The exhibitors of the SPS 2026 are expected to be published in spring 2026. Until then, you can find the exhibitors and products of the SPS 2025 here.
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SD4M Multilevel Frequency Converter
SD4M Multilevel Frequency Converter
Description
A combination of proven technology with the latest control and communication technology. The device variants of multilevel converter SD4M in the range from 70 kW to 490 kW or 120 A to 800 A rated current correspond to their SD2M counterparts in terms of power electronics. The devices are all very compact, which is an important requirement in the field of high-speed turbo machinery.
In addition to high-speed turbomachinery, the SD4M is very well suited to high-performance routing machines for HSC, as they are frequently used in the aerospace industry, for example. The multiprotocol real-time Ethernet interface available on the device (including PROFINET IO, EtherCAT) enables hassle-free implementation of the SD4M in the higher-ranking control. An optimal operation with an external regenerative power supply is possible using the variants with DC supply.
The SD4M with the new power class (70 kW, 120 A) extends the current power range of SD2S and SD4S and thus closes the performance gap in the frequency converter portfolio.
In addition to the water-cooled variants, air-cooled devices are available on request. NRTL/CSA certification is applied for all devices, which is relevant for customers exporting machines to North America.
The SD4M Turbo versions offer another special highlight for use in turbo blowers and turbo compressors: optionally, active magnetic bearings can be supplied with the required DC voltage via clamp connections – this voltage is maintained for braking even in the event of malfunctions. Another highlight is the new dynamic control of IPM motors, which offers customers further degrees of freedom when it comes to the system conception.
The innovative three-level technology of the frequency converter SD4M in combination with device-dependent switching frequencies of up to 32 kHz ensure an excellent current quality, which reduces motor losses and increases the overall efficiency. This prevents excessive rotor heating and reduces the load on the bearings as well as insulation stress. Thanks to the frequency converter, customers can do without expensive motor chokes or sine-wave filters.




