven Value Extension

1. Predictive Maintenance Ecosystem Development

• Chengdu Metro has pioneered a smart maintenance system of “one network and three centers”, integrating data from 16 depots through a maintenance data transmission network and building a closed loop of online monitoring – operation and maintenance analysis – intelligent scheduling. This supports the implementation of a three-tier fault prediction architecture for customers.
  • Sensing Layer: High-precision vibration sensors are installed in bearings and gearboxes, with a sampling frequency of up to 10 kHz to capture early failure characteristics.
  • Analysis Layer: Deep learning models are trained based on historical fault libraries, reducing the false alarm rate to below 5% (such as identifying insulation aging risks through acoustic fingerprint recognition).
  • Decision-Making Layer: A dynamic work order system automatically allocates spare parts and manpower based on the remaining life of components (with a prediction error of less than 3%), improving the maintenance efficiency of Shanghai Metro’s signaling system by 40%.

2. Cross-Domain Collaborative Emergency Response
   • The disposal of complex faults depends on the coordination of multiple disciplines. Shanghai Metro has established a “cloud – pipe – end” emergency architecture: a digital twin platform is deployed in the cloud to rehearse response procedures; real-time control commands are transmitted through a 5G dedicated network; and terminals use AR glasses to overlay assembly/disassembly instructions. The remote support package provides three core capabilities.
     • Expert Knowledge Base: It encapsulates the logic trees of disposal procedures for 3,000+ fault cases to guide on-site personnel in standardized operations.
     • Resource Collaboration Map: Based on GIS, it dynamically displays the distribution of emergency materials and repair paths.
     • Cross-System Reset Protocol: It supports remote restart authorization for key systems such as signal interlocking and power supply ring networks. This solution has reduced the mean time to repair (MTTR) for major faults from 4.2 hours to 1.8 hours.

III. Global Implementation: The Philosophy of Localization-Compatible Technology

1. Infrastructure Compatibility Design
   • Emerging markets often face challenges such as power supply fluctuations and insufficient track precision. A wide-range voltage stabilization scheme can be adopted, which uses power electronics conversion technology to filter out 30% of voltage harmonics and achieves a 10-ms seamless transition during dual-power-supply switching. This ensures the train’s traction performance under grid fluctuation conditions of ±25%. Some projects customize rack-rail power packages to maintain a cruising speed of 80 km/h on steep gradients of 12%, a 50% speed increase over traditional solutions.
2. Modularization to Lower Technical Barriers
   • To overcome the dilemma of varying levels of technical reserves among customers, solution providers need to promote interface standardization. China’s standard metro trains (120 km/h Type B) have achieved 100% unification of traction/braking interfaces, increasing the generalization rate of maintenance tools by 50%. Based on this, plug-and-play power modules (200 kW/400 kW) have been developed, enabling customers to complete power unit replacement within 48 hours, a 70% reduction in the traditional retrofitting cycle.
3. Knowledge Transfer for Long-Term Operations
   • The core of technology implementation lies in matching personnel capabilities. A three-tier training system has been implemented in some projects
     • Operational Level: A VR simulation platform imitates 30 fault scenarios to train basic maintenance skills.
     • Management Level: Digital dashboards teach equipment health evaluation methodologies.
     • Decision-Making Level: Energy consumption analysis tools guide the optimization of life-cycle costs. This system enables local teams to achieve independent operation and maintenance capabilities within six months, with customers having a renewal rate of over 90% for three consecutive years.

IV. Future Layout: The “Three-in-One” Integration of Power Systems

• Modularization: Develop standard power units (such as 200 kW/400 kW modules) that can be flexibly combined to meet the requirements of different types of rolling stock.
• Fuel-Neutralization: Enable the same engine platform to be compatible with hydrogen, ammonia, and biodiesel to reduce customers’ energy-switching costs.
• Intelligent Maintenance: Create engine health profiles based on blockchain technology to enable component traceability and carbon footprint tracking.