| Abstract |
Use of multilevel converters has become popular the recent years for high power applications [1].
Numerous topologies have been introduced and investigated for utility and drive applications. For
drive applications, the most popular topology seems to be the diode clamped topology introduced in
[2].
When designing a converter it is useful to have analytically formulas to calculate electrical stresses in
the switching devices at different loading. This paper is presenting analytical expressions for the
power losses in the switching devices in 4- and 5-level diode clamped converters.
The equations derived in this paper are based on a method presented in [3] and [4]. It is a method to
calculate the discontinuous currents in Pulse Width Modulated (PWM) converters with high switching
frequency. The method transforms discontinuous currents or voltages to continuous, which are almost
similar with respect to power losses.
By using analytical expressions, time consuming time domain simulations are avoided. At last a
comparison of the switching and conduction losses between 2-, 3-, 4- and 5-level is done. |
