# US 10,312,848 B2 · Method for operating an electric machine > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,312,848 B2 - Document ID: US10312848B2 - Status: Granted - Kind: B2 - Application number: 15/535,171 - Filed: 2015-12-10 - Published: 2018-01-18 - Granted: 2019-06-04 - Earliest claimed: 2014-12-12 - Assignees: Audi AG - Applicants: Audi AG - Inventors: Nico Schobeß; Mohamed Hammam - Web page: https://patentgrep.com/patent/US10312848B2 ## CPC - H02P 27/08: with pulse width modulation - H02P 6/15: Controlling commutation time - H02P 23/00: Arrangements or methods for the control of AC motors characterised by a control method other than vector control - H02P 2209/00: Indexing scheme relating to controlling arrangements characterised by the waveform of the supplied voltage or current - H02P: CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS ## Abstract A method for checking an operation of an electric machine, which has three phases. For pulses of a first electric variable of the three phases, a pulse width modulation is carried out. Depending in each case on a positioning of electromechanical components of the electric machine with respect to one another, the first electric variable has a pulse with a longest pulse width for a first of the three phases, a pulse with an intermediate pulse width for a second of the three phases, and a pulse with a shortest pulse width for a third of the three phases. A cycle of the pulse width modulation is delimited by two points in time. ## Claims ### Claim 1 A method for checking an operation of an electric machine having a plurality of electromechanical components, comprising: carrying out a pulse width modulation for a plurality of pulses of a first electric variable having three phases; and measuring at least one value of a second electric variable within at least one measurement window during a cycle of the pulse width modulation, wherein, depending on a positioning of the electromechanical components with respect to one another, the first electric variable has a pulse with a longest pulse width for a first phase of the three phases, a pulse with an intermediate pulse width for a second phase of the three phases, and a pulse with a shortest pulse width for a third phase of the three phases, wherein the cycle of the pulse width modulation is delimited by a first point and a second point in time, wherein the first point in time is at a beginning of the cycle and the second point in time is at an end of the cycle, wherein at least one of the pulses of the three phases is shifted from a first position to a second position with respect to the first point in time such that a beginning of the at least one of the pulses is the first point in time and at least another one of the pulses of the three phases is shifted from a first position to a second position with respect to the second point in time such that an end of the at least another one of the pulses is the second point in time, and wherein the pulse with the longest pulse width is shifted with respect to the first of the two points in time that delimit the cycle, and the pulse with the shortest pulse width is shifted with respect to the second of the two points in time that delimit the cycle. ### Claim 2 (depends on 1) The method according to claim 1, wherein the at least one value of the second electric variable is measured for an intermediate circuit of the electric machine. ### Claim 3 (depends on 1) The method according to claim 1, wherein a point in time that delimits the at least one measurement window is placed on one of the two points in time that delimit the cycle. ### Claim 4 (depends on 1) The method according to claim 1, which is carried out for an electric machine designed as an electric motor. ### Claim 5 (depends on 1) The method according to claim 1, wherein, as the second electric variable, a current flowing through the electric machine is checked, wherein, for a voltage as the first electric variable, two pulses designed as voltage pulses of the three phases respectively are shifted and the current is measured within at least one of these voltage pulses within the at least one measurement window. ### Claim 6 (depends on 1) The method according to claim 1, wherein an operation of the electric machine is checked taking into consideration the at least one measured value. ### Claim 7 A system for checking an operation of an electric machine having a plurality of electromechanical components, comprising: a microcontroller; and at least one sensor, wherein the microcontroller is configured to carry out a pulse width modulation for a plurality of pulses of a first electric variable having three phases, wherein, depending on a positioning of the electromechanical components with respect to one another, the first electric variable has a pulse with a longest pulse width for a first phase of the three phases, a pulse with an intermediate pulse width for a second phase of the three phases, and a pulse with a shortest pulse width for a third phase of the three phases, wherein a cycle of the pulse width modulation is delimited by a first point and a second point in time, wherein the first point in time is at a beginning of the cycle and the second point in time is at an end of the cycle, wherein the microcontroller is configured to shift at least one of the pulses of the three phases from a first position to a second position with respect to the first point in time such that a beginning of the at least one of the pulses is the first point in time, and shift at least another one of the pulses of the three phases from a first position to a second position with respect to the second point in time such that an end of the at least another one of the pulses is the second point in time, wherein the pulse with the longest pulse width is shifted with respect to the first of the two points in time that delimit the cycle, and the pulse with the shortest pulse width is shifted with respect to the second of the two points in time that delimit the cycle, and wherein the at least one sensor is configured to measure at least one value of a second electric variable within at least one measurement window during the cycle of the pulse width modulation. ### Claim 8 (depends on 7) The system according to claim 7, further comprising: a sensor for measurement of the at least one value of the second electric variable. ### Claim 9 (depends on 7) The system according to claim 7, wherein the at least one sensor is designed as a measuring resistor. ### Claim 10 (depends on 7) The system according to claim 7, wherein the microcontroller is designed such that the pulses are to be shifted asynchronously. ### Claim 11 (depends on 1) The method according to claim 1, wherein, in an initial state, the pulse with the intermediate pulse width wholly overlaps the pulse with the longest pulse width, and the pulse with the shortest pulse width wholly overlaps the pulse with the intermediate pulse width. ### Claim 12 (depends on 11) The method according to claim 11, wherein, in a shifted state, the pulse with the intermediate pulse width overlaps with the pulse with the longest pulse width, the pulse with the intermediate pulse width overlaps with the pulse with the shortest pulse width, and the pulse with the longest pulse width is offset from the pulse with the shortest pulse width. ### Claim 13 (depends on 7) The system according to claim 7, wherein, in an initial state, the pulse with the intermediate pulse width wholly overlaps the pulse with the longest pulse width, and the pulse with the shortest pulse width wholly overlaps the pulse with the intermediate pulse width. ### Claim 14 (depends on 13) The system according to claim 13, wherein, in a shifted state, the pulse with the intermediate pulse width overlaps with the pulse with the longest pulse width, the pulse with the intermediate pulse width overlaps with the pulse with the shortest pulse width, and the pulse with the longest pulse width is offset from the pulse with the shortest pulse width.