• Kimo Industrie-Elektronik GmbH

Frequency Inverter

Kimo Industrie-Elektronik GmbH offers Frequency Inverter for speed control (open and closed loop) of three-phase motors up to powers of 30 kW.

TRANSOMIK U1 Frequency Inverters are suitable for the starting, braking, speed variation, closed-loop control and positioning of three-phase induction motors.

TRANSOMIK U1 Frequency Inverters belong to the type of inverters with a constant DC link voltage and an inverter with pulse width modulation.

A rectifier supplies the DC link. A three-phase bridge connection of IGBT transistors converts the DC voltage into a three-phase voltage supply of variable frequency and voltage.

The self optimizing pulse width modulation (PWM) makes use of voltage feedback in each output phase. The switching frequency is not fixed, but statistically spread over a wide range. Therefore the motor noise is very low.

Two adjustable speeds are provided for with TRANSOMIK U1. The lower speed N1 is intended for minimum speed or for commissioning or positioning, the upper speed N2 for normal operation. The speed can be varied between these limits using an external potentiometer or with an external voltage/current source.

During braking the frequency and voltage are reduced in accordance with the set deceleration. If the load has a high kinetic energy and is braked severely, the DC link voltage can reach the operating limit. The inverter bridge then switches to the mode "Low frequency braking" until the motor speed has fallen to N1.

A braking chopper is not necessary for simple applications, but is recommended for ambitious applications requiring repetitive dynamic operation.