The new variants of the SD4S, SD4M and SD4B series from Sieb & Meyer will be on show for the first time at the SPS in Nuremberg. According to the company, in addition to optimized performance, higher speeds and low motor heating without sine filters are possible.

The 'SD4S' will be on show in 50 V, 230 V and 400 V class sizes. The available processor power has been used to increase the maximum output frequency to 4 kHz for synchronous motors and 6 kHz for asynchronous motors, as well as for new control functions. It is now possible to operate synchronous motors with "buried" magnets, also known as interior permanent magnet motors (IPM). The additional reluctance torque available for these motors is optimized in real time, independent of the operating point. The available communication interfaces - CANopen, Modbus RTU/TCP, EtherCAT, Powerlink and Profinet IO - allow integration into various application fields.

The 'SD4M' three-level inverters are used in turbo compressors and turbocompressors, among other applications, due to the low motor heating in combination with the high system efficiency. In addition, the elimination of motor chokes or sinusoidal filters reduces the construction volume and manufacturing costs of the overall system. The SD4M also offers the control function for IPM motors. Versions are available for AC and DC feed-in in a power range from 70 to 500 kVA. The versions with DC feed enable use in generator applications such as flywheels or micro gas turbines.

The particularly compact 'SD4B' is suitable for use as a highly dynamic servo amplifier for the operation of rotary and linear low-voltage servo motors as well as for optimized operation of high-speed low-voltage synchronous and asynchronous motors. In the high-speed range, the successor to the SD2B plus enables sensor-based operation of motors with a superimposed synchronization function based on 24 V synchronization signals. In this way, several high-speed motors can be operated synchronously in master/slave mode, which is helpful in the field of optical systems, for example. The robust speed control also allows high mass inertia ratios of up to 1:100 between motor and tool.