Industrial Systems

Dynamic spin dynamo Low-Inertia Motor (DSD Series)



These motors boast super low inertia and are optimal for servo applications and automotive testing.

Sample configuration of dynamo equipment for automotive testing

These dynamos enable you to build test systems that shorten development schedules and improve performance in the development of next-generation automobiles. We support systems with all sorts of configurations based on our customers’ requirements. Please contact us for more information.


Lowest inertia in the industry

To reproduce the responsiveness of an engine, we pursued low inertia even further based on a low-inertia permanent magnet sync motor (ED motor). The inertia moment (J) of our S-DSD series motors is one-tenth that of other motors with the same output.

Comparison of inertia values between an induction motor and S-DSD

Types Output Base rotating speed Inertia (J)
Max rotating speed
Induction motor 220kW 4,000min-1 0.73kg・㎡
S-DSD 220kW 4,000min-1 0.073kg・㎡

Transient operation on the level of a real vehicle

Combining a low-inertia S-DSD series dynamo with a VF66C high-response inverter enables a torque frequency response of 2.4 kHz. This makes it possible to better reproduce behaviors that approach actual automobile engines.
*See here for more in depth specifications.

VF66C high-response inverter

VF66C high-response inverter

Capable of being attached under the same conditions as an actual vehicle

Size and weight have been dramatically reduced compared to ordinary ED and UF motors. Configurations that approximate an actual vehicle, which has been impossible in the past, such as FF transaxel testers, are now possible. And when combined with a drive mechanism that moves up, down, and side to side, tests under the same conditions as an actual vehicle are now possible.

FF transmission bench

FF transmission bench


High-speed, low-inertia dynamos (S-DSD,S-DSDi, S-DSD HP,S2-DSD) High RPM/Super low inertia/Small size/Excitation
Output ~505 kW
Rotating speed ~ 10,000 min-1
Torque Up to 1,610 Nm max
Inertia moment (J) 0.016kg・㎡~
Super high speed, low-inertia dynamo (S-DSD HS) Super high rotating speed/Low inertia/Small size
Output ~275 kW *Please consult us for outputs exceeding 220 kW.
Rotating speed ~20,000 min-1 *Please consult us for outputs exceeding 16,000min-1.
Torque Up to 525 Nm* max
Inertia moment (J) 0.169kg・㎡~
High-torque, low-inertia dynamo (H-DSD, W-DSD) High torque/Low inertia/Wide range
Output ~535 kW
Rotating speed ~4,000min-1
Torque Up to 5,960 Nm* max
Inertia moment (J) 0.93kg・㎡~

*Please consult us for torques exceeding the indicated values.

Common specifications
Protection IP42
Insulation type H
Attachment method Leg-mounted standalone (side)
Cooling method Water cooled
Starting torque 150%
Overload capacity 150% for 1 minute
Lubrication method Grease lubricated/Oil-air lubrication
Attachments Speed detector
PTC thermistor