Chapter 2 Product Information
ACH200 Series High Voltage Variable Frequency Speed Control System Operating Manual
13
Figure.2-4
1) Transformer cabinet composition:
The transformer cabinet contains mainly high-voltage isolated phase shifting transformers. In
the case of a 6kV high voltage frequency conversion system, for example, each phase of the power
cabinet consists of five power units. These units are powered by the secondary side of the isolation
phase shifting transformer, and the secondary sides differ by a phase difference in turn, allowing for
multiplexed series rectification. In the primary side of the phase shifting transformer, the current
waveform of each converted secondary side is very close to a sinusoidal waveform after
superposition, so that the harmonic interference to the grid is very low and fully meets the
requirements of various international and domestic standards including IEEE 519-1992 and
GB/T14549-93. At the same time, the power factor of the system is improved.
The transformer cabinet also includes temperature measurement points for the temperature
monitoring controller, which monitors the temperature of the windings in a real-time cycle. The
transformer temperature monitoring controller will promptly feedback information about
transformer over-temperature or transformer faults to the control cabinet, ensuring reliable operation
of the transformer.
2) Power cabinet composition:
The power cabinet is the core part of the main circuit of the AC drive power, it consists of
several identical power units, the output voltage of each power unit is superimposed in series to
form the three-phase voltage output to the motor.
Taking a 6kV high voltage AC drive speed control system as an example, each phase contains
5 power units and the output voltage of each power unit is AC 690V, the phase voltage is 5 x 690V,
i.e. 3450V, and accordingly, its line voltage is 6kV.
