Abstract: The present invention discloses a power conversion circuit. A control module controls a pulse width modulation regulator to regulate a duty cycle of a DC-DC converter according to the direct current link voltage of the DC-DC converter and the output current and voltage of a renewable power supply. The control module also controls the pulse width modulation regulator to regulate a duty cycle of a DC-AC inverter according to the direct current link voltage of the DC-DC converter, output voltage of a utility power supply, and the output current and voltage of the renewable power supply.

Abstract: A system of a plurality of series-connected fuel cell converter devices and a method for controlling the system are provided. The system includes a plurality of fuel cell converter devices, a series connection unit, a power control unit, a Mux control unit, and a master controller. The output ends of a plurality of fuel cell converter devices are connected in series by the series connection unit. The master controller reads signals from the power control unit and the Mux control unit and determines accordingly which fuel cell converter devices need to be turned on to meet the requirement of a load. The method includes the steps of estimating a load, determining the number of the fuel cell converter devices to be turned on, calculating an output power, discharging, and charging. Thus, a plurality of fuel cell converter devices is controlled to output the required power of the load.

Abstract: A system of a plurality of parallel-connected fuel cell converter devices and a method for controlling the system are provided. The system includes a plurality of fuel cell converter devices, a parallel connection unit, a power control unit, a Mux control unit, and a master controller. The output ends of the plurality of fuel cell converter devices are connected in parallel by the parallel connection unit. The master controller reads signals from the power control unit and the Mux control unit and determines accordingly which fuel cell converter devices need to be turned on to meet the requirement of a load. The method includes the steps of estimating a load, determining the number of the fuel cell converter devices to be turned on, calculating an output power, discharging, and charging. Thus, the plurality of fuel cell converter devices is controlled to output the required power of the load.

Abstract: A linear modulation voltage transformer circuitry includes a power stage unit, a voltage division unit, a linear modulation unit, an error amplifier, and a recursive controller. The power stage unit adapts an input voltage and outputs a first voltage to the voltage division unit, which outputs a divided voltage. The linear modulation unit receives the divided voltage, compares it with a control voltage, and outputs an error voltage signal to the error amplifier, which amplifies the error voltage signal as an error gain control signal. The recursive controller receives and modulates the error gain control signal and outputs the modulation error gain control signal to the power stage unit as a reference signal so as for the power stage unit to modulate the first voltage. Thus, the first voltage can be varied in real time via the linear modulation unit to meet load demands.

Abstract: The present invention discloses a power conversion circuit. A control module controls a pulse width modulation regulator to regulate a duty cycle of a DC-DC converter according to the direct current link voltage of the DC-DC converter and the output current and voltage of a renewable power supply. The control module also controls the pulse width modulation regulator to regulate a duty cycle of a DC-AC inverter according to the direct current link voltage of the DC-DC converter, output voltage of a utility power supply, and the output current and voltage of the renewable power supply.

Abstract: A power supply system and a fuel cell backup power system thereof are provided. The power supply system includes: a mains power supply module for providing mains electricity to a load, and a fuel cell backup power system for providing electricity to the load while the mains electricity provided by the mains power supply module is insufficient. The fuel cell backup power system includes a fuel cell system, a power conditioning module, a battery, and a controller. The fuel cell system and the battery output first and second electrical energy, respectively. The controller defines a plurality of output power requirement levels for the fuel cell system, reads the power required by the load, and adjusts the output ratio between the first and the second electrical energy in a stepwise manner according to the output power requirement levels so as to meet the power required by the load.

Abstract: A system of a plurality of parallel-connected fuel cell converter devices and a method for controlling the system are provided. The system includes a plurality of fuel cell converter devices, a parallel connection unit, a power control unit, a Mux control unit, and a master controller. The output ends of the plurality of fuel cell converter devices are connected in parallel by the parallel connection unit. The master controller reads signals from the power control unit and the Mux control unit and determines accordingly which fuel cell converter devices need to be turned on to meet the requirement of a load. The method includes the steps of estimating a load, determining the number of the fuel cell converter devices to be turned on, calculating an output power, discharging, and charging. Thus, the plurality of fuel cell converter devices is controlled to output the required power of the load.

Abstract: A system of a plurality of series-connected fuel cell converter devices and a method for controlling the system are provided. The system includes a plurality of fuel cell converter devices, a series connection unit, a power control unit, a Mux control unit, and a master controller. The output ends of a plurality of fuel cell converter devices are connected in series by the series connection unit. The master controller reads signals from the power control unit and the Mux control unit and determines accordingly which fuel cell converter devices need to be turned on to meet the requirement of a load. The method includes the steps of estimating a load, determining the number of the fuel cell converter devices to be turned on, calculating an output power, discharging, and charging. Thus, a plurality of fuel cell converter devices is controlled to output the required power of the load.

Abstract: A system of a plurality of series-connected converter devices for a fuel cell apparatus and a method for controlling the system are provided. The system includes a fuel cell apparatus controller, the plurality of converter devices, a series connection unit, a Mux control unit, a power control unit, and a master controller. The output ends of the plurality of converter devices are connected in series by the series connection unit. The master controller reads signals from the power control unit and the Mux control unit and determines accordingly which converter devices need to be turned on to meet the requirement of a load. The method includes the steps of estimating a load, determining the number of the converter devices to be turned on, calculating an output power, discharging, and charging. Thus, the plurality of converter devices is controlled to output the required power of the load.

Abstract: A linear modulation voltage transformer circuitry includes a power stage unit, a voltage division unit, a linear modulation unit, an error amplifier, and a recursive controller. The power stage unit adapts an input voltage and outputs a first voltage to the voltage division unit, which outputs a divided voltage. The linear modulation unit receives the divided voltage, compares it with a control voltage, and outputs an error voltage signal to the error amplifier, which amplifies the error voltage signal as an error gain control signal. The recursive controller receives and modulates the error gain control signal and outputs the modulation error gain control signal to the power stage unit as a reference signal so as for the power stage unit to modulate the first voltage. Thus, the first voltage can be varied in real time via the linear modulation unit to meet load demands.

Abstract: The present invention discloses a random controlled fuel cell power module. The random controlled fuel cell power module includes a power module system, a current detection unit, and a random control unit. The power module system is composed of at least two parallel-connected DC/DC converters, for providing the power for a load. The current detection unit detects a load current value of the load. The random control unit reads the load current value and randomly assigns a control mode to activate the DC/DC converters according to the load current value, so that the DC/DC converters can be equally used. Therefore, the failure rate of the DC/DC converters is reduced, the life of the power module system is relatively prolonged, and the stability of the power module system is simultaneously increased.