Life Cycle Cost Analysis and Maintenance Strategies for Oil-Immersed Transformers
Time：2025-04-21 Auther：ZTelec-www.ztelectransformer.com
1. Initial Investment Cost
The initial investment cost includes equipment purchase, installation and commissioning, and specialized testing fees, detailed as follows:
Equipment Purchase Fee: Includes the purchase price of the oil-immersed transformer itself, on-site technical service fees, special tool costs, initial spare parts costs, logistics and transportation costs, relevant taxes, and insurance fees, etc.
Installation and Commissioning Fee: Covers transformer foundation construction costs and pre-commissioning system debugging costs.
2. Operating Costs
Operating costs consist of energy efficiency losses and environmental protection expenditures:
Energy Efficiency Costs: Derived from no-load losses (core losses) and load losses (copper losses). The calculation formula is:
Energy Efficiency Cost in Year a = No-Load Loss Cost + Load Loss Cost
Environmental Protection Costs: Determined based on actual environmental compliance expenditures (such as waste oil disposal costs for oil-immersed transformers).
3. Routine Maintenance Costs
Daily Inspection Costs: Includes depreciation of testing equipment, consumable costs, and labor costs (oil-immersed transformers require regular oil chromatographic analysis).
Regular Maintenance Fees: Adjusted according to manufacturer maintenance procedures and actual operating conditions.
4. Failure Repair Costs
Direct Repair Costs: Includes costs for dismantling faulty equipment, transporting and installing new transformers, etc. (repair costs for oil-immersed transformer winding faults are typically higher than for dry-type transformers).
Indirect Losses: Economic losses due to power outages and emergency procurement premium costs.
5. Retirement Disposal Costs
Disposal Costs: Involves equipment dismantling and hazardous waste treatment (insulating oil from oil-immersed transformers requires professional recycling).
Residual Value Revenue: Calculated based on total weight × current scrap copper and steel recycling price.
Cost Influencing Factors
Equipment Specifications: Maintenance costs for 220kV and above oil-immersed transformers are 40%~60% higher than for 10kV class transformers.
Fault Level: The disposal cost of insulating oil deterioration (accounting for 32% of the failure rate) is higher than that of bushing partial discharge.
Regional Differences: Labor and emergency transportation costs in remote areas can increase by 30%.
Typical Cost Range
The single repair cost of oil-immersed transformers is usually 5,000~300,000 RMB, and the overhaul cost can reach 15%~20% of the original equipment value.
Optimization Recommendations
By implementing condition-based maintenance (such as online oil monitoring) and selecting high-reliability oil-immersed transformers (such as those using natural ester insulating oil), the total life cycle cost can be reduced by 18%~25%.
