Starters for synchronous and asynchronous motors
Our program covers three different starter systems for electric motors.
Our electronic soft starter protects your motors and the driven machine by way of a soft acceleration control. It avoids the typical starting problems like high currents and high wear and tear. These products are available for line voltages of 400, 500 and 690V up to 3000A. The soft starters are mounted into the motor feeders. Typical applications are all non speed-controlled drives as conveyors, compressors, coolers and mixers, fans, mills, pumps and centrifuges.
The starting devices with starting transformers for medium voltages up to 13,8 kV are designed according to the three breaker method of Korndorfer. The supply covers a complete unit with transformer, vacuum breakers (star point and bridging contactors) plus protections.
Single line for starting transformers
Our starters will be supplied independently from the manufacturers of motor and switchgear. They can be mounted directly next to the motor or in a switch cabinet. The transformers can be supplied optionally with oil cooling or as dry type. For the dimensioning we need a speed / torque curve, motor starting current at direct on line operation and the WD2 values of the drive. If desired, we can dimension economic liquid starters for your plant.
Converters for DC motors
We supply digitally
controlled CD converters for drives in one- and four quadrant
operation, for other supply and filed excitation control with
constant output in this range if desired. The field weakening
reduces the torque with increased speed.
This classic DC drive technique is frequently still in use. It is applied often in modernizing and revamping jobs in the steel industry. In case AEG products like Minisemi, Midisemi and Maxisemi cannot be supplied any more, we can offer suitable substitutes. The following picture shows a switch cubicle of a large rotor converter of 750V DC and 14000 Amps DC in 24-pulse execution.
Inverter for AC motors in low and medium voltage
We design and offer all necessary inverters for new plants and revampings.
VSI invertors for 2-quadrant drives (DFE):
In case AEG products like Monoverter, Semiverter, Multiverter and BL Motor cannot be supplied any more, we can offer suitable substitutes.
VSI invertors with constant voltage intermediate circuits with IGBT feeders for 4- quadrant (AFE) drives without line reactions:
For multimotor drives a VSI invertor can be equipped with various motor inverters and a controlled DC bus provided. From the supplying grid only the total of active power is drawn in this case. In plants frequently only some motors are operating motorically, others are feeders. The feeding drives (which are braking) across the DC bus are supplying energy to the driving motors. This is an optimal energy concept.
BL-Motor- Inverter with constant current intermediate circuits for synchronous motors
The BL-drive is specially suitable for large driven units with only one direction, e.g. pumps, fans and compressors. It is also in use as starting inverter in power stations.
Further information on the BL drive system is available as pdf-document.
Modernizing and backfitting
We avail of special experience in modernizing drives in the following fields:
The following picture shows the mounting of a water cooled inverter in a container cubicle and its installation in a machine hall of a power station in Italy. It was an order for four feed water pumps with 2,1 MW each in a container of 5 by 3 by 3 meters with a complete inverter and insulated direct water cooling for each drive.
We will modernize not only AEG
thyristorised equipment, but also existing products of other makers
from east or west Europe and include usable parts into new
solutions. There is often considerable economic interest in
modernizing old DC drives of medium or large output. It is often the
case in in rolling mills, cement plants, mine hoists and cranes. The
new, fully digital information technology may also be used for
drives of high dynamic requirements. Existing DC motors will be
inspected in case of need and refurbished. Our suppliers can provide
for new motors if required.
Especially for test benches of the automobile industry we can offer suitable speed controlled drives. Our offer includes the semiconductor equipment, motors with rotors of low rotating masses and intelligent interfaces for primary automation modules. We avail of considerable experience with motor and gearbox test benches as well as car test benches and for other related uses.
Drives for conveyor belts
The advantages of a conveyor belt with speed control:
If existing conveyor belts are equipped with speed controls and the slipring motor shall be retained, we can offer an electronic speed control with a subsynchronous thyristorized cascade (USK).
essay on the above mentioned plant
with three phase squirrel cage motors regulated by speed controlled
inverters is available as pdf.