UPS equipment, like majority of static converters takes energy from an AC network through rectifiers. Typically, rectifiers are equipped with thyristors which generate harmonics. This course highlights the need for a standardized coexistence between polluting and polluted equipment. Also course elaborates which harmonic currents and voltages are generated by conventional (classic) rectifiers (thyristor Graetz bridge rectifier) and provides different solutions that are designed to minimize harmonic impact. This course is suitable for electrical engineers who want to understand how UPS equipment affects the overall power quality, particularly current and voltage harmonics. Presented details describe Thyristor Graetz bridge rectifier, harmonic currents generated by a Graetz bridge rectifier, use of double bridge rectifier, rectifier with more than two bridges, utilization of a passive harmonic filters etc. Upon successful completion engineers will have better understanding of different UPS configurations and how they affect overall harmonic profile.

Learning Objectives:

• Thyristor Graetz bridge rectifier
• Harmonic currents generated by a Graetz bridge rectifier
• Minimisation of harmonic disturbances
• Use of double bridge rectifier
• Rectifier circuit with more than two bridges
• Special case of circuit connection called «phase shifting»
• Utilization of a passive filter for harmonics