Sine PWM, three-phase and one
10 parts
SPWM3 compares three 500 Hz sine references, 120° apart, against one shared 20 kHz triangle and emits the six unipolar 0/5 V gate patterns of a three-phase inverter — the three P outputs are loaded here, their complements left open. Identical RC filters a decade under the carrier strip the switching and recover three clean sines: measured 1.81 V of 500 Hz fundamental each, spaced 120.0° and 240.0° apart. The single-phase SPWM source below runs the same sine-triangle comparison bipolar, ±5 V. Behavioural switching sources: ideal zero-impedance voltage branches with ideal edges, not transistor bridges.
- SPWM31 500Hz/20kHz 3φ
- R1 1kΩ
- C1 150nF
- R2 1kΩ
- C2 150nF
- R3 1kΩ
- C3 150nF
- SPWM1 500Hz/20kHz
- R4 1kΩ
- C4 150nF
