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Power factor losses represent a significant factor of power losses in both industrial and domestic units. Various methods have been devised earlier to tackle this problem. This paper aims to present an indigenous technique and method which could be used for static power factor correction. It is demonstrated in this work that phase difference between voltage and current can be determined using zero...
The elevated temperature has negative effect not only on semiconductor components, but on discrete capacitors as well. Both the electric parameters and the lifetime can be significantly affected by the temperature. In this paper a new measurement setup is presented that enables the widely used thermal transient characterization method to be used also for the discrete capacitors. This measurement method...
An efficient three phase interleaved DC-DC converter is proposed with inductor current and voltage control. The use of multiple sensors for each phase current is eliminated using current reconstruction. This reduces the number of current sensors and improves the reliability. The inductor current control is achieved using single current sensor which measures DC-link current. The proposed converter...
This paper presents an isolated power converter module for medium-voltage (2.4 kV), high-power-quality (PF ≥ 0.98, current THD ≤ 2%), 50 kW fast charger for plug-in electric vehicles. The proposed high-efficiency (above 96%), and reduced-footprint converter module utilizes off-the-shelf Silicon Carbide (SiC) devices to step down the rectified single-phase medium-voltage input. The developed module...
In this paper, a plug-and-play ripple mitigation technique is proposed. It requires only the sensing of the DC-link voltage and can operate fully independently to remove the low-frequency voltage ripple. The proposed technique is nonintrusive to the existing hardware and enables hot-swap operation without disrupting the normal functionality of the existing power system. It is user-friendly, modular...
Partial discharge (PD) measurements have long been used in laboratory to evaluate insulation condition and as a quality control test for manufactured equipment. However, at recent decade, PD measurement has been widely applied to diagnose different equipment units at operating voltage. Now, data showing dependences of various PD parameters from the insulation aging degree are insufficient. The growth...
Polarization currents and thermally stimulated depolarization currents have been measured from semicrystalline polypropylene samples with varying manufacturing parameters influencing the structural properties. The effect of interfacial polarization on short-circuit TSD is theoretically explained by a simple three-layer model representing different structural regions of the polymer. It is shown that...
The polarization reversal and the ferroelectric hysteresis loop have been studied for copolymers of vinylidene fluoride VDF and trifluoroethylene TrFE with 47.2, 63.0, 70.7, and 86.8 mol-% TrFE in the high voltage field up to 100 MVm−1 at 5 to 100 mHz over a wide range of temperature. The copolymers exhibited two current peaks associated with the polarization process at different field intensities...
The complexity of power systems and the change of demand load at the consumer make it necessary to control the voltage to avoid any unnecessary voltage drop beyond the limits allowed within the international standards and achieve optimum energy efficiency. This paper introduces a simple method that can regulate the voltage of a system without the sophisticated electronic devices. The method that controls...
This paper presents results of impedance measurements of low-voltage (230 VAC) electrical grid at the wall socket. The measurements were performed in context of Power-Line Communication (PLC) in urban and suburban areas. There have been measured complex impedance (magnitude and phase) in 10 kHz – 1 MHz frequency range, covering CENELEC, ARIB and FCC bands. The measurements were performed using low-cost...
This paper presents the study and solution of harmonic present in the 33KV power plant equipment manufacturing industry & passive harmonics filter used in electrical system as a solution. Through this paper we come to know about the harmonics & their significance effect on the system regarding the harmonics distortion caused by non-linear load, effect of resonance due to presence of harmonics...
A novel CMOS demodulation detector for time-offlight applications is presented. It can handle large amounts of background light by removing the resulting common-mode signal at the detector level. A common-mode feedback circuit is used on top of a current-assisted photonic demodulator (CAPD) to remove the incoming light that is not correlated to the modulation signal. A dynamic element matching (DEM)...
This paper presents a 25kW six-level Modular Multilevel Converter prototype. The designed prototype is an industrial power converter that can be used by the industry. The converter is shown together with a high-performance hardware platform control designed for large multilevel converters. The hardware platform is a custom platform based on Zynq-7000 System-On-Chip that provides high processing performance...
This paper presents design and implementation of a Integrated boost-flyback converter (IBFC). Operation of the IBFC is described and its key voltage and current equations are given. The practical design of a 96W, 12V-to-48V, IBFC is demonstrated. Experiment on the prototype IBFC shows that it operates with good output voltage regulation and achieves the highest efficiency of 87%.
The operation of a distributed maximum power point tracking (DMPPT) photovoltaic (PV) system with a current source inverter (CSI) is confirmed. We proposed a current-linked distributed PV system instead of a voltage-linked one. All the previous studies of DMPPT PV systems use a voltage source inverter (VSI). Moreover, all commercial power optimizers that are provided by Solar Edge, Solar Magic, Tigo...
This paper aims to focus on the smooth output of Buck converters under the input perturbations and load disturbances using the high-order sliding mode controller with a differentiator (HOSMD) based on the only measurement of output voltage. Theoretical analysis and design procedures of the controller designed by prescribed control law, one of the high-order sliding modes, are presented in detail....
In microgrid systems one or more inverters should be grid-forming in order to control the voltage during island mode operation. Usually the voltage regulation is operated controlling the capacitor voltage of the LCL filter interconnected between the converter and the load. In the present paper a cascade control is proposed for a Three-Level Neutral Point Clamped (3L-NPC) inverter where the voltage...
In this paper a new voltage measurement technique for modular multilevel converter (MMC) capacitors is proposed. While all the capacitors voltages should be known for closed loop control of MMCs, only the arms voltages are measured employing the proposed method. Therefore, the number of voltage sensors reduced dramatically to one per arm. The capacitors voltage quantities are updated continuously...
Series-series (SS) compensation is widely used in contactless power transfer (CPT) for electric vehicle because of their constant current and constant voltage charging features. In this paper, a mathematical model of SS compensation for CPT system is presented. This model includes the effects of harmonics on parameters of SS compensated CPT system. Fourier series analysis is used for mathematical...
This paper presents a fully integrated capacitive DC-DC converter with a wide input voltage range. The folding Dickson converter is used to implement four discrete voltage conversion ratios, capable of operating over a wide input voltage range. A subconverter is added, enabling four additional voltage conversion ratios, improving the input voltage resolution from Vout to 1 Vout. This way, the extra...
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