110kV Power Transformer Enables Stable Power Supply for a Large Industrial Park in Vietnam: Solving Capacity Shortages and Voltage Fluctuations

Background: Power Supply Bottlenecks in Vietnam’s Industrial Hub

Binh Duong Province is a core manufacturing region in Vietnam, hosting numerous electronics, semiconductor, and automotive component enterprises. In 2022, Vietnam Tech Park, a key tenant within the zone, faced critical power challenges:

• Severe Capacity Shortfall: The existing 35kV substation operated at 120% of its rated load, preventing connection of a newly commissioned wafer packaging production line.
• Frequent Voltage Fluctuations: During peak hours, the 10kV bus voltage dropped to 9.2 kV (standard: 10.5 kV), causing precision equipment to shut down unexpectedly—resulting in average monthly losses exceeding $150,000.
• Limited Expansion Space: Land constraints made it impractical to build additional 35kV substations, necessitating a high-density, high-reliability primary voltage upgrade solution.

Solution: Deployment of a 110kV/200 MVA Three-Phase Dual-Winding Power Transformer

With support from Vietnam Electricity (EVN), the project team partnered with TBEA (China) to implement a comprehensive upgrade centered on:

• One 110kV/200 MVA oil-immersed power transformer (Model: SSZ11-200000/110), equipped with on-load tap changer (OLTC ±8×1.25%).
• Integrated 110kV GIS (Gas-Insulated Switchgear) and a smart SCADA system for remote monitoring and rapid fault isolation.
• Low-noise design (≤65 dB) and triple-explosion-proof tank construction to meet stringent environmental and safety regulations within the industrial park.

Technical Highlights and Customer Value

• Single-Step Capacity Resolution:
  • One 110kV transformer replaced three legacy 35kV substations, saving 40% of land area while reserving 30% future expansion capacity.
• Precision Voltage Regulation:
  • The OLTC dynamically adjusts output in response to load variations, maintaining 10kV bus voltage within ±1%, eliminating equipment malfunctions.
• High Reliability and Energy Efficiency:
  • No-load loss ≤85 kW; load loss ≤320 kW (at 75°C), compliant with IEC 60076 standards—saving approximately 1.2 million kWh annually.
  • Integrated DGA (Dissolved Gas Analysis) online monitoring enables early detection of incipient faults.

Implementation Outcomes

• Enhanced Power Capacity: Maximum park load increased from 85 MW to 180 MW, enabling the successful onboarding of two Fortune 500 electronics manufacturers.
• Voltage Quality Achieved Compliance: 10kV bus voltage compliance rose from 96.3% to 99.8%, with zero unplanned equipment shutdowns since commissioning.
• Significant Economic Benefits:
  • Annual avoided production losses exceed $1.8 million;
  • Improved transformer efficiency reduces annual electricity costs by approximately $75,000.

Client Testimonials

“The 110kV power transformer was the cornerstone of our park’s upgrade. Even during peak demand, our production lines have never experienced interruptions due to voltage instability.”
— Mr. Nguyen Van Hieu, Facility Director, Vietnam Tech Park

“From contract signing to energization in just five months—TBEA’s 110kV transformer not only met but exceeded our performance expectations.”
— Ms. Le Thi Mai, Project Manager, EVN Southern Power