Performance
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2 ideal diodes, powered from 2 different power supplies, connected to a common DC load. Current measurements were taken with the clamp meter, so are not 100% accurate.
Test Setup:
Test Results:
| Test # | Test Conditions | Test For | PSU 1 V | PSU 1 I | PSU 2 V | PSU 2 I | Load Mode | Load 1 V | Load 1 I | Results |
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Matched PSU Voltage (20V), Current Limit, not hitting CC limit (0.9A each) | 19.98 | 0.7 | 19.99 | 0.6 | CC | 19.85 | 1.4 | Both PSU in CV | |
| 2 | Matched PSU Voltage (20V), Current Limit (0.9A), load at lower CV | Battery Charging | 18.14 | 0.86 | 18.18 | 0.86 | CV | 18 | 1.818 | Both PSU in CC |
| 3 | PSU 1 higher V (21V), PSU 2 20V, Matched Current Limit (0.9A), load at lower CV | Unbalanced V Set Points | 18.14 | 0.87 | 18.18 | 0.87 | CV | 18 | 1.818 | Both PSU in CC |
| 4 | Matched PSU Voltage (20V), PSU 1 higher CC (1.2A), PSU 2 0.9A, load at lower CV | Unbalanced Panels | 18.18 | 1.2 | 18.18 | 0.85 | CV | 18 | 2.125 | Both PSU in CC |
| 5 | Mismatched V and I PSU 1 (22V, 1.2A), PSU 2 (20V, 0.9A), load at lower CV | Unbalanced Panels and Set Points | 18.18 | 1.2 | 18.18 | 0.85 | CV | 18 | 2.123 | Both in CC |
| 6 | PSU1 (22V, 1.2A), PSU2 (20V, 0.9A), Load at CV 19.8V | Batteries charging with mismatched panels and set point | 19.98 | 1.2 | 19.98 | 0.9 | CV | 19.80 | 2.120 | Both PSU in CC |
| 7 | PSU1 (22V, 1.2A), PSU2 (20V, 0.9A), Load at CV 20V | Batteries charging with mismatched panels and set point | 20.18 | 1.2 | 20 | 0 | CV | 20 | 1.22 | PSU 1 in CV, PSU 2 in CC |
| 8 | PSU1 (22V, 1.2A) PSU2 (20V, 0.5A), Load in CC of 0.3A | Single panel can provide the requested current (mismatched voltages) | 21.99 | 0.3 | 20 | 0 | CC | 21.93 | 0.3 | Draws all current from higher voltage panel |
| 9 | PSU1 (20V, 1.2A) PSU2 (20V, 0.5A), Load in CC of 0.3A | Single panel can provide requested current, matched voltages | 19.98 | 0.2 | 19.99 | 0.1 | CC | 19.92 | 0.3 | Uneven load sharing |
| 10 | PSU1 (20V, 1.0A) PSU2 (20V, 0.5A), Load in CC of 0.8A | Single panel (or both panels) can provide requested current, matched voltages | 19.98 | 0.5 | 19.99 | 0.3 | CC | 19.89 | 0.8 | Uneven load sharing |
RESULTS:
Load is shared evenly when the power supplies are in CC mode.
This is best achieved by setting the voltage limit of the power supplies higher than the DC load's CV setting (Tests 2-6).
If one of the PSUs voltages is at or lower than the DC load CV set point, then the power supply transitions to CV mode and outputs nothing.
If the requested current is low, only the higher voltage panel will be providing power, as long as the power is sufficient.
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