Abstract: A circuit system and a circuit control method applied to a motor drive are disclosed. The circuit control method includes the steps of providing a phase-locked circuit unit and providing a PWM control unit. The phase-locked circuit unit enables a first carrier signal and a second carrier signal to have identical amplitudes and starting points. The PWM control unit compares the first carrier signal with a reference signal for controlling a switch. When a load current is independently supplied by at least one DC capacitor, a SVPWM control unit controls an inverter unit for the load current to be zero, thereby reducing DC voltage ripple, operation loss and transient voltage surge.

Abstract: A circuit system and a circuit control method applied to a motor drive are disclosed. The circuit control method includes the steps of providing a phase-locked circuit unit and providing a PWM control unit. The phase-locked circuit unit enables a first carrier signal and a second carrier signal to have identical amplitudes and starting points. The PWM control unit compares the first carrier signal with a reference signal for controlling a switch. When a load current is independently supplied by at least one DC capacitor, a SVPWM control unit controls an inverter unit for the load current to be zero, thereby reducing DC voltage ripple, operation loss and transient voltage surge.

Abstract: A method for manufacturing a smart card includes: planting a solder ball on the secure chip solder pad of the main circuit board; according to the position of the secure chip solder pad on the main circuit board, milling out a groove on the substrate on which the main circuit board is packed, such that the solder ball on the secure chip solder pad is visible at the bottom of the groove; packing the secure chip module into the groove, and by use of the solder ball on the secure chip solder pad, mounting the secure chip module onto the main circuit board. The method is capable of improving the quality of the wiring of the main circuit board; and increasing the scalability of the smart card.

Abstract: An electronic AC power source voltage regulator with the UPS function is provided. The proposed electronic power source voltage regulator includes: an input port, an output, a switch set electrically connected between the input port and an AC power source, a capacitor, an inductor, and an electrical energy converter including an electrical energy storage device, a first output terminal, and a second output terminal. The electrical energy converter of the proposed electronic power source voltage regulator transfers an electrical energy of the electrical energy storage device into the output voltage to be output so as to stabilize the output voltage when a significant voltage difference of the AC power source occurs.

Abstract: A parallel DC-to-AC power inverter system is provided.

Abstract: A parallel power system provides virtual impedance so that the parallel-connected power supplies can couple each other directly and the parallel-connected power supplies have the same real power output by the adjustment of output voltage references. Furthermore, the virtual impedance is greater than an intrinsic impedance of the power supply and thus the virtual impedance is dominant impedance. Therefore, the parallel-connected power supplies can couple each other directly without linking inductors.

Abstract: A DC-to-AC power inverter includes an input port, an output port, a switching circuit, and a system controller. The switching circuit is electrically connected between the input port and the output port responsive to control signals to convert a DC voltage at the input port to an AC output voltage. The system controller senses the AC output voltage at the output port and transforms the AC output voltage to generate a first reference current signal. Furthermore, the system controller senses an output current at the output port to generate an output current signal. Moreover, the system controller senses a reference current signal by adding the first reference current signal to the output current signal. Finally, the system controller generates the control signals responsive to the reference current signal and a sensed inverter current signal by sensing an inverter current at the switching circuit. The related methods are also discussed.

Abstract: The proposed voltage regulator has a power converter, a switch, a transformer, and a switching control device. The power converter is electrically connected to a power source for providing a voltage to compensate the output voltage of the voltage regulator when the output voltage is higher or lower than a predetermined level. The transformer is electrically connected to the switch for being used as a variable voltage source and the connecting configuration of the switch is determined by the input voltage. Also, the switching control device is electrically connected to the power converter for causing the voltage to have a phase shift with the input voltage and the inner product of the voltage and the input current being a positive value. The proposed control method is employed for generating a compensation voltage to stabilize the output voltage of the voltage regulator.

Abstract: An electronic AC power source voltage regulator with the UPS function is provided. The proposed electronic power source voltage regulator includes: an input port, an output, a switch set electrically connected between the input port and an AC power source, a capacitor, an inductor, and an electrical energy converter including an electrical energy storage device, a first output terminal, and a second output terminal. The electrical energy converter of the proposed electronic power source voltage regulator transfers an electrical energy of the electrical energy storage device into the output voltage to be output so as to stabilize the output voltage when a significant voltage difference of the AC power source occurs.

Abstract: A DC-to-AC power inverter includes an input port, an output port, a switching circuit, and a system controller. The switching circuit is electrically connected between the input port and the output port responsive to control signals to convert a DC voltage at the input port to an AC output voltage. The system controller senses the AC output voltage at the output port and transforms the AC output voltage to generate a first reference current signal. Furthermore, the system controller senses an output current at the output port to generate an output current signal. Moreover, the system controller senses a reference current signal by adding the first reference current signal to the output current signal. Finally, the system controller generates the control signals responsive to the reference current signal and a sensed inverter current signal by sensing an inverter current at the switching circuit. The related methods are also discussed.

Abstract: A parallel DC-to-AC power inverter system is provided.

Abstract: A voltage regulator and a control method are provided. The voltage regulator has a power converter, a switch, a transformer, and a switching control device. The power converter is electrically connected to a power source for providing a voltage to compensate the output voltage of the voltage regulator when the output voltage is higher or lower than a predetermined level. The transformer is electrically connected to the switch for being used as a variable voltage source and the connecting configuration of the switch is determined by the input voltage. Also, the switching control device is electrically connected to the power converter for causing the voltage to have a phase shift with the input voltage and the inner product of the voltage and the input current being a positive value. The related control methods are also discussed.