8. 1 Indirect ac to Ac converters (AC-DC-AC converters) Classifications 4 According to type of the dc links Voltage-source type AC-DC-AC converters Current-source type 4 According to whether output voltage and frequency is variable: Variable voltage variable frequency WF AC-DC-AC converters (AC-DC-AC frequency converters) Constant voltage constant frequen (CVCF) 3Power Electron cs i 3 8.1 Indirect AC to AC converters Indirect AC to AC converters (AC -DC -AC converters) AC converters) Classifications Classifications According to type of the DC links: According to type of the DC links: Voltage Voltage -source type source type AC -DC -AC converters AC converters Current Current-source type source type Variable voltage variable frequency Variable voltage variable frequency (VVVF) (AC -DC -AC frequency converters) According to whether output voltage and frequency is According to whether output voltage and frequency is variable: AC -DC -AC converters AC converters AC frequency converters) Constant voltage constant frequency Constant voltage constant frequency (CVCF) variable: