77855 Achern-Gamshurst
Oststrasse 17 Germany
Tel. : (49) 78 41 / 20 52- 0
No.
70.IT1686.4 E
Fax : (49) 78 41 / 20 52-52
Rev. A
Page 3/3
General Description
Inverter
The figure beside shows the connection of a switchmode inverter and a transformer.
The figure below shows the circuit of the inverter:
The intermediate circuit voltage (DC-input voltage) is transformed by the power transistors T1-T4
with the parallel inverse diodes D1-D4 in a pulse-width square-wave voltage. The choke with the
windings LI and LII integrates this voltage, and at the capacitor C there is a sinusoidal output voltage.
The power transistors are controlled by opto-coupler, making sure, that not both transistors of one
branch are switched on at the same time by the control pulses. The output voltage is connected via
sense leads to the control circuit and controls after a comparison with a reference the control pulses
for the power transistors.
The output signal of the current transducer is also supplied to the control circuit and serves for current
limiting.
Alternating voltage at the output of the inverter is transformed by means of a transformer to the
requested output voltage with galvanical isolation.
Summary of Contents for IT 1686.4
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