Table 3 Comparison of merits and demerits of modulation techniques
Modulation scheme | Merits | Demerits |
|---|---|---|
Selective harmonic elimination (SHE) | Lower-order harmonics can able to eliminate Harmonics are low Filter size is reduced Suitable for high-power application Efficiency is high Minimum losses during switching operation Steady-state response is better | Slower dynamic response Voltage balancing is ineffective Passive filters requirement is more |
State vector control (SVC) | Effectively works at low switching frequencies Easy technique High efficiency with low harmonics Switching states are less Lesser dv/dt stress Dynamic response is good Huge passive filters not required | Lower harmonics are not eliminated Complex structure |
Phase-shifted PWM (PS-PWM) | Structure is simple and modular Switching pattern rotation is not necessary | Harmonic content is high Voltage balancing is weak Dynamic response is poor |
Phase disposition PWM (PD-PWM) | Voltage profile is best Optimal switching angle is achieved | Power distribution is uneven Dynamic response is poor |