630 Kva Dry Type Indoor Electrical Power Transformer

The 630 kva dry type indoor electrical power transformer is a new generation of low noise and low loss transformer developed in recent years. Its iron core is seamlessly connected, which significantly reduces no load losses and no load currents. The high and low windings are continuously wound around the iron core column, with the windings tightly wound, which further enhances the compactness of the product.  The continuous winding cross section of the iron core is circular, which can fully utilize the orientation loss of silicon steel sheets, thereby reducing the  no load loss by 20%.

Transformer Workshop

Substation Workshop

Assemble Workshop

630 kva dry type indoor electrical power transformer features high mechanical strength, strong short circuit tolerance, excellent dust proof and anti fouling performance, and has a longer service life than other dry type transformers. Moreover, the low voltage coil is made of a foil wound structure with high quality steel foil. The high voltage coil adopts vacuum epoxy resin casting technology to form a layered structure, which results in a lower local discharge rate.

Technical parameter:

Testing Center:

To supply a smooth acceptance and user experience, WenZhou XiFa electric Power Equipment Co., Ltd. would 100% inspect of all items in accordance with the IEC 60076-11 standard before shipping to ensure electrical and insulation properties of a 630 kva dry type indoor electrical power transformer is ready for use. Each dry type indoor electrical power transformer would equip with a IP23 or IP31 protection enclosure.

Testing Center

Inspection Waiting Area

Transformer in Testing

Winding Workshop:

Wenzhou XiFa Electric Power Equipment Co., Ltd. could produce the 4000 kva 33/0.4 transformer winding for oil immersed transformer and cast resin transformer. And also the company could produce the winding of 25 mva OLTC ONAN transformers. In our winding workshop, the foil winding machine could produce Low voltage winding for 400 kva to 4000 kva cast resin transformers. Meanwhile, more than 200 sets of winding would be produced within 30 days in Wenzhou XiFa Electric Power Equipment Co., Ltd.

Foil Winding Machine

Winding Workshop

Transformer in Winding

Product Maintenance:

After being connected to the power distribution system, the 630 kva dry type indoor electrical power transformer needs to be synchronized with the implementation of reactive power compensation and harmonic control.

In terms of reactive power, an intelligent dynamic compensation device is configured on the low voltage side, with the compensation capacity selected at 25% to 38% of the transformer capacity. The power factor is stabilized at above 0.90, and controlled at 0.92 to 0.95 during peak hours. Excessive compensation is strictly prohibited. The capacitor circuit must be series connected 6% to 12% reactors to suppress the closing surge current and resonance risks. The equipment layout should reserve ventilation space to avoid blocking the 630 kva dry type indoor electrical power transformer air ducts.

Transformer Oven

Casting Mould

Casting Machine

Harmonic control must comply with the GB/T 14549 standard. The total harmonic distortion rate of the low voltage busbar voltage should be ≤ 5%. This 630 kva dry type indoor electrical power transformer can suppress third and higher order zero sequence harmonics, but still needs to focus on controlling 5th and 7th harmonics. For normal loads, an electric reactor can be used. For moderate harmonic conditions, an passive filter should be added and in high harmonic scenarios, an active filter should be installed. At the same time, the cross sectional area of the neutral line should be increased, and harmonic source equipment such as frequency converters and rectifiers should be separately arranged.

During operation, online power quality monitoring should be combined, and the temperature control and partial discharge data of the 630 kva dry type indoor electrical power transformer should be linked for control to prevent problems such as winding overheating, insulation aging, and increased noise caused by harmonics, which ensures the long term stable operation of the equipment.