This paper presents a shunt active power filter (SAPF) topology, based on the concept of a transformer with open-end winding (OEW), for reactive power and harmonic compensations employed in three-phase four wire (3P4W...
详细信息
This paper presents a shunt active power filter (SAPF) topology, based on the concept of a transformer with open-end winding (OEW), for reactive power and harmonic compensations employed in three-phase four wire (3P4W) systems under balanced and unbalanced conditions. The proposed system uses two independent dc-links and two independent converters series connected through transformers. Complete system control, including PWM technique, is developed and a comparison between the proposed SAPF and conventional one is presented as well. Simulation and experimental results are provided to validate the theoretical approach.
This paper proposes three dynamic voltage restorer (DVR) topologies. Such configurations are able to compensate voltage sags/swells in three-phase four-wire (3P4W) systems under balanced and unbalanced conditions. The...
详细信息
ISBN:
(纸本)9781479957774
This paper proposes three dynamic voltage restorer (DVR) topologies. Such configurations are able to compensate voltage sags/swells in three-phase four-wire (3P4W) systems under balanced and unbalanced conditions. The proposed systems in this work use two independent dc-links. The complete control system, including the PWM technique, is developed and comparisons between the proposed configurations and a conventional one are performed. Simulation and experimental results are provided to validate the theoretical approach.
Network interfaces are present in a variety of battery powered computer systems, such as notebooks, ultrabooks, tablets and mobile phones. Considering that the battery life is still a constraint, there are opportuniti...
详细信息
Network interfaces are present in a variety of battery powered computer systems, such as notebooks, ultrabooks, tablets and mobile phones. Considering that the battery life is still a constraint, there are opportunities for power management by reducing the power consumption of idle network interfaces. In this work, a dynamic timeout power policy for network interfaces is presented, incorporating workload estimation and a problem optimization at runtime, thus providing power savings and suitable performance.
An unidirectional three-phase to three-phase dc-link converter is proposed, in this paper. It is composed of three unidirectional ac-dc-ac three-leg converters with a shared-leg. The three-leg converter is composed of...
详细信息
ISBN:
(纸本)9781479957774
An unidirectional three-phase to three-phase dc-link converter is proposed, in this paper. It is composed of three unidirectional ac-dc-ac three-leg converters with a shared-leg. The three-leg converter is composed of a non-controlled leg, two controlled legs and a dc-link. A suitable model and control strategy of the systems, including a synchronization method, are proposed. The synchronization method, associated with the PWM strategy allow the grid currents and load voltages have the same phase angle of the input converter voltages. This method ensures sinusoidal grid currents and mitigate the zero-crossing distortions normally caused by the use of diodes. Simulation and experimental results are also presented for validation purposes.
The penetration of distributed generation is growing, and today it is not unusual to see at the same site, equipment that consumes energy working side by side with power sources. To manage and optimize the use of ever...
详细信息
This article aims to present the methodologies of development, analysis and system design of an Electronic Bengal, with object-oriented and structured methods, trying to establish the main features of these. From this...
详细信息
This article aims to present the methodologies of development, analysis and system design of an Electronic Bengal, with object-oriented and structured methods, trying to establish the main features of these. From this scenario, several methods of system analysis are available for use. Among the studies conducted to develop the system, using automation techniques, are SART (Structured Analysis Real-Time) and UML (Unified Modeling Language) modelings. Each has its peculiarities, both in the way of diagramming and about the script. The project proposes an electronic device with an embedded system that contains a control algorithm to enable vibration and audio electromechanical transducers. The project is an electronic device based on open-source flexible platforms to assist in the orientation and mobility of the visually impaired during their displacement.
This paper presents a topology based on the interconnection of single-phase H-bridge converters and a three-phase converter acting as a shunt active power filter. Contributions for the model, PWM approach and control ...
详细信息
A way to deal with the variations in the link quality of Wireless Sensor Networks (WSN) is the use of strategies for Dynamic Channel Allocation (DCA). The first step to perform DCA is estimating the channel quality, s...
详细信息
ISBN:
(纸本)9781479949113
A way to deal with the variations in the link quality of Wireless Sensor Networks (WSN) is the use of strategies for Dynamic Channel Allocation (DCA). The first step to perform DCA is estimating the channel quality, so that the network nodes can decide if a channel change is needed, and the best channel to be used. This paper proposes a distributed approach with nodes dedicated to monitor channel quality, by using the Received Signal Strength Indication (RSSI) and the Link Quality Indicator (LQI) to identify low quality channels. This approach is acceptable in industrial WSN, since the network deployment can be performed with adequate planning. Furthermore, the sensor nodes do not need to stop their operation for monitoring the channel quality. As a first step, experiments were performed in a real industrial environment to identify the relation between RSSI and LQI traces, and the Packet Error Rate for different channels, by using IEEE 802.15.4 radios operating in the 2.4 GHz band.
This paper presents an ac-dc-ac reversible nine-phase machine drive system. The grid side converter is composed of Y-connected single-phase bridges. As the machine is composed of three three-phase groups, a three-leg ...
详细信息
This paper presents an ac-dc-ac reversible nine-phase machine drive system. The grid side converter is composed of Y-connected single-phase bridges. As the machine is composed of three three-phase groups, a three-leg converters are connected separately to each group. The topology does not make use of input isolation transformers and reduces the power processed by converter switches when compared to that of conventional two-level converter. Moreover, harmonic distortion in voltages generated by the grid side converter is reduced when compared to conventional two-level converter. The model and the control strategy have been developed. Simulation and experimental results are also presented.
暂无评论