Optimized Modeling and Control Strategy of the Single-Phase Photovoltaic Grid-Connected Cascaded H-bridge Multilevel Inverter

Abstract

This paper presents the modeling and control-loop design method with an inverted decoupling scheme of a single-phase photovoltaic grid-connected five-level cascaded H-bridge multilevel inverter. For the unity power factor, the proportional and integral current controller with a duty ratio feed-forward compensation is used. In addition, in order to achieve the maximum power point tracking of each photovoltaic array, when the stacked modules are in the partial shading condition, each direct current (DC) voltage is stably controlled to their maximum power points (MPP) by dedicated voltage controllers of each H-bridge module. This paper also presents a control method that minimizes the effect of the loop-interaction in the design of an individual DC-link voltage control loop in a two-input two-output system. The proposed control methods of the cascaded H-bridge multilevel inverter are validated through the simulation and experimental results of the 2-kW prototype hardware.

Analisis Simulasi Inverter Multilevel Kaskade dengan Teknik Selective Harmonic Elimination Pulse Width Modulation

“…Berbagai penelitian juga telah dilakukan untuk meningkatkan kinerja inverter multilevel, antara lain: a) eliminasi harmonisa menggunakan prakalkulasi fungsifungsi pensaklaran [9], b) mengembangkan topologitopologi inverter multilevel [10], [11] dan c) memperbaharui strategi kendali [12]. Penelitian lainnya [13]- [15], melaporkan bahwa inverter-inverter multilevel yang sudah dikembangkan berhasil beroperasi pada frekwensi rendah.…”

Four-Level Quasi-Nested Inverter Topology for Single-Phase Applications

“…The main advantages of MLIs are waveforms with lower harmonic content and less total harmonic distortion (THD), which makes possible a reduction of filter sizes, as well as reduced stress due to voltage rate of change (dv/dt) and electromagnetic interference [13]. A relevant application of single-phase inverters is the transformerless integration of photo-voltaic (PV) power generation systems [14,15], where MLI topologies have been proposed recently [16][17][18][19][20]. Other applications of single-phase MLIs can be found in active power filters [21] and electric motor drives [22,23].…”

Dual 3-Phase Bridge Multilevel Inverters for AC Drives with Voltage Sag Ride-through Capability

“…Multilevel topologies present several advantages over the 3-phase two-level inverter [26]. Several multilevel topologies have been proposed to be used in AC VSDs, being the most known and studied flying capacitor-based inverter, including the Neutral-Point-Clamped (NPC) and the cascaded H-bridge inverter [27][28][29]. The third solution has the advantage of using simple single-phase two level VSIs.…”