Auxiliary power circuit, balance circuit, and power supply system

A balance circuit of a conversion module, an input end of the conversion module comprising an even number of energy storage units coupled in series, and each energy storage unit comprising a first end and a second end, the balance circuit comprising:

• an even number of primary-side circuits, and each primary-side circuit comprising:
• a first switch unit comprising a first end and a second end, and the first end of the first switch unit correspondingly coupled to the first end of one of the energy storage units,
• a second switch unit comprising a first end and a second end, and the first end of the second switch unit coupled to the second end of the first switch unit, and the second end of the second switch unit correspondingly coupled to the second end of one of the energy storage units, and
• a resonance tank coupled in parallel to the second switch unit, and
• a secondary-side circuit comprising:
• a plurality of induction units coupled in parallel to each other, and respectively coupled to the two resonance tanks of the two primary-side circuits,
• wherein the number of the primary-side circuits is at least four.

A power supply system comprising:

• a plurality of conversion modules, each conversion module comprising an input end, and the input ends of the plurality of conversion modules coupled in series, the input end comprising an even number of energy storage units coupled in series, and each energy storage unit comprising a first end and a second end, each conversion module comprising:
• an auxiliary power circuit comprising:
• an even number of primary-side circuits, and each primary-side circuit comprising:
• a first switch unit comprising a first end and a second end, and the first end of the first switch unit correspondingly coupled to the first end of one of the energy storage units,
• a second switch unit comprising a first end and a second end, and the first end of the second switch unit coupled to the second end of the first switch unit, and the second end of the second switch unit correspondingly coupled to the second end of one of the energy storage units, and
• a resonance tank coupled in parallel to the second switch unit, and
• a secondary-side circuit comprising:
• at least one induction unit coupled to the two resonance tanks of the two primary-side circuits, and
• a rectification circuit coupled to the at least one induction unit, and configured to rectify a power provided by the at least one induction unit into a DC power,
• a power stage circuit coupled to the input end, and
• a control unit coupled to the rectification circuit and the power stage circuit, and configured to receive the DC power to operate and to control the power stage circuit.