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A novel IGBT module construction using materials with matching coefficients of thermal expansion (CTEs) to provide longer lifetime and increased reliability will be presented. This technology reduces the stress on solder layers in the module, which tend to fatigue due to the module's flex during heat cycle tests. It will be shown that designs with matching CTEs also reduce the module's susceptibility...
High frequency power electronic converters require lossless, accurate and isolated current measurement. High frequency currents through a Printed Circuit Board (PCB) trace generates a non-uniform magnetic field around the trace. The non-uniform magnetic fields can be normalized by means of utilizing Magnetic Field Concentrators (MCON) using conductive materials. In this work, the effect of different...
This paper presents comprehensive validation tests of a recent qd0-frame core-loss model of three-phase induction machines at different load conditions. The machine is run at different frequencies/speeds and flux levels. These tests reinforce the model at different operating conditions before further model-based analysis and control design. Moreover, to properly use the model, a series of model parameter...
Axial Flux Permanent Magnet (AFPM) motors of two types, coreless and conventional topologies, have been studied in order to identify their merits and drawbacks at different ratings, particularly for in-wheel electric transportation applications. The performance of the coreless with several slotpole combinations and number of disks is evaluated. Design of experiments (DOE) methodology is utilized to...
Common-mode voltage (CMV) by switching pattern of space vector pulse width modulation (SVPWM) excites parasitic capacitance coupling in interior permanent magnet synchronous motor (IPMSM), and it finally causes shaft voltage. Among all parasitic capacitances, winding-to-rotor parasitic capacitance has the greatest effect on the shaft-to-frame voltage. In the study, mitigation method of a shaft-to-frame...
High Efficiency Video Coding (Hevc), the newest video encoding standard, provides up to 50% bitrate savings compared to the state-of-art H.264/AVC standard for the same perceptual video quality. In the last few years, the Internet of Things (IoT) has become a reality. Forthcoming applications are likely to boost mobile video demand to an unprecedented level. A large number of systems are likely to...
The purpose of the paper is to add solutions to the recognition and transport of minerals copper mining in southern Ecuador, using tools that have MATLAB® and LabVIEW®. The algorithm developed in MATLAB® using the principles of image processing to segment and filters the same. Finally applies the theory of neuro-fuzzy for the recognition of the presence of copper in a rock that is modeled. Is important...
Conventional loop antennas for RFID reader usually perform worse with metallic environment. To improve reading range under this condition, a ferrite sheet is incorporated in the conventional loop antenna. The proposed antenna yields similar reading range with or without metallic environment.
Thin metasurface absorbers with stable absorbing frequency in the oblique incident angles have been required. This paper presents the bistatic RCS reduction characteristics of the flat and curved metasurfaces in TE incidence wave. In both flat and curved metasurfaces, when the incident angle increases, the absorbing frequency shifts to higher. However, the RCS reduction decreases as the incident angle...
In the copper electrolytic refining process, the short-circuit failure among the electrodes usually exists. When it occurs, the temperature distribution is often abnormal, accompanied by local or overall overheating. This paper proposes a novel processing method for infrared temperature images to effectively detect the short-circuit fault and locate the accurate malfunctioning spots. The design procedure...
Hybrid excited flux-switching machine (HEFS) is a novel brushless synchronous motor. Compared to conventional permanent magnet synchronous machine (PMSM) and permanent magnet flux switching (PMFS) machine, it has additional excitation winding in its stator to modulate the air-gap magnet field. In this paper, the topology and operating principle of HEFS is analyzed. Its dynamic mathematical models...
At three key sporting venues of the RIO 2016 Olympic Games, an innovative remote powering solution was used to deliver power from a central source to Remote Radio Units (RRUs) located on cell towers. The solution effectively powered the RRUs from a centralized source of DC power while providing battery backup protection. This paper describes the powering challenges faced by the Wireless Service Provider...
Vacuum circuit breakers are widely adopted in middle voltage class. Their application area has continued to spread to higher voltage class. Therefore the importance of electrical insulation technique in vacuum, especially the insulation of electrode gap has been required significantly. This paper describes the research on vacuum breakdown and discharges related to the electrode gap of vacuum interrupter.
Fundamental experiments were made for a DC arc in a separation process of a brush and a commutator segment. Firstly, we constructed an equipment composed of a fixed graphite-electrode (simulating a brush) and a movable copper-electrode (simulating a commutator segment). This equipment employed a sliding-movement separation process of the electrodes. From a waveform measured under a DC source of 12...
To improve the interruption performance of electric switching apparatus, it is important to understand the dissipative process of injected energy between the electrodes. In this paper, the time-resolved energy balance of air arcs is investigated under various currents and gap distances. The total energy injected to the arc is divided into two parts: energy transferred to electrodes which mostly causes...
High Voltage DC (HVDC) transmission systems are preferable in long distances and has an advantage over high voltage AC systems. One of the key equipment in HVDC system is the HVDC circuit breaker because it has a direct influence on the transmission system reliability. This paper presents an investigation of the thermal characteristics of the DC electric arc on the electrode surface with and without...
In this paper, an investigation of arc root behavior on a pair of parallel electrodes is presented. An effective filtering method is introduced to allow the clear observation of arc root behavior. The position of the arc root is identified and tracked by a multi-objective dynamic tracing algorithm. Thus the trajectories and the speeds of arc roots can be obtained. The results show that the movement...
Laboratory of Electrification of Industrials Enterprises (LREEI) of boumerdes and CDTA have developed an in-house Helmholtz coil. It will be used as a source of external magnetic field for studying the Negative Bias Temperature Instability (NBTI) degradation mechanisms that can influence Metal Oxide Semiconductor (MOS) devices. This paper describes the different phases of design and construction of...
According to the characteristics of ship propulsion, the external load characteristics of the direct drive motor are analyzed. The overall design of the propulsion motor is taken as the starting point, and the optimal design of the electromagnetic loss is deduced. From the point of iron loss, copper loss and harmonic loss, to reduce the mechanical loss of the motor; From the point of bearing friction...
Presented is a study of RFIC interconnect methodologies and a possible 3D printed alternative to traditional strategies. Using polyjet 3D printing technology, an easily reconfigurable wide bandwidth interconnect is constructed. Copper conductors are deposited on 3D printed structures, which make connection to an IC by means of conductive epoxy. Simulated and measured results for this structure are...
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