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One advantage of using a WEG MV01 Medium Voltage VFD

The 20 year typical cost of ownership on a large AC motor is shown on the chart below. We can realize significant savings on variable torque type loads by using medium voltage VFDs.

20yearcycle90 percent of the cost of large motors is power usage. There are also additional costs associated with running large medium voltage VFDs, such as air-conditioning and in some cases E-houses. We can further complement the energy savings from applying VFDs IFwe can reduce the air conditioning costs as well.

Unlike low voltage VFD design, medium voltage VFD design varies from one manufacturer to another. As a service partner of WEG, EMA does both repairs and start up on the WEG MVW01 medium voltage drive.

Handling the heat on a large MV VFD is a significant part of the life cycle cost of owning large medium voltage VFDs.

IMG00917Some MV VFD manufacturers design the VFD such that the phase shifting transformer is integrated inside the MV VFD cabinet. This approach, while it makes sense and works very well in some cases, may not be ideal for all MV VFD applications.

Foot print/space is often an issue in most plants along with getting rid of heat in the electrical room. The WEG MVW01 VFD is packaged such that the VFD could be supplied separately from the phase shifting transformer. Where foot print is an issue and space is readily available outside the e-house or electrical room, WEG can supply a NEMA 3R phase shifting transformer which can be mounted outside and separate from the MVW01. This can not only save space but reduces the life cycle cost of owning the MV VFD by lowering the air conditioning cost required for getting rid of the heat presented by the phase shifting transformer.

Typical heat losses for VSI (Voltage Source Inverters) is roughly 37 HP per 1000 HP VFD capacity, so getting rid of the excess heat that is generated by the inefficiencies of the VFD package is an important part of any large VFD project. Part of the 37 HP losses is due to the heat generated by the 873 KVA phase shifting transformer typically used on a 1000 HP VFD.

The WEG design works well and it is an efficient solution where space is an issue inside the electrical room. It reduces the overall heat losses in the E-house or building, which results in an overall reduction of air conditioning cost.

EMA is a preferred service partner for WEG and familiar with the WEG MVW01 MV VFD. We also perform service work on the CFW09, CFW11, CFW700, CFW500 and CFW08. Contact us if you need help on your WEG MVW01 or WEG MVSS and low VFDs.

Contact us by any of the contact methods on the right of this page, or call 770-448-4644770-448-4644.

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