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Grasping system dynamic information is helpful for dispatcher in control center to take correct control action in time under emergency condition. Wide Area Measurement Systems (WAMS) has been viewed as an ideal system to monitor power systems since it can provide comprehensive profile and dynamic behavior of the power systems. Whereas, for its demanding request on communication systems, it might not...
Each wired termination in a substation represents a cost associated with engineering, installing and testing that wired point. These costs include the obvious financial labor costs, but also include intangible costs such as installation and commissioning time, potential for human error, panel space, increased resistive burden in circuits, and larger raceways. Additionally, each wired termination represents...
In this paper, an intelligent approach based on system-centric controller to develop a power system stabilizer is proposed. The approach discuss a methodology that designs a hybrid controller with two algorithms, one a Neural Network (NN) based controller with explicit neuro-identifier, and the other, an adaptive controller evolved from a Model Reference Adaptive Controller (MRAC). This design performs...
Corrosive sulfur in transformer oil has been identified to cause sudden and unexpected failures of several transformers in recent years. It has been decades since corrosive sulfur has caused such problems. This paper discusses the problems caused by corrosive sulfur, why the problem has resurfaced, new test methods developed to detect corrosive sulfur, and remedies suggested to prevent further destruction.
Steady-state electrohydrodynamic micropumping through bipolar conduction phenomenon has been investigated experimentally and numerically. A single-stage axisymmetric conduction micropump in the vertical configuration has been proposed in this paper. This micropump consists of four components: high voltage ring electrode, grounded disk-shaped electrode, insulator spacer, and inlet/outlet ports. The...
Various technologies and strategies to reduce specific energy consumption are examined. Results include 16 harvest cycles for 30 cells totalling 62,400 cathodes with a weight of 2,500 Tons. The industrial site was Zaldivar, a Barrick mining operation located at 175 km Southeast from Antofagasta, Chile. The production averages 140,000 Ton/year of copper cathodes. With the technologies tested in this...
In this paper, we put forward a new impedance control method of thyristor controlled series capacitor (TCSC) by modifying variable structure PID feedback of firing angle, aiming at improving the transfer capability of remote wind farms. TCSC can get the best results with nonlinear closed-loop control method, but it is very difficult, if not impossible, to be implemented because a huge amount of data...
Microplasma has advantages of reducing the power and downsizing the entire plasma system. Decomposition of formaldehyde (HCHO) by a microplasma reactor was demonstrated for improving Indoor air Quality (IAQ). One experimental investigation was one pass treatment (5 L/min) and the other one way with a large volume treatment (500 L/min). Removal ratio of HCHO (initial concentration: 0.8 ppm) in one...
This paper presents a simple dynamic overmodulation method to obtain a fast dynamic torque response in DTC of induction machines with constant switching frequency controller. A fast dynamic torque response can be obtained by switching only the most optimized voltage vector during torque dynamic condition. The optimized voltage vector can be identified by comparing the rate of change of torque produced...
This paper presents a robust simmering control for induction hobs. This kind of process is almost impossible to carry out in a domestic cooker where the pot temperature is unknown. We exploit an analytical model of the cooking process to design a QFT-based controller. The resultant controller satisfies all user requirements such as a quick heating up, an accurate temperature control and a fast disturbance...
This paper studies those parameters affecting the shielding angle of the lightning rod (Franklin Rod) above very tall buildings. It is recommended that the shielding angle of the lightning rod is about 45° ~ 60°. The downward lightning leader is modeled by using discrete line charge to consider the exponential distribution of charges through the downward leader. The voltage condition used by Rizk...
Several proposals on multi-phase multi-motor drive systems are given in the literature. This paper focuses on one such configuration with stator windings of two quasi six-phase machines (two set of stator windings with 30° phase displacement) connected in series and supplied from a single six-phase voltage source inverter, forming two-motor drive structure. A simple voltage modulation technique is...
The present paper deals with a generalized control strategy for the following multilevel inverters: Neutral Point Clamped (NPC), H-Bridge, and Load Phase Clamped (LPC). The contribution of this work is to develop, in spite of these devices differences, a common control strategy using simple triangular sinus PWM. By applying Petri Network theory, common configurations of these inverters are established...
In this paper thermal analysis and ampacity evaluation of underground power cables that are placed in PVC ducts are presented. A Streamline-upwind/Petrov-Galerkin (SUPG) stabilized finite element method is proposed to solve the air governing formulations in the region between the cables and the retaining duct in the underground power transmission system. In thermal analysis, a nonlinear-coupled electromagnetic-thermal...
This paper presented an experimental investigation into operating characteristics of RCDs under an unbalanced current. The unbalanced current included the harmonic current, ground fault current, and surge current. A testing system was first set up in the laboratory, and the minimum value of the current causing RCD samples to trip were recorded. To obtain consistent testing results, RCD samples under...
This work presents a system to detect short and open circuits suitable for Optibar® inter-cell bars in copper electrorefining processes. The system is based in Optibar's voltage connecting segments. Voltages are sampled and transmitted via WI-FI to a compatible SQL database every five minutes. The technique proposed performs sliding window analysis on anode-cathode voltages slopes to detect short...
Aligned towards net zero energy building goals, building energy management systems will consider energy utilization efficiency improvement, energy cost reduction and renewable energy technology utilization to serve the local energy loads in building structures with dispersed resources. The distributed management of building energy system in this paper describes a semi-centralized decision making methodology...
A pilot-scale low emission boiler plant which consists of a multi-fuel boiler and a plasma-chemical hybrid NOx removal system was investigated. This plant can achieve carbon neutrality because the multi-fuel boiler uses waste vegetable oil as one of fuels. The plasma-chemical hybrid NOx removal system has two processes; one is NO oxidation by ozone produced from plasma ozonizers, and the other is...
As distributed power sources become increasingly prevalent in the near future, power electronics will be able to provide significant advantages in processing power from renewable energy sources using fast response and autonomous control. Fuel cells, photovoltaic devices and storage batteries sources produce a significant power in hybrid power structure. In this paper, the Uninterruptible power source...
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