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This paper describes a new algorithm for selection of faulty circuit in parallel series-compensated lines. It suits for protection of such lines and uses one-end phase currents measurements only. The developed method has been tested and evaluated using signals obtained from versatile computer simulations. A detailed models of considered transmission line including the SC&MOV banks as well as the...
Grid connected Voltage Source Converters (VSCs) with LCL filters usually have voltage measurements at the filter capacitors, while it can be important to control the active or reactive power injection at the grid-side of the LCL filter, for instance at a Point of Common Coupling (PCC). Synchronization to the PCC voltage can be obtained by Virtual Flux (VF) estimation, which can also allow for voltage...
The complexity of electrical energy nets in modern cars is increasing rapidly due to the rising number of dc-dc converters and motor controllers. Multi-converter systems may lead to negative impedance instability that must be avoided in the automotive energy net under all circumstances, including faulty conditions such as a failure of batteries or other energy storage devices. Many stability criteria...
In this study, the characteristics of capacitor are measured by using the function of B-H analyzer. In contrast to impedance analyzer measurement, the B-H analyzer can be used to measure capacitor characteristics under high current amplitude condition that approaches the practical current condition. In addition, the rectangular current waveform of a capacitor can also be measured under variable frequency...
Since passing its commissioning tests in early August 2011, the flexible pulsed dc current source (FPDCS) at ETH's high voltage laboratory has enabled research in different areas of HVDC switchgear as well as its applications with an unprecedented variability and flexibility, establishing many new research opportunities. Over the course of five years of continuous use, a significant number of incremental...
This paper considers the utility of several alternative energy measures to reduce the energy required by a stimulation current source to charge a neuron membrane capacitance to a prescribed value in the case of a single sodium channel. For a simple case, minimizing the energy of the nonlinear channel conductance provides improved efficiency in terms of stimulator energy as compared to minimizing a...
In most substation protection studies, capacitor bank parameters are derived from manufacturer nameplate values. However, the actual parameters could be different from the nominal rating as a result of manufacturing variance, assembling, material aging, and temperature dependencies. Wide manufacturing tolerance could lead to non-negligible calculation inaccuracy that affecting successive studies....
Vibration of AC filter capacitor generates loud noises in HVDC converter stations, which would reach 105dB. Currently, vibration features are not investigated thoroughly. The objective of this work was to measure vibration velocity distribution on AC filter capacitor surfaces and to investigate the vibration features. In the experiments, the capacitor was applied currents consist of three components...
Double-Layer Capacitors (DLC) are becoming popular energy storage elements in several systems such as automotive propulsion systems, renewable energy storage and auxiliary power units. Optimal energy management, estimation and control algorithms for such DLCs heavily depend on sensor measurements, namely voltage, current and temperature sensors. Any fault in such sensors may result in degraded operation...
Dielectric materials with high electrical energy density, low loss, and high thermal stability are desirable for a broad range of modern power electronic systems. Here, we investigate the conduction mechanism at high temperatures and high fields in a semi-crystalline poly(tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride) (THV) terpolymer, which has been shown to be attractive for high temperature...
In this paper we propose and develop a complete solution to measure very low tunneling currents in Non-Volatile Memories, based on the Floating-Gate technique. We aim at using very basic tools (power supply, multimeter…) but still having a very good current resolution. The key node of our solution is that the experiment is led in a very particular low-noise environment (underground laboratory) allowing...
To ensure the transient performances of the singlephase induction motor with three parallel-connected windings, the simulated and experimental researches are carried out detailedly in this paper. At first, the transient simulation model of the motor is established and the simulation analysis is performed. Then the experiments are performed on the prototype motor, to verify the validity of the above...
In this paper we present the realisation of an HVDC experimental platform with modular multilevel converter and two-level voltage source converter. Local control strategies for both converters are outlined in detail. The experimental platform is configured in such a way that the power-flow is controlled by the modular multilevel converter, while the DC voltage is regulated by the two-level voltage...
A DC-link capacitance estimation method is presented for a three-phase voltage-source converter. The measured phase currents and DC-link voltage of the converter are used in formulation of the input and output signals for the estimator. The estimator is based on the ordinary least squares method. The capacitance can be estimated during the startup of the converter or while the converter is in normal...
Electrical equipment like motion detectors, time switches, presence sensors, timers, low power LED lamps or LED night lights have real power less than 1 Watt at the AC grid 230V/50Hz. But if we analyze the circuit topology, there are many conventional resistors to limit the inrush current. With an inrush controller with switched transistor we can eliminate the resistors and improve the efficiency.
This paper presents design and simulation of CMOS circuits intended for on-chip differential-mode charge based capacitance measurements in the femto-farad range. The circuits can be integrated with MEMS sensors in CMOS-compatible technology. The reported circuits are characterized by very high sensitivity and a linear C-V response. The performance of differential CBCM circuits using simple current...
High voltage capacitors are widely used in middle and high voltage laboratories and testing rooms. Capacitors are used for measurement of voltage in the form of voltage dividers. Injection and blocking capacitors are placed in the galvanic systems of partial discharges. And high voltage capacitors are also used in the high voltage as the part of laboratory bridge circuits. Common characteristics of...
The microelectronics industry seeks screening tools that can be used to verify the origin of and track integrated circuits (ICs) throughout their lifecycle. Embedded circuits that measure process variation of an IC are well known. This paper adds to previous work using these circuits for studying manufacturer characteristics on final product ICs, particularly for the purpose of developing and verifying...
Since some years, one solution to increase the power density of the power converters consists to use the wide band gap semiconductors like SiC and GaN. These devices allow having power converters that operating with the high switching frequencies. These fast devices induce of very high variations of the voltage (dv/dt) and current (di/dt) during commutations. The direct consequence is the generation...
Electrical microthruster have been widely applied in micro and nano-satellites, dute to its light weight and low cost. A microthruster based on ferroelectrical plasma is developed to realized microscale Newton thrust applications. Measurement of thrust generated from the ferroelectric miro-plasma thruster(FMPT) is crtical for the design of FMPT. A charge collector based on capacitor charging principle...
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