Abstract2.1 Introduction2.2 Voltage control—D.C. output from d.c. supply2.3 D.C. from a.c.—Controlled rectification2.4 A.C. from d.c.—Inversion2.5 A.C. from a.c.2.6 Inverter switching devices2.7 Converter waveforms, acoustic noise, and cooling2.8 Review questions