Two 2D phase unwrapping approaches are included:
1. Phase quality guided path following method.
2. Goldstein's branch cut method.
The algorithms are described in:
D. C. Ghiglia and M. D. Pritt, Two-Dimensional Phase Unwrapping:
Theory, Algorithms and Software. New York: Wiley-Interscience, 1998.
This reference design describes the design of a 3-phase AC induction
vector control drive with position encoder coupled to the motor shaft. It
is based on Motorola’s DSP56F805 dedicated motor control device.
AC induction motors, which contain a cage, are very popular in variable
speed drives. They are simple, rugged, inexpensive and available at all
power ratings. Progress in the field of power electronics and
microelectronics enables the application of induction motors for
high-performance drives, where traditionally only DC motors were
applied. Thanks to sophisticated control methods, AC induction drives
offer the same control capabilities as high performance four-quadrant
DC drives.
General Description
The LM621 is a bipolar IC designed for commutation of
brushless DC motors. The part is compatible with both
three- and four-phase motors. It can directly drive the power
switching devices used to drive the motor. The LM621 provides
an adjustable dead-time circuit to eliminate ``shootthrough''
current spiking in the power switching circuitry.
Operation is from a 5V supply, but output swings of up to
40V are accommodated. The part is packaged in an 18-pin,
dual-in-line package.
·【英文題名】 Research of Speed Regulate System of Three Phase BLDCM Based on DSP 【作者中文名】 劉桂芬; 【導師】 孟慶春; 【學位授予單位】 遼寧工程技術大學; 【學科專業名稱】 控制理論與控制工程 【學位年度】 2007 【論文級別】 碩士 【網絡出版投稿人】 遼寧工程技術大學 【網絡出版投稿時間】 2006-01-02 【
Abstract: Transimpedance amplifiers (TIAs) are widely used to translate the current output of sensors like photodiode-to-voltagesignals, since several circuits and instruments can only accept voltage input. An operational amplifier with a feedback resistor fromoutput to the inverting input is the most straightforward implementation of such a TIA. However, even this simple TIA circuit requirescareful trade-offs among noise gain, offset voltage, bandwidth, and stability. Clearly stability in a TIA is essential for good, reliableperformance. This application note explains the empirical calculations for assessing stability and then shows how to fine-tune theselection of the feedback phase-compensation capacitor.
Control systems are becoming increasingly dependent on digital processing and so require sensors able to provide direct digital inputs. Sensors based on time measurement, having outputs based on a frequency or phase, have an advantage over conventional analogue sensors in that their outputs can be measured directly in digital systems by pulse counting.
Highlights the LTC1062 as a lowpass filter in a phase lock loop. Describes how the loop's bandwidth can be increased and the VCO output jitter reduced when the LTC1062 is the loop filter. Compares it with a passive RC loop filter. Also discussed is the use of LTC1062 as simple bandpass and bandstop filter.