Measurement of the DeltaAngle for a Synchronous Machine

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Measurement of the Delta-Angle for a Synchronous
Machine

• Derek Hearn
• Percy Verastegui

ECE 345 Senior Design, Summer 2000
Professor Gary Swenson TA Julio Urbina
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Background

• Reasons why we chose this project

• We both took ECE 333

• Stroboscope Inaccurate

• Long and Tedious

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Objective

• Intended Applications

• Replace the Existing Method

• More Accurate Measurement

• Better Data

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Lab Experiment

• Brief Overview of Lab

• DC Dynamometer acts as a Generator to Synchronous
  Motor

• DC Dynamometer and Synchronous Motor Lock into
  Synchronism

• Add Load to the DC Generator

• Watch the change in Delta-Angle with Stroboscope

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Lab Setup
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Initial Design
Synchronous Machine
Data Process Block TTL design with the 68HC12-
Motorola chip
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Design
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Apparatus

• Mobile

• Inexpensive

• User-Friendly

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Disc

• Connected Via Coupler

• Spins in Synchronism
  
  
• with the shaft

• Max Angle 30 degrees

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Phototransistor Circuit

• Goals

• Light High Dark Low

• Fast Frequency Response

• Obstacles

• Reset Pin from the Counters to the L14F2
  Phototransistor

• Slow Frequency Response for the OPB607A
  Phototransistor

• Solution

• Differential Operational Amplifier

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Counters

• 2 - 74F192 Up/Down Decade Counters

• 7.2 KHz Square Waveform into the Ones Place
  Clock Input

• Carry out of Ones Place to Tens Place Clock
  Input

• Input of Reset Pin is from the Output of the
  Phototransistor

• High Reset Counters to Zero Low Count

• Outputs go to Port A of Motorola Microcontroller

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Motorola Chip

• Using the 68HC912B32 chipset

• Familiar Code

• Bits are easily handled by Accumulators

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Code
INITIALIZE PORTS PORTA EQU 0000 8
IN PORTB EQU 0001 8 OUT PORTDLC EQU
00FE FLAG INITIALIZE REGISTERS DDRA
EQU 0002 DDRB EQU 0003 DDRDLC
EQU 00FF ORG 0800 PROGRAM STARTS HERE
LDAA 00000000 DIRECT PORT A FOR INPUT
STAA 0002 LDAA 11111111 DIRECT
PORT B FOR OUTPUT STAA 0003 LDAA
00000000 DIRECT PORT DLC FOR INPUT
STAA 00FE
BEGIN LOOP LDAB 00FE LOAD PORT DLC
INTO ACCUM B LDAA 00000000 LOAD ACCUM A
WITH ALL ZEROS
CBA COMPARE ACCUM A TO ACCUM B
BMI LOOP BANCH OUT IF ACCUM B HAS A ZERO
LDAA 0000 LOAD ACCUM A WITH CONTENT AT PORT
A STAA 0001 OUTPUT THE CONTENTS IN ACCUM
A TO PORT B
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Code Continued
TIMER START PSHX PUSH X
PSHY PUSH Y LDY
32 LOAD INDEX REG Y WITH HEX 32 (50) LOOPY
LDX 4E1E LOAD INDEX REG X WITH HEX 4E1E
(19998) LOOPX DEX DECREMENT INDEX REG
X BNE LOOPX BRANCH TO LOOPX IF NOT
EQUAL DEY DECREMENT INDEX REG Y
BNE LOOPY BRANCH TO LOOPY IF NOT EQUAL
PULY PULL STACK IN INDEX REG Y
PULX PULL STACK IN INDEX REG X
LDAB 0000 LOAD CONTENTS FROM PORT A
INTO ACCUM B STAB 0001 OUTPUT THE
CONTENTS IN ACCUM B TO PORT B
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Bin/Dec Decoder

• 2- 7442 TTL Chips with 2- MAN72A, 7-Segment
  Displays

• Input From Port B of Motorola Microcontroller

• Converts 4-bit Signal to a 7-bit Signal

• 7-Segment Display Outputs 7-bit Signal as a
  Decimal Number

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Final Comments

• Recommendations

• Replace TTL Counters with CMOS Counters

• Use a Phototransistor with Short Rise/Fall Times

• Replace TTL Counters with CMOS Counters

• Do not use the 68HC912B32 chip Volatile

• Use an Infrared-style Motor Encoder

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THE END

• OR IS IT JUST THE BEGINNING ???