• 전기학회논문지
• /
• 제56권11호
• /
• pp.1930-1936
• /
• 2007

According to previously published paper the phase advance angle is adopted to the BLDC motor drive with high speed. The report proposed describes the optimum algorism that phase current is in phase with the initial flat region of back EMF. This report studies the need of more leading phase advance angle compared with in phase concept between phase current and back EMF. In case of high reactance this report proposes the more phase advance angle than in phase. The test results more rms value of phase current and output power due to more phase advance angle than in phase. It will be helped the high power operation of BLDC motor at high speed.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2002년도 하계학술대회 논문집 D
• /
• pp.2070-2072
• /
• 2002

In this paper, advance angle control is described to drive an industrial low voltage SRM(Switched reluctance motor) for a forklift truck by changing velocity and torque. The high current SRM is designed and its phase resistance and phase inductance are very low to inject high current into the phase windings. In this reason, the current has to be built up in the increasing phase inductance part as soon as possible. Therefore, the phase switch must be turned on before the phase inductance increases, and this angle is called as the advance angle. We analyze the changes of the advance angle as its torque and velocity are changed in the real SRM driving experiment. And we propose the way to improve the SRM performance by using the advance angle control.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2001년도 합동 추계학술대회 논문집 정보 및 제어부문
• /
• pp.22-25
• /
• 2001

In this paper, a fuzzy advance angle control method is described to drive an industrial low voltage SRM (Switched Reluctance Motor) for 10kW forklift truck. SRM has a highly non-linear characteristic that is due to change the rotor and stator. And low voltage SRM is designed that its phase resistance and phase inductance is very low to inject high current into the phase windings. In this reason, the proper current control is necessary to drive the low voltage SRM efficiently. SRM has positive torque at increasing inductance region and negative torque at decreasing inductance region. Due to this reason, the current has to be built up in the increasing phase inductance part as soon as possible. Therefore, the phase switch must be turned on before the phase inductance increases, and this angle is called as the advance angle. Also, the phase current has to be dropped before the phase inductance decreases. Fuzzy logic is a flexible and general-purposed method of implementing non-linear functions and as such it is useful in control applications. Consequently, we designed a fuzzy advance angle controller to control the phase current appropriately.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
• /
• pp.232-232
• /
• 2000

switched reluctance motors and drives are increasingly used in industrial applications due to their robust mechanical structure, low inertia and reduction in the rotor losses. As the motor speed increase turn on angle must be advanced to build up phase current. When C-dump converter is applied to switched reluctance motor, the capacitance of dump C has to have proper value. In this paper advance angle for a switched reluctance motor and capacitance of dump C are investigated. Then proper advance angle and the capacitance of dump-C are propose for the industrial low voltage SR motor.

• 전기학회논문지
• /
• 제56권12호
• /
• pp.2127-2134
• /
• 2007

The simulation model has been already developed not for 7 phase but for 3 phase BLDC motor. It is necessary to develop a new simulation model of multi-phase BLDC motor including the phase delay angle especially in the high speed region. In this paper, the suitability of the proposed model is verified through the several computer simulations, and experimented results.

• Journal of Electrical Engineering and Technology
• /
• 제5권4호
• /
• pp.623-630
• /
• 2010

This paper presents the implementation and characteristic analysis of a drive system for a three-phase permanent magnet motor with independent excitation winding that is applicable for electric bicycles. The design features improves the phase current waveform, output power, and torque by using advance angle control. This adjusts the phase angle of each phase current in relation to back EMF. In addition, a DC-side PI current control is performed through PWM generation circuit using a low-cost one-chip microcontroller and a CPLD chip, resulting in reduced system costs. Finally, the validity of this control scheme for driving electric bicycles and output/torque improvement characteristics are verified through analysis and experimental results.

• Journal of Electrical Engineering and Technology
• /
• 제9권6호
• /
• pp.2201-2208
• /
• 2014

In this research, the characteristics of Brush-less DC (BLDC) motor in accordance with winding connection method, both Y-connection and D -connection, has been identified with design methodology simply. BLDC motor has been designed for both winding connections, and their torque analysis has been performed considering ideal current source analysis and voltage source analysis with 6-step control. In addition, to reduce torque ripple of BLDC motor, caused by coil inductance, on voltage source analysis with 6-step control, we have proposed suitable control method which is Phase Advance Control. It is verified that the torque ripple has been decreased by virtue of phase advance control, advancing and widening conduction angle of switching, via performance analysis by Finite Element Analysis.

• Journal of Power Electronics
• /
• 제10권4호
• /
• pp.412-418
• /
• 2010

This paper proposes a new algorithm to generate a reference signal for an active power filter using a sliding-window FFT operation to improve the steady-state performance of the active power filter. In the proposed algorithm the sliding-window FFT operation is applied to the load current to generate the reference value for the compensating current. The magnitude and phase-angle for each order of harmonics are respectively averaged for 14 periods. Furthermore, the phase-angle delay for each order of harmonics passing through the controller is corrected in advance to improve the compensation performance. The steady-state and transient performance of the proposed algorithm was verified through computer simulations and experimental work with a hardware prototype. A single-phase active power filter with the proposed algorithm can offer a reduction in THD from 75% to 4% when it is applied to a non-linear load composed of a diode bridge and a RC circuit. The active power filter with the proposed reference generation method shows accurate harmonic compensation performance compared with previously developed methods, in which the THD of source current is higher than 5%.

• 한국정밀공학회지
• /
• 제12권7호
• /
• pp.19-25
• /
• 1995

Presently, along with the advance of high-technology, the precise measurement of linear displacement has become a staple requirement, and consequently the high resolution with submicron order has also been required in precise positioning and carriaging. In this paper, we advance a propose on a new type of laser encoder based on the principle of phase analysis of the moire fringes from superimposed two gratings. The phase angle as an information of displacement can be accurately calculated by detecting the change in brighness at four points of the fringes. The actual application of four point method to the moire fringes is performed thru microcomputer for general purpose, and the measuring procedure is also studied in this research. As an experimental result, in the case of using 20 .mu. m-pitch gratings, it is validated that this method has the resolution of 0.01 .mu. m and the accuracy of .+-. 0.15 .mu. m over the setting range of 100mm.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
• /
• 제50권11호
• /
• pp.575-582
• /
• 2001

This paper presents a calculating method of switching angle for adaptive switched reluctance motor (SRM) drive of a drill. The operation of the SRM is completely characterized by the flux linked by one phase winding which depends only on the current in that same phase winding and the rotor position. An efficiently adaptive SRM drive is possible on appropriately scheduling the commutation angles with accurate rotor position, supplied current value and speed information. An adaptive SRM drive with reduction torque ripple should be controlled by an optimized phase current control along with rotor position. Therefore, we are suggested a computing method of switching turn-on and off angles for adaptationally SRM operation with varied rotor speed and load. To probe the computing method, we have some simulation and experiment, it is shown a good result that can be computing the optimized switching angles for an electric drill motor.