Nidec ASI Silcovert TH series medium voltage drive

The Silcovert H Series (TH/NH) is the ideal variable speed drive solution for retrofitting to improve efficiency and reduce environmental impact. It is a multi-level variable speed drive with IGBT power devices and a more efficient and precise control for induction and synchronous motors. The PWM technique with high switching frequency allows an almost sinusoidal motor current with low total losses and very low torque. Its water cooling method permits to achieve high output power ranges. Our H series variable speed drives are compatible with existing motor systems, regardless of brand or age. With our customized retrofit customers can achieve increased levels of safety, reliability and efficiency.

Power range:

Air cooling: up to 8100 KVA

Water cooling: up to 21000 KVA

Voltage: up to 4160/6000/6600/7200 V

Output Frequency: 5 – 250 Hz (330 max with derating)

Nidec (formerly Ansaldo) makes a medium voltage VFD with a rating of 25,000 HP. This is a voltage source VFD. (almost everyone else making a 25,000 HP VFD is using a current source VFD)nidec-silcovertthVoltage Source medium voltage VFDs offer a big advantage over current source, and especially in the 25,000 HP VFD range. Many manufacturers make voltage source medium voltage VFDs in the 10,000 HP range and below.

But there are applications that require larger horsepowers, such as Gas Compressors, and the air gets more rarefied when hunting medium voltage VFDs above 10,000 HP. And, in voltage source medium voltage VFDs, it’s rare indeed.

Nidec (formely Ansaldo) has been building very large horsepower medium voltage VFDs for some time. EMA is proud to be a distributor and service center for Nidec’s large horsepower medium voltage VFDs.

The Nidec/Ansaldo Silcovert TH is based on Cascaded H-Bridge multilevel topology. This design is similar to what you will find in the Robicon/Siemens Perfect Harmony MV VFDs. This is a 7 level topology.