Electrical math
Power calculation
| Quantity | Unit | Name |
|---|---|---|
| P | W | Active power |
| Q | var | Reactive power |
| S | VA | Apparent power |
Power quadrants
| Quadrant | Phase angle φ | Current relative to voltage |
|---|---|---|
| I | 0 to 90° | Lagging |
| II | 90 to 180° | Lagging |
| III | -180 to -90° | Leading |
| IV | -90 to 0° | Leading |
| +P | Import Active Power |
|---|---|
| −P | Export Active Power |
| +Q | Import Reactive Power |
| −Q | Export Reactive Power |