Space vector pulse‐width modulation for single‐phase full‐bridge Z‐source inverter

This paper presents a hysteresis current control technique with shoot-through states distribution. This control algorithm could be applied to three-level and multi-level inverters with any impedance source network where reference current control signal along with shoot-through states are required. Possible modifications of the presented algorithm are discussed. The steady-state analysis was made to explain the operation principle of the algorithm. As a result, the link between the band ratio of the hysteresis current controller, the input voltage, and the desired DC-link voltage was obtained. All theoretical predictions were proved by simulation and experimental results. Future applications are discussed.Hysteresis current control, which is based on the current reference signal, is often used in traditional CSI and voltage source inverter solutions [32][33][34][35][36][37]. In addition, several approaches for multilevel converters are described in [38,39]. Commonly, hysteresis control is preferable because of simplicity, fast deadbeat transient response, and overcurrent protection. But it is difficult to implement it in the system with shoot-through states.This paper proposes a novel hysteresis current control for a single-phase inverter based on any IS network with distributed shoot-through states. Section 2 explains the novel algorithm in detail. The steady-state analysis is presented in Section 3. Section 4 describes the simulation along with experimental results. Finally, conclusions are presented in Section 5. This paper is based on earlier preliminary publication [40] and includes a comprehensive theoretical analysis and experimental results; however, it is not presented there.

Section: Modified Hysteresis Control Methodsmentioning

confidence: 99%

Hysteresis current control with distributed shoot‐through states for impedance source inverters

Husev

Chub

Romero‐Cadaval

et al. 2015

“…We can assume that ΔV CZTcmax /V CZavTm in one switching period is, eg, 0.03, and subsequently calculate C Zmin . A previous study showed that the output voltage of the inverter with the impedance network is "skewed" ( Figure 5A, "Distortion 1"), 20 but how to improve it was not explained. The reason for this skewness is the 2f m harmonic of the i IIN inverter bridge input current flows during the "non-shoot-through" time ( Figure 5A,B).…”

Section: Z-source and Qz-source Designs To Reduce Static Drawbackmentioning

confidence: 99%

Drawbacks of impedance networks

Rymarski

Bernacki

2017

Summary This paper presents the influence of voltage‐fed impedance networks, known as Z‐source and quasi–Z‐source, as well as some more sophisticated networks on the static and dynamic properties of voltage source inverters. The impedance networks increase output voltage distortions with the second harmonic of the fundamental harmonic and decrease the power efficiency. The distortions of the output voltage increase for the discontinuous current mode of the impedance network. The DC voltage boost factor depends on the impedance network power losses. The impedance networks add 2 resonant frequencies that are very close each other to the control transfer function of the inverter in the frequency range that is close to the fundamental frequency. The influence of the impedance network on the control transfer function depends on the effective damping resistance in the impedance network. The impedance network operation during the “shoot‐through” time increases the damping of the inverter output filter. The effective damping resistances and the inductance of the coils depend on the power losses in the magnetic materials. Theoretical models along with experimental verification can help to estimate the real influence of impedance networks on the inverter properties.

“…The second is the improvement in modeling and modulation control methods to achieve higher performance, reliability and efficiency, or more usable shoot-through range to reach a greater boost ratio. On the other hand, the space-vector PWM control has been modified to be suitable for the qZSI [36][37][38][39][40] owing to the advantages of low current harmonics and high voltage utilization. Then, a 2-stage control method for both output voltage control and current control modes, based on the dynamical model, has been proved.…”

Section: Introductionmentioning

confidence: 99%

A novel modulation technique with interleaved‐and‐shifted shoot‐through state placement for quasi‐Z‐source inverters

Wang

Liu

Cheng

2017

In this paper, a single-phase quasi-Z-source (qZS) inverter (qZSI), integrating the pulse width modulation (PWM) control with interleaved-and-shifted shoot-through state (STS) placement modulation technique, is proposed to simultaneously achieve both dc voltage boost and dc-ac inversion. Instead of placing the STS in both inverter legs simultaneously, the addressed method inserts the STS only in left/right inverter leg separately during the positive/negative half cycle of the output voltage to reduce switching losses and thermal stresses of the power devices. The STS shift is also studied to decrease the switching numbers of power devices and thus can improve the efficiency further. Theoretical analysis and design guidelines of the studied inverter are included. Improvement in effectiveness and performance of the devised scheme and modulation strategy are proved experimentally and compared with the previous studies on a built laboratory prototype. KEYWORDS photovoltaic generation system (PGS), pulse width modulation (PWM), quasi-Z-source inverter (qZSI), shoot-through state (STS)