Our field of activity drive technology offers solutions for new drives, revampings and modernisations

Our know how covers all applications for speed and non-speed controlled drives. We design, deliver and put into operation: 

	Synchronous and asynchronous motors
	DC motors
	Starter units to limit the start up current of large motors
	Converters for DC motors
	Converters and inverters for low voltage and medium voltage motors
	Revamping and modernizing of drives
	Drives and thyristorized equipment with highly dynamic properties
	Drive solutions with special technologies for the steel industry
	Controlled drives for sugar centrifuges
	Drives for conveyor belts
	Drives for pumps and fans
	System solutions for compressors also in explosive atmospheres and flameproof operational conditions.

We are experienced in the saving of energy and give advice in case of revamping or optimization of existing plants.

 

Synchronous and Asynchronous Motors

You can consult us for the supply of all medium and large squirrelcage or slipring motors. They can be supplied for high voltage in the power range between 200 kW and 35 MW. Starters for these motors are available here. The following pictures show products during manufacture.

Flameproof asynchronous motor class EEx p IIA T3	Stator of a main drive	Rotor of a main drive

 

We can supply standard threephase motors with a shaft center height of 56 to 315mm with an output of 0,09 up to 200kW according to EFF2 with high efficiency.

Our program covers the following motors:

• Motors according. to the user's specification

• Threephase motors

• Ship motors acc. to GL

• Motors with CRUS certificate (CSA, UL, NEMA)

• Brake motors

• Single phase motors

 

DC Motors

Our scope of supply ranges from shaft center height 90 to 900 mm, which corresponds to output up to approx. 3000 kW. The D.C. motors are resistant to converter operation and suitable for field suppression and high overloads. For revamping of rolling mills we supply heavy equipment for horizontal and vertical mounting with air and water cooling. For the types please look up the following graph:

 

Other outputs and dimension requirements can be supplied upon inquiry.

 

Starters for synchronous and asynchronous motors

Our program covers three different starter systems for electric motors.

• Electronic soft starter with thyristors up to 4 MVA motor output

• Starting transformers for synchronous an asynchronous motors up to 25 MW

• Liquid starters

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.

 

output range: 100 KW to 12 MW speed range: 0 to 100% execution: air or water 6-, 12- and 24-pulses   DC drive with thyristors, single line and torque/speed range

 

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.

 

This converter drives a DC rolling mill with 5150 kW at a speed of 40/80 rpm with a rated current of 750 Amp The converter for the field supply is fitted into a seperate 600mm cubicle. 

 

Inverter for AC motors in low and medium voltage

We design and offer all necessary inverters for new plants and revampings.

 

  VSI inverters with constant voltage intermediate circuits and diode feeder for 2 quadrant drives (DFE) 

output range:  690V to 3,5 MVA to 2,3 kV: 1,4 to 12 MVA to 3,3 kV: 6 to 22 MVA to 4,2 kV: 6 to 28 MVA to 6,6 kV: to 13,5 MW to 10 kV: on demand speed range: 0 to 100 % cooling: air or water

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.

Diagram for inverter free of line reactions	Current and voltage sine wave  free of line reaction at the point of supply

 

690V VSI with Active Front End

 

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. 

output range up to 690 V: 100 KVA to 4 MVA to 2,3 kV: 1,4 to 12 MVA to 3,3 kV: 6 to 22 MVA to 4,2 kV: 6 to 28 MVA speed range: 100% to 100 % cooling: air or water

 

	VSI invertors with constant voltage intermediate circuits with IGBT feeders (AFE) and energy interchange across the DC bus for four controlled motors

 

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.

output range: approx.1 to 50 MW speed range: up to max 6000 rpm cooling: air or water

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:

• Revamping of inverters for speed controls of pumps and fans for economizing energy and reduction of losses in power stations and other industrial plants

• Modernizing of DC drives in steel plants or mines

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.

In case of modernization of thyristor equipment sometimes it is useful to retain the old thyristor power modules. We can supply in such cases a new digital control with an interface made to order which suits the given situation of the power module. The new control can be fitted to usual bus systems (Profibus-DP, CAN) in order to communicate with the corresponding automation level. The control electronic has a drive structure which may be flexibly combinable with a number of technological control units, automatic control circuits or failure memories. If new power modules are required, we are prepared to offer them.

An inquiring checklist for your modernizing intentions may be requested by email. The questionnaires are available in German, English, Russian or Spanish. 

 

Drives and thyristorized equipment with highly dynamic properties

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.

 

Characteristics: Output range 10 to 4000kW Feeder 400 to 690V  Line frequency  50 or 60 cycles Line re-feeder by pulses Torque control reaction time < 1,5ms speed control range with tacometer 1:1000 High synchronism at low Field control > 1:5 Refrigeration by air or water Protection type IP23 und IP54 EMV acc. to IEC 801-2...4
Other applications upon request	Diagram of torque and intermediate circuit voltage after an increment of the reference value of  -50% to +100%

Drive solutions with special technologies for the steel industry

Scheme of the input into a processing line

IGBT inverter with DC bus, four motor controls and a line control

Controlled drives for sugar centrifuges

We supply motors and inverters with automatic controls and control panels

Speed controlled non-continuous sugar centrifuge plants

Diagram of a centrifuge control

Drives for conveyor belts

The advantages of a conveyor belt with speed control::

• Instead of slipring motors, squirrel cage motors should be used

• The resistance controller in the rotor circuit may be omitted

• A complete reserve drive for revision purposes can be omitted

• A lower, more economic belt configuration can be selected

• The losses are considerably lower

• The maintenance cost can be reduced, lesser failure and breakdown times 

• Roller, belt and gear are subject to lower wear rate

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).

An essay on the above mentioned plant with three phase squirrel cage motors regulated by speed controlled inverters is available as pdf (450k).

Drives for pumps and fans

 

Control of a water pump over a throttle valve with a high loss range	Speed controlled pump with optimum efficiency

 

 

Energy consumption of three control systems across the liquid output Q

 

Power station auxiliary drives

Evidence of the advantage of a speed control: During the months 3 and 12 the steam production was equal, the current consumption however four times as high 

System solutions for electronically controlled compressors

Piston compressor with a speed controlled motor of an underground gas deposit