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New regulations impose more stringent limits on current harmonics injected by power converters that are achieved with pulsewidth-modulated (PWM) rectifiers. In addition, several applications demand the capability of power regeneration to the power supply. This paper presents the state of the art in the field of regenerative rectifiers with reduced input(More)
This paper is related to faults that can appear in multilevel (ML) inverters, which have a high number of components. This is a subject of increasing importance in high-power inverters. First, methods to identify a fault are classified and briefly described for each topology. In addition, a number of strategies and hardware modifications that allow for(More)
Multilevel converters use a large amount of semiconductors, allowing the reconfigurate of the converter to work even on internal fault condition. This paper presents a method to detect faulty cells in a cascaded multicell converter requiring just one voltage measurement per output phase. The method is based on high-frequency harmonic analysis, using a(More)
This paper presents the different technologies used in the generation of large controlled currents, in the kiloamperes range. After a brief review of processes requiring large currents, the paper discusses the working principles of thyristor phase-controlled rectifiers commonly used in these applications. Chopper–rectifiers using high-current insulated gate(More)
Multilevel converters and, in particular, flying capacitor (FC) converters are an attractive alternative for medium-voltage applications. FC converters do not need complex transformers to obtain the dc-link voltage and also present good robustness properties, when operating under internal fault conditions. Unfortunately, with standard modulation strategies,(More)
This paper presents a method for operating cascaded multilevel inverters when one or more power cells are damaged. The method is based on the use of additional switches in the power circuit to bypass the faulty cell. To control the cells, the angle of phase shifting in the carrier signals is modified according to the number of operating cells, to minimize(More)
This paper presents a multilevel converter with regeneration capability. The converter uses several power cells connected in series, each working with reduced voltage and with an active front end at the line side. This paper presents the following: 1) the control method of each cell; 2) the use of phase-shifting techniques to reduce the current and voltage(More)
Multilevel converters are an interesting alternative for high power drives, due to their good quality output signals. Despite their advantages, the large number of components required increases the fault probability. Among the multilevel topologies, the cascade multicell converter presents advantages when operating under internal fault conditions, due to(More)
Multilevel converters offer advantages in terms of the output waveform quality due to the increased number of levels used in the output voltage modulation. This advantage is particularly true for cascaded H-bridge converters that can be built to produce a large number of levels thanks to their modular structure. Nevertheless, this advantage comes at the(More)