Patent ID: 11923711
Assignee: AMOGY, INC.
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H | IPC H

Claim 8:
9. A method, comprising:
utilizing a fuel cell to supply power to a load;
in response to an increase in power demand by the load, utilizing a battery to supply power to the load in conjunction with the fuel cell;
in response to a decrease in power demand by the load:
utilizing the fuel cell to supply power to the load;
utilizing the fuel cell to supply charging current to charge the battery toward a target voltage level; and
controlling activation and deactivation of a solid-state switch by an analog control system applying a control signal to a gate terminal of the solid-state switch to modulate the amount of charging current that is supplied to the battery to charge the battery toward the target voltage level, wherein the battery and the solid-state switch are connected in series,
wherein the analog control system comprises:
a voltage monitoring circuit for determining a voltage level of the battery, and generating a first control signal based on the determined voltage level;
a current sensor for sensing magnitude and direction of current flow between the battery and the solid-state switch, and generating a second control signal based on the sensed magnitude and direction of the current flow between the battery and the solid-state switch; and
a switch controller for receiving the first and second control signals, and generating the control signal which comprises a pulse-width modulated control signal with a varying duty cycle, based on the first and second control signals;
wherein the voltage monitoring circuit comprises:
a differential amplifier comprising a first input terminal coupled to a positive terminal of the battery, and a second input terminal coupled to a negative terminal of the battery; and
an operational amplifier comprising a first input terminal coupled to an output of the differential amplifier, and a second input terminal for receiving as input a first threshold voltage;
wherein the operational amplifier compares an output voltage of the differential amplifier with the first threshold voltage and generates the first control signal based on the comparison.