Electric drive solutions

Frequency converters have already been an integral part of the industry for many years, as they provide a very effective and reliable way to control the AC motors. VONSCH manufactures frequency converters in the range from 0.37 kW to 1400 kW. In the case of requirement of higher power frequency converter, please contact us at sales@vonsch.sk .
Standard range frequency converters:

• UNIFREM - the flagship of VONSCH, versatile, modern coverters built with the best elements, having rich software features. They are available in the following options:
  • UNIFREM 400 ... M - small converters with voltage 3 x 400 V for 400 V motors with power range 1 1 - 11 kW.
  • UNIFREM 400 - converters with power 3 x 400 V for 400 V motors with power range from 11 to 630 kW.
  • UNIFREM 500 - converters with power 3 x 400 V for 500 V motors with power range from 15 to 200 kW.
  • UNIFREM 690 - converters with power 3 x 690 V for 690 V motors with power range from 315 to 1400 kW.
• UNIFREM 230E - small, simple converters for 230 V motors in power range between 0.55 - 1.5k W
• UNIFREM 400E - small, simple converters for 400 V motors in power range between 0.75 - 3 kW
• VQFREM - the previous generation of frequency converters VONSCH, their production is discontinued.

Regenerative drives QUATROFREM , also known as Active Front End are also built on the popular UNIFREM platform. Despite the regular frequency converters, recuperative converters are equipped with controlled rectifier allowing bidirectional power flow.

Benefits of Active Front End:

• The possibility of supplying energy to the grid, not just consumption
• Energy produced in the regenerative mode of operation is supplied to the grid - there is no need of burning the excess energy in the braking resistor
• The current on the grid side is of a pure sine wave shape, with the current THD lower than 3%

Disadvantages:

• Higher cost

Its main advantage is in the applications, where there is a very frequent or even permanent regenerative mode of operation, where regenerated energy leads to rapid returnability of the equipment. This can be lifts, cranes, some strokes, or in general applications with speed control of induction or synchronous generators. Further opportunities are facilities with very strict requirements for current harmonic distortion like laboratories or residential zones.

Soft starter is a device for soft start of line connected motor to nominal speed as well as the soft stop of motors with low-inertia when there is a requirement of some torque during stopping - eg. coasting pumps with a check valve. The principle of soft starters is in continuous change of voltage (phase control) during acceleration (deceleration), thus limiting the current, but at a price of decreasing the motor torque. Therefore softstarters are not suitable for start up of large inertia loads and obviously not suitable for variable speed control as are the converters.
VONSCH produces soft starters SINAM 400 for 400 V motors in the range of 4-630 kW. If required, we also supply 500 Volt SINAM 500 or 690 Volt SINAM 690 version.

If you require converters out of our standard range or need a converter features which you can not find in the market, we are ready to face your challenges! We specialize on customized solutions of electric drives since founding of the company. We address the traction locomotives, special machines, residential and industrial lifts and we succeeded in many applications where our competitors could not make it.
If you have any requests or questions, please contact our sales department .

For the purposes of choosing the right product for your drive, we have made a Product selection guide . It is a web application that lets you enter information about the motor, and its result is the right VONSCH product.

Pumps are a typical application for AC drives, we deploy our frequency converters for pump control since the very beginning of their production in the company VONSCH. Currently we recommend pump control using frequency converters UNIFREM precisely UNIFREM 400, UNIFREM 500 and UNIFREM 690.

Features of UNIFREM suitable for pump control:

• The current limit is used to limit current for reliable and efficient management of motor pumps
• Nonlinear V/f characteristic curve or the possibility of open-loop vector control for minimizing the input power
• Very good short-term overload and overall robustness of the converters

Industrial fans are among the most common applications for AC drives, we deploy frequency converters for fans since the very beginning of their production in the company VONSCH. Currently we recommend control of motors for fans using frequency coverters UNIFREM and UNIFREM 400, UNIFREM 500 and UNIFREM 690.

Features of UNIFREM suitable for fan control:

• The current limit is used to limit current for reliable and efficient management of fan motors
• Nonlinear V / f characteristic curve or the possibility of open-loop vector control for minimizing the energy input power
• Flying start
• Very good short-term overload and overall robustness and resistance converters

VONSCH has many years of rich experience in the regulation of crane drives, whether the travel, crab or lift. Currently we recommend to address the control of crane drives using frequency coverters UNIFREM - UNIFREM 400, UNIFREM 500 and UNIFREM 690.

The following features of UNIFREM converters suitable for crane drives:

• Adjustable S-curve allows smooth acceleration and deceleration of the travel and crab, reduces swinging of the load
• Advanced vector control, its deployment reduces the drive current, while reducing wear on brake linings
• Special crane functions:
  • Built interaction with mechanical brake, advance, delay, brake frequency
  • 4 multi-purpose, programmable limit switches, function: slow down, stop, track and stop and other
  • Built-function Overload Protection Switch defines the maximum current, torque or any other variable, after exceeding of which the lift is not permitted, just lay down of the load.

The solutions of traction inverters is a field where VONSCH has years of experience, particularly in the field of control and regulation of induction motors. In recent years, ww and our partners, engineering companies, have developed various types of mining electric locomotives, which are successfully deployed in mines in Poland, Czech Republic, Turkey, Russia and other countries.

Do you want to work with us on an electric drive for your device? If so, please feel free to contact us . And see the presentation of our solutions of traction drives.

Based on the market requirements for frequency converters for high-speed motor drives of cutters, grinders, spindles, we have developed high-frequency converters UNIFREM VF . This is a special hardware and software modification of UNIFREM frequency converters, enabling the output frequency up to 3000 Hz, with the PWM switching frequency to 20 kHz.

If you have any comments, questions or requirements, please contact our sales department .

There are a number of servo drives used in industry with various functions made by different manufacturers. It is quite common that our customers are asking us about a possibility of replacing the existing servo system with induction or synchronous motor. And thanks to the rich list of features of new software UNIFREM drives and its peripherals, it is often possible. If you need to design and implement a servo system with our converter for your machine, We are able to help you with this task, from the beginning of the development to the successful completion of functional tests of the machine.