Control circuit having extended hold-up time and conversion system having extended hold-up time

A conversion system having extended hold-up time comprising:

• a conversion circuit comprising:
• a first stage conversion unit configured to convert an input power source into a bus voltage, and
• a second stage conversion unit coupled to the first stage conversion unit through a bus path, and configured to convert the bus voltage into an output power source, and
• a control circuit coupled to the bus path, and comprising:
• a bypass circuit coupled to a live wire end of the bus path,
• an energy storage capacitor having a first end and a second end, the first end coupled to the bypass circuit and the second end coupled to a ground wire end of the bus path, and
• an auxiliary power circuit coupled to the bypass circuit and the conversion circuit, the auxiliary power circuit comprising a conversion unit coupled to the conversion circuit, a voltage regulation circuit coupled to the conversion unit, a charging path coupled to the voltage regulation circuit, the energy storage capacitor, and the bypass circuit, and a voltage regulation unit coupled to the voltage regulation circuit, the charging path, and the energy storage capacitor,
• wherein the auxiliary power circuit is configured to provide an energy storage voltage to the energy storage capacitor according to a working voltage provided by the conversion circuit;
• when the bus voltage of the bus path is less than or equal to the energy storage voltage, the energy storage voltage is provided to the bus path through bypass circuit so that the bus voltage is greater than or equal to a predetermined voltage within a hold-up time,
• wherein when the conversion unit is configured to convert the working voltage into an auxiliary voltage, the voltage regulation circuit is configured to generate a regulation voltage according to the auxiliary voltage;
• the charging path is turned on by the regulation voltage and the energy storage capacitor is charged by the regulation voltage through the charging path so that the energy storage capacitor is configured to establish the energy storage voltage;
• when the bus voltage is less or equal to the energy storage voltage, the energy storage voltage is provided to the bus path through the bypass circuit, and
• wherein the voltage regulation unit is configured to limit a gate voltage of the charging path to be less than or equal to a rated voltage.