Autonomous power system brassboard

The Autonomous Power System (APS) brassboard is a 20 kHz power distribution system which has been developed at NASA Lewis Research Center, Cleveland, Ohio. The brassboard exists to provide a realistic hardware platform capable of testing artificially intelligent (AI) software. The brassboard's power circuit topology is based upon a Power Distribution Control Unit (PDCU), which is a subset of an advanced development 20 kHz electrical power system (EPS) testbed, originally designed for Space Station Freedom (SSF). The APS program is designed to demonstrate the application of intelligent software as a fault detection, isolation, and recovery methodology for space power systems. This report discusses both the hardware and software elements used to construct the present configuration of the brassboard. The brassboard power components are described. These include the solid-state switches (herein referred to as switchgear), transformers, sources, and loads. Closely linked to this power portion of the brassboard is the first level of embedded control. Hardware used to implement this control and its associated software is discussed. An Ada software program, developed by Lewis Research Center's Space Station Freedom Directorate for their 20 kHz testbed, is used to control the brassboard's switchgear, as well as monitor key brassboard parameters through sensors located within these switches. The Ada code is downloaded from a PC/AT, and is resident within the 8086 microprocessor-based embedded controllers. The PC/AT is also used for smart terminal emulation, capable of controlling the switchgear as well as displaying data from them. Intelligent control is provided through use of a T1 Explorer and the Autonomous Power Expert (APEX) LISP software. Real-time load scheduling is implemented through use of a 'C' program-based scheduling engine. The methods of communication between these computers and the brassboard are explored. In order to evaluate the features of both the brassboard hardware and intelligent controlling software, fault circuits have been developed and integrated as part of the brassboard. A description of these fault circuits and their function is included. The brassboard has become an extremely useful test facility, promoting artificial intelligence (AI) applications for power distribution systems. However, there are elements of the brassboard which could be enhanced, thus improving system performance. Modifications and enhancements to improve the brassboard's operation are discussed

Enhancing the stability of an autonomous microgrid using DSTATCOM

This paper proposes a method for power sharing in autonomous microgrid with multiple distributed generators (DG). It is assumed that all the DGs are connected through voltage source converter (VSC) and all connected loads are passive, making the microgrid totally inertia less. The VSCs are controlled by either state feedback or current feedback mode to achieve desired voltage-current or power outputs respectively. A modified angle droop is used for DG voltage reference generation. Power sharing ratio of the proposed droop control is established through deriva-tion and verified by simulation results. A distribution static compensator (DSTATCOM) is connected in the microgrid to provide ride through capability during power imbalance in the microgrid, thereby enhancing the system stability. This is estab-lished through extensive simulation studies using PSCAD

Design And Implementation Of Electrical Transmission Line Monitoring And Controlling System

As the electric transmission line is spread widely at long distance location is become difficult to monitor, control the power supply in the transmission line. Physical inspection at every location and troubleshooting is not feasible. Same problem is still facing at traffic monitor and control units as every square which are currently controlled manually by operator. Wireless Sensor Network (WSN) provides access over remote location with centralized monitoring and controlling on different channels so it can be utilized for electric transmission line monitoring. While the WSNs are capable of cost efficient monitoring over vast geo-locations, several technical challenges exist. To overcome these problems in regional areas proposed system is designed to monitor and control the electric transmission line using WSN. Here we are building a wireless node which can centrally monitor and controlled through base station or the wireless cluster head. A centralized server will be responsible to see the electric poll status and control the poll activities to enable or disable power in particular area. As it is not feasible to monitor the central server full time, So the proposed system is designed to have emergency alert system for remote user with the help of a GSM modem will be connected to the central server which will send the emergency alert SMS to administrator and user. DOI: 10.17762/ijritcc2321-8169.150712

A Design of Wireless Sensor Networks for a Power Quality Monitoring System

Power grids deal with the business of generation, transmission, and distribution of electric power. Recently, interest in power quality in electrical distribution systems has increased rapidly. In Korea, the communication network to deliver voltage, current, and temperature measurements gathered from pole transformers to remote monitoring centers employs cellular mobile technology. Due to high cost of the cellular mobile technology, power quality monitoring measurements are limited and data gathering intervals are large. This causes difficulties in providing the power quality monitoring service. To alleviate the problems, in this paper we present a communication infrastructure to provide low cost, reliable data delivery. The communication infrastructure consists of wired connections between substations and monitoring centers, and wireless connections between pole transformers and substations. For the wireless connection, we employ a wireless sensor network and design its corresponding data forwarding protocol to improve the quality of data delivery. For the design, we adopt a tree-based data forwarding protocol in order to customize the distribution pattern of the power quality information. We verify the performance of the proposed data forwarding protocol quantitatively using the NS-2 network simulator

Emerging Works on Wireless Inductive Power Transfer: AUV Charging from Constant Current Distribution and Analysis of Controls in EV Dynamic Charging

Wireless power transfer through inductive coupling, termed as inductive power transfer (IPT), is one of the important technologies in power electronics that enable transfer of power between entities without physical connections. While it has seen significant growth in the areas such as electric vehicle charging, phone charging and biomedical implants, its emerging applications include charging of autonomous underwater vehicles (AUVs) and dynamic charging of electric vehicles from the roadway. This dissertation addresses a few key challenges in these areas of IPT applications, paving the way for future developments. For the WPT for AUV, the recently developing sea-bed installed marine systems are targeted, which typically gets power from on-shore sources through constant dc low-current distribution. As the present underwater IPT topologies are not suitable for such applications, this dissertation proposes underwater IPT topologies to interface directly with such constant current distribution and provide a constant voltage output supply to the on-board systems inside the AUVs. The considerations for seawater losses and the small-signal models for control purposes are also addressed. Analysis and experimental results are provided for validations of the analytical designs and models. In the area of electric vehicle dynamic wireless power transfer (EV DWPT), the comparison of control performances of different coupler, compensation topologies and control implementations are addressed. The effect of communication latency on control bandwidth are also addressed. The outcomes are presented through analysis and simulations, and based on that future research recommendations are made to pave way for future commercial developments of well regulated and interoperable EV DWPT systems

Control of an Autonomous Hybrid Microgrid as Energy Source for a Small Rural Village

Nowadays, the exhaustion of electricity power in rural areas is becoming an important issue for many African Nations. Moreover, challenges include the high cost of extending the power grid to these locations, the economic health of the utilities and lack of revenue in impoverished villages. Numerous new initiatives are being implemented in the countries some of them co-financed by international organizations. In this paper, the hybrid microgrid is carried out as a feasible solution for a small rural village. A model of hybrid microgrid consisting of combination of photovoltaic (PV) panels and battery energy storage (BES) and a control system for managing the components of entire system to feed the village as local load is proposed. The control system must avoid the interruptions of power delivered to the consumers (village) and, therefore, good quality and reliability of system is required. The PI controllers are used to regulate the voltage and current using three-phase dq transformation, while the parameters are determined using Ziegler-Nichols tuning method. The effectiveness of the proposed method is verified by simulation results given by the Matlab/SimPowerSystems environment.