AC-to-AC converter having higher output frequency

An AC-to-AC converter comprising:

• input terminals for connection to a power supply, the power supply supplying an alternating input voltage;
• pairs of output terminals, each pair of output terminals for connection to a respective load;
• a plurality of bridge arms connected in parallel to the input terminals, the plurality of bridge arms comprising a respective bridge arm for each pair of output terminals and a common bridge arm;
• and
• a control unit,
• wherein:
• each bridge arm comprises a pair of switches and a node located between the switches;
• each pair of output terminals comprises a first output terminal connected to the node of the respective bridge arm, and a second output terminal connected to the node of the common bridge arm;
• the switches have a plurality of configurations for selectively connecting the output terminals to the input terminals in one of a plurality of arrangements, each configuration comprising a first switching state in which a positive voltage is applied to the output terminals and a second switching state in which a negative voltage is applied to the output terminals;
• the control unit is operable to control the switches to apply an alternating output voltage to the output terminals, the output voltage having a frequency higher than a frequency of the input voltage;
• and
• in at least one setting, the control unit is operable to control the switches such that, over each half-cycle of the input voltage, the switches transition between different configurations.