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Electricity access is a key enabling factor for human development, yet over 1.2 billion people have no connection. Minigrids, grid extension and standalone systems are the standard approaches to electrification, but each have significant limitations, including cost of energy, speed of deployment and lack of flexible upgrade paths. Interconnection of minigrids and Solar Home Systems (SHS) to allow...
This paper develops a model to show the effects of soft errors on power flow calculations. We create artificial bit-flips and apply them to solve linear equations obtained in Fast Decoupled Load Flow (FDLF) method. With this, we aim to represent the sensitivity of FDLF iteration against soft errors with a statistical view by using different numerical fault injection scenarios. The study focuses on...
In this paper, application of demand response to accommodate maximum PV power in a low-voltage distribution network is discussed. A centralized control based on model predictive control method is proposed for the computation of optimal demand response on an hourly basis. The proposed method uses PV generation and load forecasts, network topology and market price signals as inputs, limits of network...
Integration of DGs in utility networks has increased significantly over the past years primarily as a result of growing energy demand, coupled with the environmental impacts posed by conventional fossil fuel-based generation. Improper planning of grid integration of intermittent DGs such as wind and solar PV may however pose negative impacts on the quality of power supplied by utility networks. This...
This paper introduces and compares a decentralized and centralized model predictive control scheme for power tracking in a multi-terminal HVDC system based on MMCs. The MPC scheme requires a prediction, which is implemented by treating the HVDC system as a black box. With this approach it is possible to use an MPC scheme without detailed knowledge about the controlled system, which eases the design...
Renewable Energy Sources (RES) have become an alternative form of energy in distribution networks. The 2010/31/EU Directive requires each new building to be highly energy efficient, with a large portion of its energy needs to be supplied by RES either locally or from a nearby source, from 2020 onwards. This paper emphasizes on the optimal utilization of the Photovoltaic (PV) energy produced in a building...
The potential benefits of lithium-ion batteries in the domestic sector are investigated. A particular household in UK with a PV panel of 4kW and a lithium-ion battery is selected. The benefits gained are estimated based on a CBA, taking into consideration the degradation phenomenon. In the suggested methodology, a simulation Matlab model is developed where a specific energy management strategy is...
A conventional 3-level PWM Inverter and a Cascaded Multilevel Inverter, both rated at 230Vrms voltage output and 3KW are analysed using the Switching Function. The PWM signal for the 3-level inverter is derived by applying the Switching Function Technique to the equal area principle. For the Cascaded Multilevel Inverter the Switching Function Technique is initially applied to each H-bridge, and then...
This paper presents a deterioration diagnosis circuit for Lithium ion (Li-ion) batteries using a Field Programmable Gate Array (FPGA). The terminal voltage of any Li-ion battery rapidly increases at the end of the discharging, and gradually converges to the internal voltage. The internal impedance of the battery can be obtained from the transient characteristics. The internal impedance has a close...
This paper presents a novel cluster-based approach for operation and control of multiterminal offshore high-voltage dc (HVDC) grids equipped with voltage source converter (VSC) technology. While conventional optimal power flow algorithms for ac transmission systems focus on minimizing generation costs, wind forecast uncertainties and future bulk power transfers preset by contracts between Transmission...
This paper present modal and acoustic analysis for the stator of a permanent magnet synchronous machine, used for the propulsion of an electric scooter. In order to estimate the vibration behavior, modal analysis was numerically employed. For the electromagnetic noise level, again a numerical study was carried out in order to prove the fitting within the current standards.
The control of modern electrical power systems is, in some respects, limited by traditional analogue control methods. It is recognised that digital control can offer significant advantages in enhancing a power system's closed-loop performance and improve control implementation over traditional analogue methods. In particular, an electrical power system can exhibit optimum performance throughout its...
This work aims at the study and analysis of the influence of coordination and selectivity of protection devices on the reliability of electricity distribution networks. A methodology will be present for the implementation of a computational system that has as main points the integrated analysis of short circuits, coordination and selectivity of protection devices and calculations of reliability indicators...
This paper deals with the development of strategies of observer and controller which allows the balancing in a close loop of the floating voltages of a multi-cellular converter. More specifically, a sliding mode control algorithm and observer is designed for the floating voltages in the multi-cellular converter. The first part of the paper deals with the importance implementation of a sliding mode...
Every year the popularity of the net metering system, for small producers of energy in the Brazilian electric system is increasing fast driven by the Normative Resolutions REN 482/2012 and REN 687/2015 of the National Electricity Agency (ANEEL). These resolutions can encourage investment in the sector and create the growth of renewable energies in the energy matrix through distributed generation (DG)...
Aiming to improve their performance in solve operation center's function, the power utilities have invested in strategies to contribute with the effectiveness of their resources, reducing the costs of provided services and ensuring the continuity and quality of the distributed energy. Considering the orders dispatch to repair crew, that respond for service demands, this paper proposes a predictive...
This paper presents a new mathematical model for the power losses of the PV inverters for various PFs using the datasheet of the PV inverter manufacturer and basic knowledge of power electronics and semi-conductors. The mathematical model uses as parameters the input and output power of the inverter, the PF (inductive or capacitive), which the inverter operates at, and the efficiency curve of the...
Positive corona discharge activity along glass surfaces, in pure form and coated with room temperature vulcanized silicone rubber (RTV SIR), bridging a short needle-plane gap is investigated under positive ramp high voltages. The case or air alone was considered as reference. At applied voltages just sufficient for discharge inception up to values causing flashover, the discharge current and the associated...
This paper examines the development of load signatures based on odd order harmonic current vectors. A measurement setup is developed, and measurements concerning stand-alone and combined operation of several appliances in steady state have been performed using the fundamental voltage phase angle as the angular reference. The proposed load signatures consist of the first three harmonic order currents...
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