1. A 400 kVA transformer is typically capable of powering a load of approximately 320 kW.
2. Under light load conditions, the transformer operates stably with a load factor between 0.5 and 0.7, which also represents the optimal economic performance.
3. The efficiency of the transformer reaches its peak when the load factor is between 63% and 67%. Consequently, it is common practice to match the load to 80% of the transformer's apparent power, which is why a 400 kVA transformer can typically be matched with a 320 kW load (400 kVA x 0.8 = 320 kW).
4. The selection of transformer capacity should be based on the calculated load. The load factor is the primary consideration when determining transformer capacity. The transformer operates most efficiently when its no-load loss equals the square of the load factor times the load loss, but this is only from an energy-saving perspective and not comprehensive.
5. In selecting transformer capacity, other economic costs associated with running the transformer should also be considered, including fixed asset investment, annual operating costs, depreciation, taxes, insurance, and other expenses. Sometimes, to reduce the number or size of transformers, it is appropriate to raise the transformer's load factor,尽管this may牺牲 some operational efficiency, but it can lower the initial investment.
