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In order to ensure radio services like radio broadcasting or terrestrial navigation, the electromagnetic emissions of wind turbines (WTs) must be also taken into account. Due to the enormous metrological effort as well as the dependence on the weather condition which influences the power level of the WT, the idea of measuring the common-mode current Icm (also known as antenna current) on the power...
The power factor (PF) levels are established by each country's national standards. In Brazil the lower power factor level allowed is 0.92. In order to monitor this quantity, the present paper uses Arduino to develop a PF metering system. It presents all the necessary theories concerning the calculus of the power factor itself, the programming logic applied to the data acquisition, and the details...
Described are the design, fabrication and measured results of a pair of PHEMT power MMIC chip sets, one operating at 31GHz and the other operating at 35GHz. Each chip set contains a high gain 0.5W driver and a 1.5W power MMIC. The demonstrated high yield and low cost of these MMICs makes them attractive building blocks for today's millimeter-wave systems.
An Unequally Spaced Multi-Tone signal (USMT) is used for the assessment of nonlinear devices and circuits. The statistical properties of the signal are described. The setup measurements for such a signal are given either by using a Large Signal Network Analyzer (LSNA) or a Nonlinear Vector Network Analyzer (Keysight PNA NVNA with SA option). A USMT Load Pull (USMT-LP)set-up has been developed using...
In this paper, we study the radio propagation characteristics in a typical forest environment in central Europe. Understanding propagation in such environment is important not just for remote monitoring and military applications, but also for vehicular networks of cars passing by the forest. We have conducted measurement campaigns covering the frequencies of 750MHz and 2170 MHz. We have also covered...
This paper presents a method to measure the frequency dependent impedance of an electric machine to calculate the additional losses caused by inverter output voltage harmonics. These losses are calculated by combining the calculated inverter output voltage spectrum and the measured frequency dependent impedance of the machine.
This paper presents our research on a 95 GHz magnetron based on the particle simulation and experimental verification. Some important characteristics such as space charge distribution, electron back bombardment and electron secondary emission have been investigated. The measured 5.6 kW output power and long life time enable this magnetron to be applied in the w-band cloud radar.
Power will be a first-class operating constraint for Exascale computing. In order to manage power consumption of systems, measurement and control methods need to be developed. While several approaches have been developed by hardware manufacturers, they are vendor-specific and in some cases implementation-specific interfaces. Integrating all of the individual device level measurement and control functionality...
Nowadays, it can be seen an increasing use of microprocessors in electric motor monitoring systems. Such systems are often used to measure the basic operating parameters of the electric motors, like current, voltage, active and reactive power. The existing measuring methods require relatively high sampling rate for signals measurement and a relatively high computational power for processing the acquired...
Research in high performance computing (HPC) energy optimization is a growing field motivated by cost and environmental drivers. As commodity server platforms are increasingly deployed as affordably scalable compute clusters, the processor and operating system's energy management capabilities also continues to advance in sophistication. This trend creates a large number of configuration and control...
In this contribution a gallium nitride (GaN) based inverse class F (F−1) power amplifier with in situ waveform measurement capability is presented. Which the measurement approach the high frequency time domain voltages and currents in a reference plane can be measured directly in the circuit. Therefore, a directional coupler is integrated in the output matching network of the F−1 power amplifier....
In recent years, power electronics utilization in modern devices has experienced a large growth due to several applications. For this reason, undergraduate laboratory courses in this field should have modern equipment for measurement and analysis of electrical signals. With this, students will have the opportunity to understand theoretical concepts in practice. However, commercial equipment of this...
The number of electronic devices in households as well as in industrial workplaces is continuously growing because of progress in automation. Identifying unusual operating behavior, detecting device failures in advance, and recognizing energy saving potentials are key features to improve the reliability, safety, and profitability of those systems. Facing these tasks, todays research is focused inter...
This paper presents a method for assessing causality in power quality under stationary conditions, resorting to an index tipically employed in graph theory, the centrality index. Subsequently, the method is illustrated by means of two real systems, allowing a comparison among the results obtained from other existing methods. A discussion regarding the results and its interpretation is presented as...
The evolution of energy demand and production can be faced with a Grid that becomes Smart: a network that is capable of integrating heterogeneous players in both generation and demand, allowing each of them to access electricity market and being able to react in real-time and autonomously to changing conditions on the grid. Such paradigm may allow to provide advanced services (i.e. Demand Response)...
In this paper, experimental results obtained with two different types of measurement equipment are presented comparatively. One type of equipment is dedicated to power quality monitoring, while the second one is a phasor measurement unit with a supplementary module intended to be used to determine some power quality parameters. Experiments were designed as to emulate different power quality levels...
In this manuscript, a low-cost power transducer, suitable for the implementation of electrical power meter, is presented. The current sensing unit is based on a Rogowski coil, while the voltage transduction is performed with an active voltage divider. An analog multiplier is adopted to generate the instantaneous power waveform. Active power and apparent power are measured with a digital multimeter...
The measurement of grounding system impedance may be affected by power system frequency interference and its harmonics. The Shifted Frequency Method (SFM) is potentially insensitive to the electromagnetic interference. In this paper, we evaluate this method in the hydroelectric power plant for two different load conditions of the connected overhead power lines. Presented field tests results further...
The paper presents the first findings from workpackage "Increased Observability" in EU FP7 project ELECTRA. Accommodation of intermittent generation into the network and its reliable operation require a gradual evolution of the network structure and in particular improvement of its monitoring or observing. The present practices of observing distribution networks are quite limited and vary...
This paper describes an Inductive Shunt PLC coupler, for coupling wideband PLC signals onto power lines with high efficiency and low distortion and shows how this can be used for measuring PLC frequency impedances of power lines, distribution transformers, motors or any other appliance. The paper presents some impedance measurements of power lines, appliances and distribution transformers.
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