Dual power switching system and method of operating the same

A dual power switching system configured to select a first power source or a second power source to supply power to a load coupled to an inductive device, the dual power switching system comprising:

• a first static transfer switch coupled to the first power source and the inductive device, and the first static transfer switch comprising a first thyristor and a second thyristor connected in reverse parallel,
• a second static transfer switch coupled to the second power source and the inductive device, and the second static transfer switch comprising a third thyristor and a fourth thyristor, wherein a forward-biased direction of the first thyristor is identical to a forward-biased direction of the fourth thyristor, and
• a controller configured to selectively control the first thyristor, the second thyristor, the third thyristor, and the fourth thyristor according to the first power source or the second power source being as a power-supplying source,
• wherein when the power-supplying source is switched from the first power source to the second power source, the controller is configured to turn off the first thyristor and the second thyristor, and determine whether a commutable time is reached according to a power parameter of the first static transfer switch and the second static transfer switch,
• wherein the controller is configured to calculate a total magnetic flux according to a current magnetic flux of the inductive device and an expected magnetic flux of the second power source, and when the commutable time is reached, the controller is configured to correspondingly turn on at least one of the third thyristor and the fourth thyristor according to the total magnetic flux being less than a threshold.