10.46243/jstj.2017.v2.i4.160 registered

In phased-shifted modulation, a multilevel inverter converters use resonant sub-modules to achieve high power with m voltage levels requires (m – 1) triangular carriers. In the conversion and efficiency [14], but the main disadvantage is phase-shifted multicarrier modulation, all the triangular carriers the requirement of a large number of isolation transformers, have the same frequency and the same peak-to-peak amplitude, which have high potential differences between the windings. but there is a phase shift between any two adjacent carrier waves, Switched capacitor converters with series-parallel topologies given by Ɵcr = 360°/(m – 1). In the case of a 7-level CHB (m = 7), are subject to incremental voltage stress either on the module as we used in our project, all carrier waves (7-1 = 6) are 60o apart from the neighboring carrier waves. Similar to the phaseswitch or on the module capacitor. The highest voltage stress shifted modulation, an m-level CHB inverter using level shifted is close to the output (high-side) dc voltage. The switched multicarrier modulation scheme requires (m – 1) triangular capacitor converters are also subject to high charge losses and carriers, all having the same frequency and amplitude. The (m – overshoot currents. This problem can be mitigated by driving 1) triangular carriers are vertically displaced such that the bands MOSFETs with very high switching frequency. Therefore, they occupy are contiguous. The frequency modulation index is switched capacitor converters are only used under low voltage given by mf = fcr/fm. In the case of a 7-level CHB (m = 7), as we condition. A power electronics based Cockcroft-Walton used in our project, all carrier waves (7-1 = 6) are displaced from multiplier has been demonstrated in [15]. This is a light and the neighbouring carrier waves. cheap solution for high voltage dc experiments when only unidirectional step-up conversion is required. A bidirectional