Abstract: A three-phase uninterruptible power system and an operation method thereof are provided. The three-phase uninterruptible power system comprises a DC bus, three power conversion circuits and a control circuit. When the three-phase uninterruptible power system enters a line mode from a battery mode, the control circuit performs a huge current suppression for each power conversion circuit according to a predetermined sequence. The huge current suppression performed for any of the power conversion circuits comprises the following steps: disabling the DC-DC conversion of the power conversion circuit, and having the other two power conversion circuits to additionally share the original load of the disabled power conversion circuit; and after the DC-DC conversion of the power conversion circuit is disabled, enabling the AC-DC conversion of the power conversion circuit, and having the power conversion circuits revert to their original load.

Abstract: A three-phase uninterruptible power system and an operation method thereof are provided. The three-phase uninterruptible power system comprises a DC bus, three power conversion circuits and a control circuit. When the three-phase uninterruptible power system enters a line mode from a battery mode, the control circuit performs a huge current suppression for each power conversion circuit according to a predetermined sequence. The huge current suppression performed for any of the power conversion circuits comprises the following steps: disabling the DC-DC conversion of the power conversion circuit, and having the other two power conversion circuits to additionally share the original load of the disabled power conversion circuit; and after the DC-DC conversion of the power conversion circuit is disabled, enabling the AC-DC conversion of the power conversion circuit, and having the power conversion circuits revert to their original load.

Abstract: A photovoltaic (PV) system is disclosed that provides dynamic regulation of the output of a PV array such that the inverter can safely operate without entering a voltage protection mode. The PV system includes a PV array that generates a direct current (DC) output from received solar radiation and a DC link coupled to the PV array to receive the DC output therefrom. The PV system also includes a DC-to-AC power inverter electrically coupled to the DC link to receive the DC output therefrom and invert the DC output to an AC output and a damping circuit electrically coupled to the DC link and positioned between the PV array and the DC-to-AC power inverter. The damping circuit includes a damping resistor and a damping switch.

Abstract: A photovoltaic (PV) system is disclosed that provides dynamic regulation of the output of a PV array such that the inverter can safely operate without entering a voltage protection mode. The PV system includes a PV array that generates a direct current (DC) output from received solar radiation and a DC link coupled to the PV array to receive the DC output therefrom. The PV system also includes a DC-to-AC power inverter electrically coupled to the DC link to receive the DC output therefrom and invert the DC output to an AC output and a damping circuit electrically coupled to the DC link and positioned between the PV array and the DC-to-AC power inverter. The damping circuit includes a damping resistor and a damping switch.

Abstract: The present invention discloses an aqueous coating composition, comprising: (A) a water-soluble resin and (B) a cross-linking agent. The water-soluble resin after amination is evenly dispersed in a water-soluble solvent and the water-soluble resin is selected from the group consisting of the following or combination thereof: acrylic resin, alkyd resin, epoxy resin, polyurethane resin and polyester resin. The cross-linking agent at least has the function of promoting the reaction and enhancing the interaction force between the water-solution resin and a coating substrate. The function of the cross-linking agent is to have the water-soluble resin be dried naturally or compulsorily.

Abstract: The present invention discloses a method of making the luminous tapeline comprising: forming a primer paint layer on a steel material, forming a scale ink layer on the primer paint layer, forming a protection layer on the scale ink layer. The tapeline can be made luminous through one of the following methods, or any combination thereof: transferring and painting a luminous ink on the primer paint layer, spaying a luminous powder on the primer paint layer, and spaying a luminous powder on protection layer.