Download Single Phase Compressor Point-on

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Single Phase Compressor
Point-on-Wave Response
Including tests done at BPA
Bernie Lesieutre (UW-Madison, LBNL)
Dmitry Kosterev Steve Yang Erik Lane
(BPA)
WECC Load Modeling Task Force, June 17, 2015, Salt Lake City
Lesieutre acknowledges support from CERTS and PSERC
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Single Phase Compressor Simulation Model
Tmech
Tave
0
0.25
1.0
mechanical revolution
0.5
0.75
Reciprocating Compressor Mechanical Load
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Current Research: Point-on-Wave Effects
Simulations of Single-Phase Compressor Motor
Applied voltage. The disturbance occurs
at different points along the sinusoid:
peak, zero crossing, in between.
Instantaneous drop to 62% nominal for 3
cycles.
Speed for the different applied voltages.
Worst case: zero crossing disturbance.
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Current Research: Point-on-Wave Effects
Stall Voltage vs fault duration,
and point-on-wave variation.
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Current Research: Point-on-Wave Effects
• Ramp Voltage Instead:
Performance Model Characteristic for
reference
Point-on-wave effect is greatly
reduced for even a very short ramp.
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Current Research: Point-on-Wave Effects
• These results suggest a reason why FIDVR
events don’t cascade.
• Locally, A/C motors stall in response to event.
Further away, the filtered
voltage exceeds threshold.
Performance Model Characteristic for
reference
Point-on-wave effect is greatly
reduced for even a very short ramp.
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Laboratory Tests
• Air Conditioner Tests at BPA Facility
• Test Point-on-Wave Response, with and
without ramp.
• Scroll Compressor
Voltage dip to 48, 45, 40, 35 and 30% nominal
Recovery voltage at 90% nominal.
Find fault duration to result in a change in
operating characteristic (not stall)
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Fault Regions, Instantaneous Voltage Dip
Zero Crossing
Peak
45°
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Fault Region: 1 Cycle Ramp in Voltage Dip
45°
Peak
Zero Crossing
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Key Point
A slight ramp in the voltage disturbance
characteristic greatly decreases the propensity
to stall or abnormal operation.
This may be a contributing factor to why FIDVR
events appear to be localized.
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Scroll Compressor: Three Operating States
1. Normal
2. Stall (Rotor stopped)
3. Single Winding Equivalent Mode?
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Scroll Compressor: Three Operating States
Normal
Abnormal
Vmain
242.6 / 0 °
242.2 / 0 °
Vaux
381.0 / 87.1 °
328.3 / -103.9 °
Imain
13.7 / -47.3 °
29.6 / -24.4 °
Iaux
7.9 / 30.0 °
8.3 / 134.3 °
Itotal
19.1 / -21.1 °
23.7 / -17.5 °
1. Normal
2. Stall (Rotor stopped)
3. Single Winding Equivalent Mode?
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Scroll Compressor: Abnormal Operation
2.2 KW
1.6 KW
Normal Power Flow
5.1 KW
6.5 KW
1.4 KW
3.8 KW
Abnormal Power Flow
Inefficient circulating power flow?
25% higher total energy use.
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Active Power after a Fault