The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
This paper describes a detailed operation analysis, proposed dc side control strategy, and implementation of the BQ-ZSI (bidirectional quasi-Z-source inverter) for electric vehicle applications. The power flow can be bidirectional by connecting an active switch antiparallel with the diode in BQ-ZSI. The performance of the inverter under load variation can be improved by inserting an inner current...
The microgrid must be able to transfer from grid-connected mode into islanding operation mode seamlessly to guarantee the power reliability for the critical local load. In the grid-tied mode, the power exchanged with the main grid should be smoothed to reduce the disturbance to the main grid, while the quality of the bus voltage in the islanding operation mode is significant. This paper presents a...
This paper presents design and implementation of a 20 kVA division-summation (D-Σ) digital controlled three-phase four-wire multi-function inverter system. The inverter can be operated in grid-connected or stand-alone mode to act as a renewable-energy ac power-supply system. In the stand-alone mode, since the D-Σ digital control law includes load impedance estimation, the inverter can track sinusoidal...
Smooth mode transfer of voltage source inverter (VSI) between grid-connected and stand-alone modes is achieved by operating the inverter in voltage control mode (VCM). However, this operation produces some adverse practical issues such as requirement of large rating VSI, limited real power injection by VSI, negligible operational capability in strong grid, frequent mode transfer, and reactive power...
The coupled-inductor single-stage boost inverter (CI-SSBI) has been proposed and applied to photovoltaic (PV) power system. The CI-SSBI based grid-connected PV system integrates some characteristics together in one stage, including boost inversion, feeding current to the grid with high power factor, and maximum power point tracking (MPPT). Moreover, system reliability can be improved by using the...
The development of static power converters capable of transforming DC energy obtained from alternative sources into AC has become one of the main challenges in renewable energy systems. In this context, this paper presents a Stand-Alone Transformerless Hybrid Single-Stage Inverter that works with fully controlled waveforms of output voltage and input inductor currents. It also promotes high voltage...
In this paper, the droop controlled parallel inverter systems with virtual inductor is considered under the unequal resistive-inductive combined line impedance condition which causes the reactive power sharing error. Here, the reactive power sharing error can be reduced by considering each line impedance voltage drop. But if the parallel inverter system is in high power level with large output current,...
This study presents a new circuit topology of the Modular Multilevel Converter (MMC) which is deployed for photovoltaic grid applications. In the conventional MMC, two arm inductors are placed in each phase to limit the circulating current. In the proposed topology, the inductors are replaced by a transformer. The proposed circuit gives a 50% reduction of the voltage rating of the power devices and...
This paper presents analysis of asymmetric single phase Z-source inverter (SPZSI). Small signal model for un-terminated asymmetric Z-source network has been derived. The asymmetric nature of Z-source network leads to formation of up-down glitch in its control to Z-source capacitor voltage transfer functions. The up-down glitch is due to the complex zero frequency falling in between pair of complex...
This study mainly focuses on the development of an adaptive control scheme for a single-stage boost inverter. First, the dynamic model of a single-stage boost inverter is analyzed and built for the later control manipulation. Then, an adaptive control scheme is designed. The effectiveness of the proposed adaptive control scheme is verified by experimental results of a 1kW single-stage boost inverter...
We consider the control design of a grid-connected three-phase inverter which is meant to work with a small power generation unit. A two-level (nested) control system is presented. The inner control loop contains repetitive controllers which assure that the output voltage of each phase can track a sinusoidal reference voltage. These voltages are applied to the local loads, which are separated from...
In this paper a transformerless voltage source sine wave inverter is proposed. A previously developed tri-state boost converter is utilized for the stepping up operation. In this topology the dynamic response of the inverter is increased, by avoiding the right hand plane zero in the converter's small-signal control-to-output transfer function when operating in the continuous conduction mode. The reference...
Model Predictive Control (MPC) becomes more prevalent in power converters due to its faster response in tracking the reference values of the controlled variables. In this paper, the MPC is applied on the Switched-Inductor quasi Z-Source Inverter (SL-qZSI) topology. The MPC modeling for the capacitor voltage, inductor current, and output load current of the topology are designed to predict their values...
This paper proposes a circuit that combines the class E inverter with DC-DC converter so as to provide dual controllable outputs. This study is motivated because the industrial equipment often needs different voltage sources to operate, yet with an inadvertent choice of parameters in the isolated converters, the voltage quality is often highly affected. Therefore, by connecting an auxiliary power...
This paper presents a multipurpose converter for solar photovoltaic (PV) systems. The main purpose of this converter is to serve as a transformerless grid connected inverter having solar PV array at its input. In addition to this the same converter can be employed for catering to dc load simultaneously. The aforementioned dc load can be supplied from the PV array and/or the grid. Thus the proposed...
This paper presents the performance analysis of various control and modulation methods of Z-source inverter (ZSI). The ZSI employs a unique impedance network consisting of L & C elements which couples the voltage source and the converter circuit. It overcomes the difficulties in the traditional voltage source inverter (VSI) and current source inverter (CSI). To analyze the performance of different...
An integration and operation of single phase bidirectional inverter with two buck/boost maximum power point trackers (MMPTs) is provided for dc distribution system. In a dc distribution system a bidirectional inverter is required to control the power flow between dc bus and ac grid, and to regulate the dc bus to the certain range of voltage. A droop regulation mechanism is followed to reduce the capacitor...
The requirements of generating various low frequency voltage waveshapes are usually catered by using linear amplifiers, which results in low overall efficiency. High frequency voltage source inverters with low pass filter at the output are not suitable for these applications, as it is difficult to produce waveshapes containing high frequency components, and variation in frequency. A Boost Inverter...
This paper presents a Scott-transformer based Power Factor Correction (PFC) rectifier for a three-level Neutral-Point-Clamped (NPC) inverter fed Induction Motor Drive (HMD) for enhanced power quality at AC mains. Here, the Scott-transformer based PFC rectifier is digitally controlled by a current feed-forward control. The torque component of the stator current is added to the output of the DC bus...
This paper proposes a reactive current control method focusing on a copper loss reduction for a dual active bridge DC-DC converter. The proposed method controls the reactive current using the fundamental wave model of the primary and secondary voltages in the dual active bridge DC-DC converter. However, the total power factor reduced by the harmonic component of the output voltage of the each inverter...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.