IEEE Transactions on Industry Applications

Various line-start permanent-magnet (PM) machines have been around for many years: these offer the advantages of line-starting as an induction machine and running synchronously as a PM machine, both from a fixed-frequency supply. The major disadvantage is the uncertainty of successful synchronization, particularly with loads combining high inertia with high load torque. Virtually all conventional ... View full abstract»

Our recent observations suggested that harmonics in the field current are very promising to detect stator interturn faults in synchronous machines. So far, an increase in some of the even harmonics in the field current has been reported to detect such faults. However, no explanation has been provided for the cause of these harmonics. Moreover, the even harmonics can significantly increase with sup... View full abstract»

The torque produced by a synchronous reluctance machine (including the permanent-magnet-assisted machine) is studied analytically, with the aim of pointing out the effect of the position of the flux barriers on the torque ripple. It is verified that the position of the flux-barrier ends highly influences the torque waveform. With the aim of reducing torque harmonic contents, a new strategy is prop... View full abstract»

In this paper, the determination of the end space induction motor heat transfer coefficients is presented, and the methodologies used are examined closely. Two ldquoad hocrdquo prototypes have been built and a test bench completed. This paper reports the setup of the test procedures and results obtained in detail. As the end windings are the hottest points of the motor, particular ca... View full abstract»

This paper proposes a new position sensorless control for interior permanent-magnet synchronous motor (IPMSM) drives fed by overmodulation mode pulsewidth modulation (PWM) voltage source inverter. It is attractive to expand the speed range of the IPMSM for application to electric vehicles, electrical household appliances, and so on. An overmodulation mode PWM voltage-source inverter makes it possi... View full abstract»

This paper presents a novel dual-stator hybrid excited synchronous wind generator and describes its structural features and operation principle. The no-load magnetic fields with different field currents are computed by 3-D finite-element method. Static characteristics, including the flux-linkage and EMF waveforms of stator windings, and inductance waveforms of armature windings and field winding, ... View full abstract»

This paper presents a new permanent-magnet (PM) brushless machine for wind power generation. This machine adopts an outer-rotor topology, aiming at capturing wind power directly. In order to achieve high power density, a high-speed PM brushless generator is artfully integrated with a coaxial magnetic gear. The design details, with emphasis on the special constraints of wind power generation, are e... View full abstract»

This paper presents a cascaded H-bridge multilevel boost inverter for electric vehicle (EV) and hybrid EV (HEV) applications implemented without the use of inductors. Currently available power inverter systems for HEVs use a dc-dc boost converter to boost the battery voltage for a traditional three-phase inverter. The present HEV traction drive inverters have low power density, are expensive, and ... View full abstract»

This paper evaluates and proposes various compensation methods for three-level Z-source inverters under semiconductor-failure conditions. Unlike the fault-tolerant techniques used in traditional three-level inverters, where either an extra phase-leg or collective switching states are used, the proposed methods for three-level Z-source inverters simply reconfigure their relevant gating signals so a... View full abstract»

An all-scalar-control and pulsewidth-modulation (PWM) approach for the four-leg-inverter (FLI)-based three-phase transformerless four-wire power supply (PS) is proposed. The output voltage of each phase is controlled independently, and its controller is formed by a stationary-frame resonant-filter bank accompanied with proportional-control and output-capacitor current-based active-damping loops. T... View full abstract»

This paper presents a three-phase voltage-source 36-pulse converter that draws almost sinusoidal currents. The converter results from the combination of a series-connected 12-pulse voltage-source rectifier with a passive voltage-injection circuit and a bidirectional switch, referred to as hybrid injection. The voltage-injection circuit uses a single-phase rectifier bridge and a single-phase transf... View full abstract»

This paper describes the design, implementation, and performance of a medium-size distribution-type static synchronous compensator (D-STATCOM) with the simplest two-level three-leg voltage-source converter (VSC) topology. Reactive-power control is achieved by phase-shift-angle control, and VSC harmonics are eliminated by selective harmonic elimination method (SHEM). VSC has been designed at the hi... View full abstract»

This paper deals with a new control method for power factor correctors. Control is carried out by a standard IC controller for peak current-mode DC-DC converters, with only an additional compensation ramp generator and peak detector. The fact that neither an analog multiplier nor an input voltage sensor is needed to achieve quasi-sinusoidal line waveforms makes this method very attractive. The met... View full abstract»

This paper presents a novel sinusoidal pulsewidth modulation control method with voltage balancing capability for the diode-clamped five-level rectifier/inverter system. A complete analysis of the voltage balance theory is given. The voltage balancing effects of the third harmonic offset injection to all three-phase voltages are discussed. The proposed control utilizes the offset voltage to regula... View full abstract»

A new thermal model, which allows temperature distribution determination inside a supercapacitor cell, is developed. The model is tested for a supercapacitor based on the activated carbon and organic electrolyte technology. In hybrid vehicle applications, supercapacitors are used as energy-storage devices, offering the possibility of providing the peak-power requirement. They are charged and disch... View full abstract»

This paper proposes a fuzzy-logic-controlled superconducting magnetic energy storage (SMES) scheme for the stabilization of grid-connected wind-generator systems. The control scheme of SMES is based on a sinusoidal pulsewidth-modulation voltage-source converter and a two-quadrant dc-dc chopper using an insulated-gate bipolar transistor. A comparative study is carried out between the proposed fuzzy... View full abstract»

The well-established advantages of resonant converters, including simplicity of circuit configuration, ease of the control scheme, low switching losses, and low electromagnetic interference, among others, have led to their attracting more interest. This work develops a highly efficient battery charger with an improved series-loaded resonant converter for renewable energy applications to improve th... View full abstract»

The use of tribocharging as a potential method to provide sufficient charge to several different lunar simulants for electrostatic beneficiation was investigated. The objective was to determine whether specific minerals of interest (e.g., ilmenite) that are present in lunar regolith could be enriched in concentration by beneficiation that would therefore allow for more efficient extraction for ... View full abstract»

Recent work has demonstrated that airborne bacteria can carry high net charges which may influence their deposition onto surfaces. This paper investigated the relationship between surface electric potential relative to ground and the deposition rate of airborne bacteria. Nutrient-agar settle plates were charged to potentials of +/-5, +/- 2.5, and 0 kV and microbial deposition (CFU/cm2mi... View full abstract»

This paper is aimed at characterizing two possible designs of star-connected three-phase capacitors developed for utilization with the protection schemes of industrial installations. A superficial charge simulation program was employed for estimating the capacitances of one design. The results pointed out the influence of various geometrical parameters on the magnitude of the mutual capacitance be... View full abstract»

Multivariate control charts are commonly used for monitoring processes, the quality of which is determined by two or more correlated output variables. The aim of this paper is to point out the effectiveness of multicriterion control charts for supervising the variability of the outcome of an electrostatic separation process. The experiments were carried out on samples of chopped electric cable was... View full abstract»

The variability of the outcome is often deplored by the users of electrostatic separation equipment. A slight modification of the composition of the processed material, a change in the environmental conditions, or an alteration of the electrode configuration may cause objectionable fluctuation of product quality. Thus, the purity of the copper product recovered from electric cable wastes can easil... View full abstract»

Permanent-magnet synchronous generators (PMSGs) are commonly used for small variable-speed wind turbines to produce high-efficiency, high-reliability, and low-cost wind power generation. This paper proposes a novel control scheme for an interior PMSG (IPMSG) driven by a wind turbine, in which the d-axis and q-axis stator-current components are optimally controlled to achieve the maxi... View full abstract»