4-quadrant recuperative frequency converter (Active Front End)


QUATROFREM is a family of 4-quadrant VONSCH frequency converters. These converters are often called as Active Front Ends. QUATROFREM converters allow bidirectional power exchange between distribution grid and the motor. Furthermore, in contrast to standard frequency converters the current from the mains grid is of clean, sinusoidal shape, with configurable power factor.

QUATROFREM reduces the biggest “disadvantage” of standard frequency converters – high harmonic current flow from supply network. QUATROFREM practically “gets” just first harmonic of the current, thus meeting the strict standard EN 61000-3-12, which any “classical” frequency converter can not meet.

QUATROFREM ensures the recuperation of the energy to the supply grid during the regenerative operation of the motor. The most advantageous use is in the plants where frquent and energetically massive regenerative operation occurs. Compared to standard frequency converter (which turns the energy created during the regenerative mode of operation to heat of the connected brake resistor), QUATROFREM acts incomparably more economically. Ideal applications for 4-quadrant frequency converter are lifts of the cranes and elevators. Energetic advantages are notable in applications where dissipation of braking energy into braking resistor causes undesired heating of the surroundings. QUATROFREM is also targeted to be used in wind power-plants. It is also convenient to use QUATROFREM in case of request for minimization of THD, even if the energy recuperation does not occur.

QUATROFREM controls the power factor (cos φ) and in comparison to other 4-quadrant converters, it allows the end user to set the desired power factor in the range of (0.95 – 1), which can compensate the capacitive currents flow in the same grid.

QUATROFREM is able to keep its output voltage at nominal value even when input voltage drops by 15%. That keeps the nominal power of the drive during voltage drop or fluctuations and keeps smooth flow of motor torque. At nominal value of input voltage, QUATROFREM can increase output voltage by more than 10%, which ensures the increase of motor power by 10%.


Technical data

Input voltage: 3 x 400 V, + 10%, -15%
Input frequency: 47 - 63 Hz
Degree of protection: IP43 ÷ IP54

The type of the converter M ~ variable load Nominal input current of the converter InIN [A]
Motor output rating Pmot [kW] Nominal output current of the converter Inout [A]
QUATROFREM 400 011 11 24 18
QUATROFREM 400 015 15 33 24
QUATROFREM 400 018 18.5 40 29
QUATROFREM 400 022 22 47 35
QUATROFREM 400 030 30 63 47
QUATROFREM 400 037 37 76 58
QUATROFREM 400 045 45 90 70
QUATROFREM 400 055 55 112 86
QUATROFREM 400 075 75 145 117
QUATROFREM 400 090 90 176 140
QUATROFREM 400 110 110 216 171
QUATROFREM 400 132 132 260 205
QUATROFREM 400 160 160 315 249
QUATROFREM 400 200 200 396 311
If you require a converter of similar type, but out of range shown in the table, please contact our sales department.
Pic. 1.  Input current (measured at nominal load)
Pic. 1. Input current (measured at nominal load)