8/7/2019 Writing Engineering Abstracts(38)

1/7

Writing Engineering Abstracts(38)

http://www.chineseowl.idv.tw

http://www.chineseowl.idv.tw/http://www.chineseowl.idv.tw/

8/7/2019 Writing Engineering Abstracts(38)

2/7

:(+)

8/7/2019 Writing Engineering Abstracts(38)

3/7

(1 of 2) (+) While the MOSFETsrequired off-time for achieving the target current iscalculated ahead of time, the MOSFETs on-time ismaintained constant, resulting in variable switchingfrequency. The analog current mode is normally

implemented in switching power supplies to sense andcontrol the peak inductor current. Among the seriousproblems that subsequently arise include poor noiseimmunity, a need for slope compensation and peak toaverage current errors that the inherently low current loop

gain cannot correct. Therefore, this work describes avariable-frequency novel digital current controller for valley,peak or average currents, capable of easily supporting ahigh switching frequency that exceeds 4MHz. For eachvariable of interest (valley, peak or average current), theappropriate PWM method is selected to achieve digital

current control without an oscillation problem.

8/7/2019 Writing Engineering Abstracts(38)

4/7

(2 of 2) The digital current control method is analyzed in variousways. Factors that influence the compensator control are thenidentified. Next, whether circuit design can consider the entireelectrical circuit is considered. Simulationresults indicate that the proposed digital current controller can be

examined under trailing edge modulation Under trailing edgemodulation, the proposed method can experience the sameinstability under operating conditions when the duty cycleexceeds 0.5. Additionally, the proposed digital current controllercan be used in a diverse range of power factor conversionapplications, including rectifiers with power factor correction

(PFC). Doing so requires only one current sample per periodwith relatively modest processing requirements. In addition to complying with requirements of strict outputvoltage regulation, high-speed dynamic response andprogrammability without external passive components, theproposed current controller can be derived for all basic converter

configurations and for valley, peak or average currents.

8/7/2019 Writing Engineering Abstracts(38)

5/7

(1 of 2) (+) Start-up algori thmsprofoundly impact motor control performance, as evidencedby the increasing popularity of highly efficient and highlyintegrated driven ICs. Appropriate start-up control and lowcurrent consumption dominate the overall performance.

However, conventional control procedures adopt either acomplex DSP or MCU system to implement algorithms.The inability to analyze and simplify these algorithms withrespect to the signal process and position estimationmakes it impossible to implement ICs more efficiently.

Therefore, this work presents an efficient algorithm with aneffective start-up control and low output current, capable ofaccurately locating the position of the motor and effectivelydriving it to achieve integration into ICs.

8/7/2019 Writing Engineering Abstracts(38)

6/7

(2 of 2) An experimental platform consisting of a DSP, motor,driven circuit and control software is constructed for estimatingmotors. Software is then exploited to control the motor based onvarious conditions. Next, a table of commands is compiled, alongwith the positions built by observing how control signals and

output results are related. Additionally, the accurate position ofthe motor that reduces the output current for driving motors isdetermined by referring to this table. Moreover, the optimalcurrent to drive the motor is identified by adjusting the speed ofcontrol signals, thus increasing the efficiency of driven motors.Finally, a table and an optimal speed control signal are

developed. Analytical results indicate that theproposed algorithm with an effective start-up control and lowoutput current is easily implemented into IC design. Importantly, the proposed algorithm minimizeshardware implementation and drives motors efficiently to ensureeasy manipulation.

8/7/2019 Writing Engineering Abstracts(38)

7/7

Further details can be found at

http://www.chineseowl.idv.tw

http://www.chineseowl.idv.tw/http://www.chineseowl.idv.tw/