# US 5,703,770 A · Method and apparatus for generating a high voltage > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,703,770 A - Document ID: US5703770A - Status: Granted - Kind: A - Application number: 08/513,027 - Filed: 1995-08-09 - Granted: 1997-12-30 - Earliest claimed: 1994-09-16 - Assignees: Sames S.A. - Inventors: Jean Pierre Burtin; Flavien Dobrowolski; Caryl Thome - Web page: https://patentgrep.com/patent/US5703770A ## CPC - B05B 5/10: Arrangements for supplying power, e.g. charging power (in discharge apparatus B05B5/053) - H02M 3/28: using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC - B05B: SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES (spray-mixers with nozzles B01F25/72; processes for applying liquids or other fluent materials to surfaces by spraying B05D) - 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) ## Abstract A method and apparatus for generating a high voltage by converting input power at a low voltage to output power at a high voltage, by: supplying input power to a low voltage unit to produce a periodic signal having a frequency; supplying the periodic signal to a rectifier voltage multiplier of a specific type to cause the rectifier voltage multiplier to produce the output power at a high voltage, wherein the ratio of output power to input power is a function of the frequency of the periodic signal; identifying the type of the rectifier voltage multiplier; and continually adjusting the frequency of the periodic signal toward a value which maximizes the ratio of output power to input power. ## Claims ### Claim 1 A method for generating a high voltage by converting input power at a low voltage to output power at a high voltage, comprising: supplying input power to a low voltage unit to produce a periodic signal having a frequency; supplying the periodic signal to a rectifier voltage multiplier of a specific type to cause the rectifier voltage multiplier to produce the output power at a high voltage, wherein the ratio of output power to input power is a function of the frequency of the periodic signal; identifying the type of the rectifier voltage multiplier; and continually adjusting the frequency of the periodic signal toward a value which maximizes the ratio of output power to input power. ### Claim 2 A method for generating a high voltage by converting input power at a low voltage to output power at a high voltage, comprising: supplying input power to a low voltage unit to produce a periodic signal having a frequency; supplying the periodic signal to a rectifier voltage multiplier to cause the rectifier voltage multiplier to produce the output power at a high voltage, wherein the ratio of output power to input power is a function of the frequency of the periodic signal; and continually adjusting the frequency of the periodic signal toward a value which maximizes the ratio of output power to input power. ### Claim 3 (depends on 2) A method as defined in claim 2 wherein said step of adjusting comprises supplying to inputs of a calculator signals representing the input power voltage and current and the output power voltage and current and operating the calculator to produce a signal which adjusts the frequency of the periodic signal. ### Claim 4 (depends on 3) A method as defined in claim 3 wherein the calculator is operated to vary the frequency of the periodic signal in increments in a given direction as long as the ratio increases with changes in frequency, and in the opposite direction after the ratio begins to decrease with changes in frequency. ### Claim 5 (depends on 3) A method as defined in claim 3 wherein the voltages and currents represented by signals are DC. ### Claim 6 (depends on 2) A method as defined in claim 2 wherein the high voltage is applied to an electrode of an electrostatic sprayer for a coating product. ### Claim 7 An apparatus for generating a high voltage by converting input power at a low voltage to output power at a high voltage, comprising: a low voltage unit connected to receive the input power to produce a periodic signal having a frequency; a rectifier voltage multiplier connected to receive the periodic signal to cause the rectifier voltage multiplier to produce the output power at a high voltage, wherein the ratio of output power to input power is a function of the frequency of the periodic signal; and means connected for continually adjusting the frequency of the periodic signal toward a value which maximizes the ratio of the output power and the input power. ### Claim 8 (depends on 7) An apparatus as defined in claim 7 wherein said step of adjusting comprises supplying to inputs of a calculator signals representing the input power voltage and current and the output power voltage and current and operating the calculator to produce a signal which adjusts the frequency of the periodic signal. ### Claim 9 (depends on 8) An apparatus as defined in claim 8 wherein the voltages and currents represented by signals are DC. ### Claim 10 (depends on 8) An apparatus as defined in claim 8 wherein the periodic signal is a square wave signal having a waveform selected to minimize first order harmonic content. ### Claim 11 (depends on 10) An apparatus as defined in claim 10 wherein said low voltage unit is controllable to vary the amplitude of the periodic signal. ### Claim 12 (depends on 8) An apparatus as defined in claim 8 wherein said rectifier voltage multiplier has an output for supplying the high voltage power to an electrode and the signal representing output power voltage supplied to said calculator is derived at the rectifier voltage multiplier output. ### Claim 13 (depends on 7) An apparatus as defined in claim 7 wherein said low voltage unit is constructed to function with rectifier voltage multipliers of different types and said apparatus comprises means for identifying the type of said rectifier voltage multiplier. ### Claim 14 (depends on 13) An apparatus as defined in claim 13 wherein said means for identifying determine an initial frequency value for the periodic signal at the start of operation of said apparatus. ### Claim 15 (depends on 13) An apparatus as defined in claim 13 wherein said means for identifying comprise a component for providing an electrical signal representing the type of said rectifier voltage multiplier. ### Claim 16 (depends on 7) An electrostatic sprayer for spraying a coating product, said sprayer comprising a high voltage electrode, in combination with apparatus as defined in claim 7, wherein said rectifier voltage multiplier has an output connected to said electrode. ### Claim 17 A method for generating a high voltage, comprising: producing a periodic signal in a low voltage unit; supplying the periodic signal to a rectifier voltage multiplier of a selected type to cause the rectifier voltage multiplier to produce the high voltage; and identifying the type of the rectifier voltage multiplier. ### Claim 18 (depends on 17) A method as defined in claim 17 wherein said step of identifying comprises producing an electrical signal having a value representative of the type of the rectifier voltage multiplier. ### Claim 19 Apparatus for generating a high voltage, comprising: a low voltage unit for producing a periodic signal; a rectifier voltage multiplier of a selected type connected to receive the low voltage signal to cause the rectifier voltage multiplier to produce the high voltage; and means for identifying the type of the rectifier voltage multiplier. ### Claim 20 (depends on 19) An apparatus as defined in claim 19 wherein said means for identifying comprise a component for providing an electrical signal representing the type of said rectifier voltage multiplier.