# US 10,312,797 B1 · Zero power startup circuit for vibrational energy harvesting > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,312,797 B1 - Document ID: US10312797B1 - Status: Granted - Kind: B1 - Application number: 15/250,299 - Filed: 2016-08-29 - Granted: 2019-06-04 - Earliest claimed: 2016-08-29 - Assignees: The United States of America as represented by the Secretary of the Navy - Applicants: SPAWAR Systems Center Pacific - Inventors: Alex G. Phipps; Eric G. Bozeman - Web page: https://patentgrep.com/patent/US10312797B1 ## CPC - H02J 7/02: for charging batteries from AC mains by converters - H02J 7/00: Circuit arrangements for charging or discharging batteries or for supplying loads from batteries - H02M 1/36: Means for starting or stopping converters - H02M 3/158: including plural semiconductor devices as final control devices for a single load - H02J 2207/20: Charging or discharging characterised by the power electronics converter - H02M 1/0006: {Arrangements for supplying an adequate voltage to the control circuit of converters} - H02M 1/0032: {Control circuits allowing low power mode operation, e.g. in standby mode} - H02M 1/007: {Plural converter units in cascade (push-pull DC/DC converters with pre-regulator H02M3/3374; DC-AC converters following a DC-DC stage including a high frequency transformer H02M7/4807; DC-AC converters following a DC-DC conversion stage generating periodically varying voltages H02M7/4826)} - Y02B 70/10: Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - H02M: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF (transformers H01F; dynamo-electric converters H02K47/00; controlling transformers, reactors or choke coils, control or regulation of electric motors, generators or dynamo-electric converters H02P) - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS ## Abstract An energy harvesting system includes a transducer, a capacitor, a power converter, a power converter control line, a control switch and a control switch control line. The transducer harvests energy and outputs electrical current based on the harvested energy. The capacitor stores a rectified voltage based on the electrical current. The control switch can be open or closed. The control switch control line is arranged to provide a control voltage based on the rectified voltage to the control switch. When the control voltage is equal to or greater than a threshold voltage the control switch is closed such that the power converter control line electrically connects the power converter to a battery in order to provide harvested energy to the battery. ## Claims ### Claim 1 An energy harvesting system for preventing unwanted battery drain, said energy harvesting system comprising: a transducer; a capacitor; a power converter; a power converter control line; a control switch, the control switch comprising one of: a metal oxide semiconductor field effect transistor having a gate tied to rectified DC voltage from a rectifier and a source/drain, the source/drain configured to couple with a battery and the power converter; and an electromechanical relay having a terminal tied to the rectified DC voltage from the rectifier and another terminal coupled with one of ground and a bipolar junction transistor; and a control switch control line, wherein said control switch control line is arranged to provide a control voltage, based on a rectified voltage, to said control switch, wherein, when the control voltage is less than a predetermined threshold voltage, said control switch is operable in an open state, wherein said power converter control line decouples from said power converter, and wherein said power converter deactivates. ### Claim 2 (depends on 1) The system of claim 1, further comprising a rectifier disposed between said transducer and said capacitor. ### Claim 3 (depends on 2) The system of claim 2, wherein said transducer comprises at least one of a group consisting essentially of a piezoelectric transducer, an optoelectronic transducer, a magnetoelectric transducer, a bioelectric transducer, and a thermoelectric transducer. ### Claim 4 (depends on 3) The system of claim 3, wherein said transducer comprises a piezoelectric transducer, and wherein said rectifier comprises a full wave rectifier. ### Claim 5 (depends on 1) The system of claim 1, further comprising an impedance element disposed on said control switch control line. ### Claim 6 (depends on 5) The system of claim 5, further comprising an impedance control device coupled with at least one of a group consisting essentially of said capacitor and said impedance element. ### Claim 7 (depends on 6) The system of claim 6, wherein said impedance element comprises an adjustable resistor, and wherein said impedance control device is coupled with said adjustable resistor and is operable for adjusting resistance of said adjustable resistor to adjust the threshold voltage. ### Claim 8 (depends on 6) The system of claim 6, wherein said capacitor comprises an adjustable capacitor, and wherein said impedance control device is coupled with said adjustable capacitor and is operable for adjusting capacitance of said adjustable capacitor to adjust the threshold voltage. ### Claim 9 (depends on 6) The system of claim 6, wherein said impedance element comprises an adjustable resistor, wherein said capacitor comprises an adjustable capacitor, and wherein said impedance control device is coupled with said adjustable resistor, is coupled with said adjustable capacitor, is operable for adjusting resistance of said adjustable resistor, and is operable for adjusting capacitance of said adjustable capacitor to adjust the threshold voltage. ### Claim 10 An energy harvesting system for preventing unwanted battery drain, comprising: a transducer operable to harvest energy and to output an electrical current based on the harvested energy; a capacitor operable to store a rectified voltage based on the electrical current provided by the transducer; a power converter; a power converter control line; a control switch operable to be in one of an open state and a closed state, the control switch comprising one of: a metal oxide semiconductor field effect transistor having a gate tied to rectified DC voltage from a rectifier and a source/drain, the source/drain configured to couple with a battery and the power converter; and an electromechanical relay having a terminal tied to the rectified DC voltage from the rectifier and another terminal coupled with one of ground and a bipolar junction transistor; a battery; and a control switch control line, wherein said control switch control line is arranged to provide a control voltage, based on the rectified voltage, to said control switch, wherein, when the control voltage is less than a threshold voltage, said control switch is in an open state, and wherein said power converter control line decouples from said power converter. ### Claim 11 (depends on 10) The system of claim 10, further comprising a rectifier disposed between said transducer and said capacitor. ### Claim 12 (depends on 11) The system of claim 11, wherein said transducer comprises at least one of a group consisting essentially of a piezoelectric transducer, an optoelectronic transducer, a magnetoelectric transducer, a bioelectric transducer, and a thermoelectric transducer. ### Claim 13 (depends on 12) The system of claim 12, wherein said transducer comprises a piezoelectric transducer, and wherein said rectifier comprises a full wave rectifier. ### Claim 14 (depends on 10) The system of claim 10, further comprising an impedance element disposed on said control switch control line. ### Claim 15 (depends on 14) The system of claim 14, further comprising an impedance control device in connection with at least one of a group consisting essentially of said capacitor and said impedance element. ### Claim 16 (depends on 15) The system of claim 15, wherein said impedance element comprises an adjustable resistor, and wherein said impedance control device is coupled with said adjustable resistor and is operable for adjusting resistance of said adjustable resistor to adjust the threshold voltage. ### Claim 17 (depends on 15) The system of claim 15, wherein said capacitor comprises an adjustable capacitor, and wherein said impedance control device is coupled with said adjustable capacitor and is operable for adjusting capacitance of said adjustable capacitor to adjust the threshold voltage. ### Claim 18 A method of using an energy harvesting system for preventing unwanted battery drain, the system comprising a transducer, a capacitor, a power converter, a power converter control line, a control switch operable in one of an open state and a closed state, a battery, and a control switch control line, said method comprising: harvesting, via the transducer, energy, thereby providing harvested energy; outputting, via the transducer, electrical current based on the harvested energy; storing, via the capacitor, a rectified voltage based on the electrical current; providing, via the control switch control line, a control voltage, based on the rectified voltage, to said control switch, providing the control switch comprising providing one of: a metal oxide semiconductor field effect transistor having a gate tied to rectified DC voltage from a rectifier and a source/drain, the source/drain configured to couple with a battery and the power converter; and an electromechanical relay having a terminal tied to the rectified DC voltage from the rectifier and another terminal coupled with one of ground and a bipolar junction transistor; when the control voltage is less than a predetermined threshold voltage, placing the control switch in an open state, wherein the power converter control line decouples from the power converter, and wherein the power converter deactivates; and when the control voltage is equal to or greater than then instantaneous threshold voltage, placing the control switch in a closed state, wherein the power converter control line couples with the power converter, wherein the power converter receives an operating signal from the battery, and wherein the power converter outputs converted energy, based on the control voltage, to the battery.