
I. Background and Challenges
Shore power systems have become core technical equipment for ports to reduce carbon emissions and noise pollution. However, these systems face two major challenges in the harsh operational environment of ports:
- Severe Environmental Corrosion: High humidity and salt spray in port areas cause serious corrosion to metal components and enclosures of electrical equipment, significantly impacting electrical lifespan and operational reliability.
- High Switching Requirements: Connecting ships to shore power requires fast, smooth, and shock-free switching between the grid power and the ship’s generator power. Any delay or current surge during switching may jeopardize the safety and stability of both the ship’s power system and the port grid.
To address these challenges, our company has introduced an integrated vacuum contactor solution specifically designed for port shore power systems, ensuring fundamental reliability and efficiency.
II. Core Solution
This solution centers on high-performance vacuum contactors, customized with a series of technical features to perfectly meet the demands of port shore power applications.
- Corrosion Protection Design for Salt Spray Environments
• Stainless Steel Enclosure: The contactor body is housed in a high-grade stainless steel enclosure, offering exceptional resistance to salt spray, moisture, and corrosion, ensuring long-term stability in harsh port conditions.
• Silver-Plated Contacts: The conductive circuits inside the vacuum interrupter and key external connection points are silver-plated, significantly reducing contact resistance, improving conductivity, and preventing poor contact or overheating caused by oxidation and electrochemical corrosion, thereby extending electrical lifespan.
- Fast and Seamless Power Switching
• Pre-charging Device: An integrated pre-charging circuit charges the transformer and cables on the ship’s load side through a pre-charging resistor before the main contactor closes, effectively suppressing the large inrush current during switching.
• Ultra-Fast Switching Performance: An optimized electromagnetic system combined with a vacuum interrupter achieves a switching time of less than 50 milliseconds (ms). This far exceeds the performance of traditional contactors, ensuring smooth and imperceptible power switching without impacting sensitive shipboard equipment.
- Intelligent Control and System Integration
• Integrated PLC Control Unit: A built-in high-performance programmable logic controller (PLC) serves as the local control brain, precisely managing the timing and logic of pre-charging, closing, and opening operations.
• Automatic Grid Synchronization Function: Through PLC programming, the system实时 monitors voltage, frequency, and phase differences between the grid and ship power, automatically issuing switching commands when conditions are met. This enables fully automatic grid synchronization, significantly reducing manual operations while enhancing safety and efficiency.
III. Application Results and Case Study
This solution has been thoroughly validated in practical projects, delivering remarkable results.
Case Study: PSA Singapore Port Project
• Duration of Application: Stable operation for over 3 years.
• Reliability Record: Achieved a "zero failure" operational record, fully demonstrating the solution’s exceptional reliability and durability under high-intensity and highly corrosive conditions.
• Efficiency Improvement: The fully automatic fast-switching mode significantly streamlined the ship power connection process, improving average connection efficiency by 40%. This effectively reduced vessel berthing time, delivering substantial economic benefits for both the port operator and ship owners.
IV. Conclusion
This vacuum contactor solution addresses the core challenges of port shore power systems through material innovation (stainless steel + silver plating), technical integration (pre-charging + PLC), and performance optimization (<50 ms switching). It is a critical equipment choice for ensuring the safe, reliable, and efficient operation of shore power systems. We are committed to providing globally proven intelligent electrical connection solutions for port customers worldwide, supporting the green transformation and upgrading of ports.