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Active power filters are used to improve the energy quality of the electrical distribution networks by the harmonic elimination and correcting of the power factor. However, many conventional configurations of active filters are constituted by a significant number of semiconductors that generate a crowded installation with a complicated control, high cost price of his designs and power losses due to...
This paper focuses on design analysis issues of direct driven permanent magnet synchronous generator (DDPMSG) which are widely used in large scale wind turbines. The permanent magnet synchronous generator (PMSG) of 1.5 MW output power which is driven directly without gear system is analyzed by Maxwell 2D RMxprt. The characteristics of generator include the cogging torque, induced coil voltages at...
To improve the ability of reactive power support at Ultra High Voltage Direct Current (UHVDC) project sending and receiving terminals, State Grid Corporation will install large synchronous condensers which gives high requirements in transient and dynamic characteristics. Some performance indexes of large synchronous condenser are very different from traditional turbo-generator. The change of performance...
In this paper, fast and reliable operation fault classification is carried out using energy of the detail coefficients of the phase signals. Daubechies 4 wavelet was chosen because of its success in detecting abrupt changes in power system signals. The MATLAB 7.10 version is used to generate the fault signals and verification the algorithm. A scheme is proposed for 220KV Karad to Miraj STATCOM connected...
This study proposes an integrated circuit fault prediction technique, which is based on delay characteristics of the clock network. A typical digital integrated single road was used as the example to study the responses of the clock network delay signals to the integrated circuit failures, and analyzed the feasibility and effectiveness of the method in detail. The experimental results show that the...
In view of the critical suction effect of the forced draught fans in the air-cooled steam condenser (ACSC), it is momentous to investigate and optimize the fan mode to acquire a better synthetical performance of the power plant. A verified numerical model of a 2×600MW power plant [1] is specified to discuss the influence from the different rotating speed regulation schemes on the performance of the...
Negative impacts! of the grid faults! in the Doubly Fed Induction Generators (DFIGs) based wind turbines systems include the stator and rotor over currents, DC-link over voltage, electromagnetic torque oscillations, active and reactive power fluctuations at the grid connection point, potentially leading to destabilization of the power system network. For eliminating of the negative impacts, thus enhances...
With the application of a variety of high-tech, life cycle cost of aviation equipment increased substantially. For the life cycle cost of aviation equipment, the costs of using phase account for more than 50% of total costs. Therefore, the development of aviation industry call for a method to evaluate and predict the use phase affordability of aviation equipment. This paper defines the definition...
The purpose of this paper is to evaluate remaining useful life (RUL) of machine tools, which is a key indicator for equipment maintenance and health management. The proposed method takes the factors of reliability, maintainability and economy into account and constructs the evaluation index system based on analytical hierarchy process (AHP) method. Euclid approach degree is then calculated through...
Online monitoring of tool wear condition is of great significance to manufacturing system. In order to adaptively adjust the length of sliding time window, dynamically update the prediction model, and ultimately improve the monitoring accuracy under limited number of available training samples, an adaptive dynamic non-bias least squares support vector machine (ADNLSSVM) is adopted to build tool condition...
This article presents an automated vibration monitoring system for a lathe machine. This study was motivated by the fact that machine production time was wasted during planned maintenance when, most times, the machines did not require any maintenance at all. Also, the periodic intervals used did not depict the correct ageing of the machine components which resulted in unexpected failure of the machine...
The power source is a design characteristic for a mobile robot in which the energy source used must provide enough power for a desired period of time depending on the specific task of a robot. Batteries are the most common power source of energy on mobile robots. Important factors for selecting battery solution as the power source includes weight of the batteries, maximum power availablility, maximum...
Every machine has mechanical moving parts in recent generate internal stresses in its structure. These efforts are manifested by the vibration of the whole structure of the machine. For the collection of data necessary to analyze the origin of these efforts are often used vibration sensors, whose function is to transform mechanical energy into a proportionate and measurable electrical signal. In the...
The operation system of oil tanker berthing and handling is complicated. Once oil spill accident occurs, consequences are beyond measure. The bosv-tie model is established to have a comprehensive analysis of the causes and consequences of the oil spill during the operation of tanker berthing and handling. The fault tree analysis is applied to analyze the risk factors associated with oil spill, while...
Designing fault-tolerant systems implicates a redundant architecture of most critical system components. Traditional techniques — DMR and TMR, require a compromise with either incapability of a failed system masking or with an extremely high complexity and voter discrepancy. This paper presents a novel, warm redundancy architecture on FPGA based on a 32-bit microcontroller, which eliminates the drawbacks...
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