Frequency inverter for controlling any main equipment could be included to composition of switchgears 6 (10)kV performed according to the technical information KSPE.140.001-13

There is a polyphase input power transformer in a frequency inverter, this is minimize exposure to an electricity network (not more than 5% of the level of generated noise in the network), at that cos φ > 0.96. Usage the cascade circuit of generation of output voltage, based on power IGBT modules and a digital control, this eliminates output filters, because the shape of the output voltage is close to the sine wave, the value of dU/dt is small. That is why frequency inverters are applicable with a system of long output cables without the threat of damage or motor windings insulations. Total efficiency is more than 96,5% (taking into loss in an input transformer and additional devices) and more than 98% for the inverter’s part.

The function of automatic regulation of output voltage is realized in frequency inverters, this allows to maintain voltage at a constant level when input voltage fluctuations within ± 10% of U n , thereby providing a stable and safety engine work.

Frequency inverters have a high-level security at the expense of next technical decisions:

1. Power components are used in the middle of the currying capacity range for them.
2. The cooling and temperature control systems provide optimal work for each elements of the device.
3. Special cover of power bus lines decrease parasitic inductance and pulse surge in IGBT modules.
4. There are extended life capacitors in DC circuit.

ПFrequency inverters could be equipped by the function of engine switching from output to input inverter and back (synchronization with the electricity network).

Built-in function of diagnostics alarms users to trouble in the power part, the cooling system and need for its services.

User-friendly interface makes controlling easier; it is professionally tuned to the requirements of a specific application.

Schematic structure of the frequency inverter is shown on the top.