# US 2021/0344282 A1 · Method and apparatus for determining the intermediate circuit current of a converter > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0344282 A1 - Document ID: US20210344282A1 - Status: Published application - Kind: A1 - Application number: 17/302,327 - Filed: 2021-04-30 - Published: 2021-11-04 - Earliest claimed: 2020-05-03 - Assignees: IAV GmbH Ingenieurgesellschaft Auto und Verkehr - Applicants: IAV GmbH Ingenieurgesellschaft Auto und Verkehr - Inventors: Michael HOMANN; Faical TURKI - Web page: https://patentgrep.com/patent/US20210344282A1 ## CPC - G01R 19/0092: {Measuring current only} - H02M 7/53873: {with digital control} - H02M 1/0009: {Devices or circuits for detecting current in a converter} - H02M 1/0012: {Control circuits using digital or numerical techniques (in DC/DC converters H02M3/157, H02M3/33515; in DC-AC converters H02M7/53873)} - H02M 7/5387: in a bridge configuration - H03M 3/458: {Analogue/digital converters using delta-sigma modulation as an intermediate step} - G01R 31/42: AC power supplies - H02M 7/53871: {with automatic control of output voltage or current} - H02M 7/53878: {by time shifting switching signals of one diagonal pair of the bridge with respect to the other diagonal pair} - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) - 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) - H03M: CODING; DECODING; CODE CONVERSION IN GENERAL (using fluidic means F15C4/00; optical analogue/digital converters G02F7/00; coding, decoding or code conversion, specially adapted for particular applications, see the relevant subclasses, e.g. G01D, G01R, G06F, G06T, G09G, G10L, G11B, G11C, H04B, H04L, H04M, H04N; ciphering or deciphering for cryptography or other purposes involving the need for secrecy G09C) ## Abstract An intermediate circuit current of a power converter is determined as precisely as possible in a simple and inexpensive manner. The intermediate circuit current is determined as a function of a detection of the measured output voltages and output currents of the individual phases. ## Claims ### Claim 1 A method for determining an intermediate circuit current of a power converter with switches for converting a direct voltage into an alternating voltage, comprising: measuring output currents of individual phases of the power converter; measuring output voltages of the individual phases of the power converter; determining switching functions of the individual phases that are assigned to the switches of the power converter; determining, based on the measured output voltages, potential changes of the output voltages of the individual phases from negative potential to positive potential and from positive to negative potential; correcting the switching functions of the individual phases as a function of the determined potential changes; and determining the intermediate circuit current as a function of the measured output currents of the individual phases of the power converter and as a function of the corrected switching functions that are assigned to the switches of the power converter. ### Claim 2 (depends on 1) The method according to claim 1, wherein the switching functions are corrected by forming correction variables on the basis of the potential changes, which variables represent switch-on and switch-off delays of the switches along with dead times between the switch-on and switch-off of the switches of a bridge branch of the power converter, and wherein the correction variables are added to the switching functions. ### Claim 3 A method for determining an intermediate circuit current of a power converter with switches for converting a direct voltage into an alternating voltage, comprising: measuring output currents of individual phases of the power converter; measuring output voltages of individual phases of the power converter; determining, based on the measured output voltages, potential changes of the output voltages of the individual phases from negative potential to positive potential and from positive to negative potential; deriving switching functions of the individual phases that are assigned to the switches of the power converter as a function of the determined potential changes; and determining the intermediate circuit current as a function of the measured output currents of the individual phases of the power converter and as a function of the derived switching functions that are assigned to the switches of the power converter. ### Claim 4 (depends on 3) The method according to claim 3, wherein the switching functions are derived as a function of the potential changes in that either constant values=0 or constant values=1 are assigned to the measured output voltages of the individual phases between successive potential changes, depending on whether the potential is negative or positive, such that switching functions, whose function values change over time between the value=0 and the value=1, are provided. ### Claim 5 (depends on 3) The method according to claim 3, wherein the deriving the switching functions is carried out as a function of the potential changes in that the output voltages of the individual phases are measured by delta-sigma analog-to-digital converters and digital bitstreams thus available for the individual phases represent the switching functions as a function of the potential changes, wherein the measured output currents of the individual phases are weighted on the basis of the digital bitstream. ### Claim 6 (depends on 1) The method according to claim 1, wherein the output voltages are measured by delta-sigma analog-to-digital converters. ### Claim 7 (depends on 2) The method according to claim 2, wherein the output voltages are measured by delta-sigma analog-to-digital converters. ### Claim 8 (depends on 1) A device that is configured to carry out the method according to claim 1. ### Claim 9 (depends on 2) A device that is configured to carry out the method according to claim 2. ### Claim 10 (depends on 8) A vehicle comprising the device according to claim 8. ### Claim 11 (depends on 9) A vehicle comprising the device according to claim 9.