Single-stage Current Source Inverter Research Articles

Novel Single-Stage Current Source Inverter: Extension to Low-Speed Region in Motor Drive Applications

Novel Single-Stage Current Source Inverter: Extension to Low-Speed Region in Motor Drive Applications

A Single-Phase Single-Stage Current Source Inverter With Buck-Boost Capability and Reduced Inductor

A Single-Phase Single-Stage Current Source Inverter With Buck-Boost Capability and Reduced Inductor

DC Current Control for a Single-Stage Current Source Inverter in Motor Drive Application

The current source inverter (CSI) is a power electronics topology that allows for the realization of variable speed drives (VSD). Compared to the most common voltage source inverter (VSI), which can be directly connected to a voltage source, the CSI needs a prestage to generate a constant current bus. This article therefore seeks to challenge this “accepted” consideration that a CSI always needs this precircuit and seeks to remove this circuit by proposing an innovative i <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dc</sub> current control scheme. The proposed scheme is applied to a single stage motor drive driven by a CSI converter. It is shown how implementing this control scheme removes the need for the front-end stage, thus removing an unnecessary converter and optimizing the efficiency at the same time. The CSI state-space equations are presented and the developed models are verified using simulations. Stability analysis of small-signal model is considered through Nyquist criterion with the robustness in presence of variations of the most important system parameters. Experimental results driving a permanent magnet synchronous machine (PMSM) are shown confirming the validity of the proposed control, potentially paving the way to a larger adoption of the CSI topologies for motor drive applications.

Direct Power Control of a Single Stage Current Source Inverter Grid-Tied PV System

In this paper, a direct power predictive controller (DPPC) is derived for a current source inverter (CSI) based single stage photovoltaic (PV) system. The equations of the dynamics, including AC and DC filters, are formulated directly for the PV power and for the active and reactive power injected in the grid. Then, the prediction equations are synthesized straight for the power, and, at each time instant, the optimal switching vector that guarantees simultaneously the control of the power generated by the PV arrays, and the control of the reactive power in the connection to the grid is chosen. This approach aims to guarantee fast and accurate tracking of the power. The proposed system is then validated through simulation and experimental results, showing that the PV system is able to follow the power references, guaranteeing a fast response to a step in the power, and decoupled active and reactive power control, with minimum total harmonic distortion (&lt;5%) of the currents injected in the grid.

Current source inverter‐based photovoltaic system with enhanced active filtering functionalities

This study proposes a three-phase photovoltaic (PV) inverter, with active power filtering capability that allows for maximum power point tracking (MPPT) and a nearly unitary power factor (PF) in the connection to the low voltage grid. A single-stage current source inverter, with an inductive DC link, connects the PV array to the three-phase grid for reduced cost and improved performances, and the MPPT algorithm controls directly the power of the PV array. On the basis of the power balance of the whole system, the grid current references are generated in a grid-synchronised dq frame allowing for the mitigation of low-frequency current harmonics introduced by a non-linear load connected at the point of common coupling, without the need for additional measurements. Active damping is used to minimise filter losses and reduce the high-frequency harmonics that result from the semiconductors switching. Simulation and experimental results are presented in unloaded and loaded situations, and with varying irradiance, to confirm the active filtering, PF regulation and MPPT operate correctly.

Dual Transformerless Single-Stage Current Source Inverter With Energy Management Control Strategy

Alternative energy sources have for some time attracted great interest in the area of static converter development. This fact is related in greater part to issues such as sustainability and detrimental effects on the natural environment, which all contribute to the viability of this type of energy source. In this context, power electronics performs important tasks making viable the connection of all these kind of clean power sources to the conventional grid and also to the load. From this perspective, a new challenge must be faced which is the development of energy management systems capable of providing intelligent planning and control of appliances in low- and high-power applications. That being so, this paper intends to contribute presenting a novel dual transformerless single-stage current source inverter fed by a proton exchange membrane fuel cell (PEMFC) and a photovoltaic (PV) array. High voltage gain and totally controlled output voltage can be achieved without using dedicated step-up dc-dc converters or transformers either. The main feature of this inverter structure is the intelligent power management technique which focuses on the extraction of maximum power from the PV array keeping the PEMFC as an energy storage system. Theoretical analysis is presented and corroborated by experimental results of a 400 W laboratory prototype.

Evaluation of a single-stage current source inverter with high-voltage gain supplied by a polymer electrolyte membrane fuel cell

Alternative energy sources have for some time attracted great interest in the area of static converter development. This fact is related in greater part to issues such as sustainability and detrimental effects on the natural environment, which all contribute to the viability of this type of energy source. The principal challenge therefore becomes the development of systems that transform the produced DC current into AC current. The authors of this study have therefore focused their efforts upon the establishment of a new control strategy applied to a step-down/step-up single-stage inverter with imposed waveforms of input current and output voltage. The proposed control strategy provides high-voltage gain without the use of a high-frequency transformer, which contributes to weight and size reduction in the proposed DC-AC converter structure. A theoretical analysis is presented and corroborated through the experimental results of a 400 W laboratory prototype fed by a polymer electrolyte membrane fuel cell.

Single-stage Current Source Inverter With Amplified Sinusoidal Output Voltage: Analysis, Simulation and Experimental Results

Alternative energy sources has been attracting great interest in the area of static converter development. This fact is related to issues like sustainability and the world environment, which is contributing to viability of this type of energy source. The main challenge is to develop systems that transform this DC energy in AC. Within this subject, this paper focuses the establishment of a new control strategy applied to a step-down/step-up single-stage inverter with imposed waveforms of input inductor current and output voltage. The proposed control strategy provides high voltage gain without using high frequency transformer, which contributes to weigh and size reduction of the proposed DC-AC converter structure. Theoretical analysis are presented and corroborated by experimental results of a 180W laboratory prototype.