Signal Processing and Renewable Energy
Volume:3 Issue: 3, Summer 2019

Increasing penetration of renewable energy resources, especially wind power in power system operation, has some technical and economic effects because of the variable and uncertain nature of these resources. Therefore, it is very important for system operators to consider these behaviors necessary to solve the problem in this regard, especially generation scheduling problem. One of the most important strategies to increase the benefit of power system operation is to manage and control of wind power generation using pumped storage plants. A pumped storage plant can be used to provide added value to a wind farm to manage power output uncertainties. This paper presents a new approach for solving the weekly generation scheduling including wind farms and pumped storage plants. The hybrid PSO mechanism is suggested to solve this scheduling problem based on implementation of bacterial foraging concepts. The proposed PSO is applied to two test systems (which are included two wind farms and one pumped storage plant) and the results of this modified PSO are compared with the conventional PSO. Evaluation of the results of these test systems’ solutions show that better optimal schedules are obtained.

Transient voltage increase in electricity networks is of great importance due to security of devices and insulation considerations. One of the factors which results in transient voltage increase is connection switching. This overvoltage cannot be measured and recorded via usual measurement devices. In this study, possibility of using power quality analyzer for recording and measuring transient overvoltages is studied. To this end, switching in a 20KV electricity network in Imam Khomeini airport city is simulated using EMTP-RV. Then, real switching is performed and overvoltage is measured by power analyzer. Then, these two methods are compared.

Equalization is a kind of the preferred methods for increasing the efficiency of modern digital communication systems. The paper contribution lies in using a modified version of Sliced Mul-ti-Modulus Algorithm (S-MMA) and genetic algorithm (GA) for updating per-tone equaliza-tions taps in the OFDM modulation using too long complicated fading channel, present of dif-ferent noises and ISI impairment. For more efficiency, it is assumed that the channel impulse response is longer than the cyclic prefix length and as a result, the system will be more efficient but at the expense of the high ISI impairment. Both mathematical analysis and computer simu-lations demonstrate the better performance of the new proposed application of the S-MMA and GA are compared to commonly used equalizer methods such as the LMS, RLS and multi modu-lus algorithm (MMA) in the channels with AWGN, burst noises and ISI impairment simultane-ously. Therefore, the new modified S-MMA equalization and GA are good candidates for high speed and real-time applications such as DAB, WiFi, WiMAX, and DVB systems.

The purpose of this article is to troubleshoot and detection a partial discharge in cross-linked polyethylene (XLPE) cable by combining two very-high-frequency (VHF) and acoustic emission (AE) sensors, which is a novel approach to troubleshooting. The small size of these signals is the main problem in partial discharge (PD) measurements, which might cause the signal mix completely with noise and make troubleshooting difficult. Hence, attention has been paid to high bandwidth to eliminate disturbing noise. In this paper, Rogowski's coil is designed as a kind of VHF sensor for troubleshooting purposes. Then, it simulates and examines the characteristics of the partial discharge in the power cables that have been occurred due to the existence of a cavity. In the end, in order to prove the efficiency of the intended method, the actual partial discharge test was performed using the VHF and AE sensors. The combination of two VHF and AE sensors is capable of eliminating electrical interference and electromagnetic noise in the test site, as well as identifying different types of discharge, and providing a model for troubleshooting partial discharges in online and offline tests. In addition, due to the simple design and installation of the sensor in the equipment and have not to need to cut off equipment from the network, this method is economically very cost effective.

According to the neuroscience, studies on third generation of neural networks called spik- ing neural networks (SNN) have been developed recently. SNNs are used to model natural comput- ing of the brain. Spike train based networks are investigated as signal processing of the brain is an objective. This paper propose a digital hardware implementation of a single spiking neuron. The neuron is used as a direct digital frequency synthesizer. The proposed architecture uses leaky integrate and fire (LIF) neuronal model which is easy to implement. Inter spike interval (ISI) of the input and the output spikes are used as coding scheme. A FPGA platform is utilized due to its flexibility and real time applications. The simulation results of both Matlab and Quartus II indicate acceptable accuracy of the proposed design compared to the related works. The Verilog language is used for hardware simulation. The maximum operating frequency of 250 MHz is reached on Cyclone III device.

Substrate integrated waveguide (SIW) filers are good candidates to substitute for bulky and expensive metallic waveguide filters. Many methods are used to developed specific filter responses. One of them is using defected ground structures (DGS) in SIW filters to generate desired transmission zeros, which cannot be used in waveguide filters. In this paper, an elliptical third order bandpass SIW filter is designed in WLAN frequency band using the DGS technique. It is also shown that this technique reduces the filter size while providing good filtering response. The central frequency and fractional bandwidth of the filter is 2.4 GHz and 16.2%, respectively.