New energy charging piles exhibit significant load impact, high instantaneous current, and dense harmonics, constituting a special type of pulsating load. The supporting transformers require specialized design and adaptation:
1. Adequate capacity reservation: Charging piles are intermittent impact loads, and the load increases sharply when vehicles are charging collectively. Therefore, the selection of charging piles should reserve a margin of more than 40% to avoid peak overload, tripping, and excessive temperature rise.
2. Anti-harmonic and anti-shock design: The rectifier module of the charging pile generates a large amount of harmonics. The equipment adopts optimized winding and core structures to reduce harmonic losses and avoid local overheating and premature equipment failure.
3. Load adaptation design: It adapts to imbalanced and sudden loads, with stronger resistance to short-term overload, meeting the peak charging conditions during holidays and nighttime.
4. Equipment selection specifications: For residential charging piles and public charging stations, priority should be given to low-noise, low-loss oil-immersed or dry-type transformers; for large centralized charging stations and high-speed charging stations, a combination of dedicated distribution transformers and box transformers should be adopted, ensuring convenient operation and maintenance and high safety.
5. Protection standards: The supporting equipment for outdoor charging piles must possess waterproof, dustproof, sunscreen, and temperature difference resistance properties, suitable for open public settings.
