3. Rob Woudenberg
Applied Input / output signals
FEMM input parameters can only be current
Primary current phase (red curve)is fixed
Secondary current phase (blue curve) is changed from 0 to
359 degrees in steps of one degree to find unique situations
Applied current values: 0.2 – 1.2 Amps
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5. Rob Woudenberg
Cop vs phase (2)
04/12/2010Confidential
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At low currents two COP peaks occur over the 180 – 359
range
The lower the current the wider the COP peaks are apart
At higher currents the two COP peaks merge at around 270
degrees
Further fine tuning on current value will give one COP >>
100000 at 270 degrees @ I=1.075 A in this simulation≈
0
5 0
1 0 0
1 5 0
2 0 0
2 5 0
180
184
188
192
196
200
204
208
212
216
220
224
228
232
236
240
244
248
252
256
260
264
268
272
276
280
284
288
292
296
300
304
308
312
316
320
324
328
332
336
340
344
348
352
356
360
0 .2
0 .4
0 .6
0 .8
1
1 .0 5
1 .0 7 5
1 .1
1 .2
6. Rob Woudenberg
Power factor vs phase
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Power factor obtains it’s minimum around the 270 phase
difference area
Power factor can be positive or negative
PF = 0 270 degrees @ I=1.075 A in this simulation≈
7. Rob Woudenberg
Secondary Voltage vs current phase
Load is aimed to be pure resistant.
Phase between V and I of secondary coils is 0 degrees at
270 degrees @ I=1.075 A in this simulation
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-100
-80
-60
-40
-20
0
20
40
60
80
100
184
188
192
196
200
204
208
212
216
220
224
228
232
236
240
244
248
252
256
260
264
268
272
276
280
284
288
292
296
300
304
308
312
316
320
324
328
332
336
340
344
348
352
356
0.2
0.4
0.6
0.8
1
1.05
1.075
1.1
1.2
10. Rob Woudenberg
General observations and conclusions
Unique COP values appear at various input output current phase differences
Some of these COP situations can never happen because of impossible load impedance causing
phase differences > 90 degrees
At 270 degrees input / output phase difference COP > 1 situations occur where voltage
and current phase differences of the secondary coils are zero. This is corresponding a
pure resistive load
The 270 degrees point can be explained as follows:
Polarity of Iin and Iout definitions are 180 degrees different in the circuit model
The additional 90 degrees is cause by the transition of signals from primary to secondary:
Ip→p Vs Is ,current to flux to voltage to current.→ →
The voltage to current occurs in an induction that causes 90 degrees phase difference
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BiTTIin Iout