Thirteen‐level cascaded H ‐bridge inverter operated by Generic phase shifted pulse‐width modulation

Abstract

The study proposes a new Generic phase shifted (PS) pulse-width modulation (PWM) approach. Four Generic PS PWM algorithms are proposed. The important advantage of the proposed approach is that it can be easily implemented with multilevel inverters of any topology. The first method produces the 13-level PS PWM signal from six 3-level phase disposition (PD) PWM signals whose carrier signals are PS from each other by the time interval of 1/(6f carrier). The second method produces the 13-level PWM signal also from six 3-level PD PWM signals, whereas their modulation and the carrier signals are both PS by the time interval of T modulation /(6 × 5), where T modulation is the modulation cycle time interval. The third method produces the 13-level PWM signal from three 5-level PD PWM signals, whereas their carrier signals are PS from each other by the time interval of 1/(3f carrier). The fourth method produces the 13-level PS PWM signal from three 5-level PD PWM signals, whereas their modulation and carrier signals are both PS by the time interval of T modulation /(3 × 5). The proposed methods are analysed and compared one to the other and to the conventional PD PWM method. The analysis is validated by extensive simulation results.

Cascaded H-bridge multilevel inverter for renewable energy generation

“…As a compensator the role of CHBMLI based renewable energy system is to reduce the reactive power supplied by the grid and harmonics injected by load up to its capacity to improve the operating power factor of the grid. Grid integrated renewable energy source analysed for linear load of 25 KVA at 0.8 pf and diode rectifier load of (10+7.45)Ω under compensation mode is assumed for performance evaluation of the system.The Control block in Fig.8 is responsible for synchronization of power generated from renewable system and grid using Phase locked loop(PLL) and multilevel inverter comprises of additional switching devices in comparison to conventional inverter.So sinusoidal pulse width modulation(SPWM) used for conventional inverter is extended for switching of multilevel inverter [15].In this paper PSPWM (Phase shift pulse width modulation) is used to control the multilevel inverter requires hierarchal switching scheme [16].For compensator reference current generation, algorithms like synchronous reference frame theory (SRFT), power balance theory, Instantaneous Power theory is introduced in [17].In this paper the SRFT based control is implemented for generation of reference current . The result shown in Fig.9 shows the impact of compensator to the grid current and voltage while load is not ideal (low p.f.…”

A Modulation Scheme for Floating Source Multilevel Inverter Topology with Increased Number of Output Levels

“…Multilevel inverters are divided into three main types: neutral-point clamped or diode-clamped (NPC) [7], [8], flying capacitor (FC) [9], [10] and cascaded H-bridge inverters [11]- [13]. These multilevel inverters are controlled by several techniques, as in [14], where the most common technique is multicarrier sinusoidal pulse width modulation (SPWM) [15] and [16]. As the number of levels in the multilevel inverter output increases, the wave is near sinusoidal shape with less harmonics.…”

UPSC SVPWM controlled multi‐level inverter topology for multiple pole‐pair induction motor drive for minimising torque ripple

“…harmonics at first, second and third centre band can be cancelled) by using unipolar phase shifted carrier (UPSC) PWM technique. In this PWM technique, harmonic cancellation can be achieved by providing appropriate phase shift between the modulating waves and carries waves as presented in [12][13][14][15]. In order to use this PWM technique, more number of load terminals (generally two terminals per phase are available) are required and each terminal should be connected to a two-level inverter.…”