# US 11,994,413 B2 · Device for exciting a resolver, and resolver arrangement > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,994,413 B2 - Document ID: US11994413B2 - Status: Granted - Kind: B2 - Application number: 17/312,915 - Filed: 2019-11-06 - Published: 2022-02-10 - Granted: 2024-05-28 - Earliest claimed: 2018-12-10 - Assignees: Robert Bosch GmbH - Applicants: Robert Bosch GmbH - Inventors: Tim Bruckhaus - Web page: https://patentgrep.com/patent/US11994413B2 ## CPC - G01D 5/2086: {by movement of two or more coils with respect to two or more other coils} - H03M 1/485: {for position encoding, e.g. using resolvers or synchros} - G01D 3/08: with provision for safeguarding the apparatus, e.g. against abnormal operation, against breakdown - G01D 5/204: {by influencing the mutual induction between two or more coils (G01D5/22 takes precedence)} - G01R 31/346: {Testing of armature or field windings} - G01D: MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR - 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) - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) ## Abstract The present invention relates to providing an electrical voltage for exciting an excitation coil of a resolver (2). In this case, the electrical voltage for exciting the excitation coil of the resolver (2) can be generated by means of pulse-width-modulated driving of at least one half-bridge (H1). In this case, the switching elements of the half-bridge (H1) are fully turned on, with the result that losses such as occur during linear operation of semiconductor switches, for example, can be avoided. If appropriate, the voltage (U_e) provided by the half-bridge (H1) can be additionally increased by means of suitable resonant circuits (L1, C1, C3 . . . ). ## Claims ### Claim 1 A device (1) for exciting a resolver (2): a first output connection (A1) configured to be coupled to a first excitation connection of the resolver (2), a second output connection (A2) configured to be coupled to a second excitation connection of the resolver (2), a first half-bridge (H1) having a first switching element (T1), which is arranged between a supply voltage and a first node (K1), and a second switching element (T2), which is arranged between the first node (K1) and a reference-ground potential, the first node (K1) being coupled to the first output connection (A1), a second half-bridge (H2) having a third switching element (T3), which is arranged between the supply voltage and a second node (K2), and a fourth switching element (T4), which is arranged between the second node (K2) and the reference-ground potential, the second node (K2) being coupled to the second output connection (A2), and a control apparatus (10) configured to control the first switching element (T1), the second switching element (T2), the third switching element (T3), and the fourth switching element (T4), wherein the control apparatus (10) is configured to provide a pulse-width-modulated control signal at each of the control inputs of the switching elements (T1 to T4), and wherein a frequency of the pulse-width-modulated control signal is at least ten times more than that of a fundamental frequency of an excitation voltage provided to the resolver (2). ### Claim 2 (depends on 1) The device (1) as claimed in claim 1, having a first low-pass filter, which is arranged between the first node (K1) and the first output connection (A1). ### Claim 3 (depends on 2) The device (1) as claimed in claim 2, wherein the first low-pass filter comprises a first inductor (L1) and a first capacitor (C1), wherein the first inductor (L1) is connected by a first connection to the first node (K1) of the first half-bridge (H1) and is electrically coupled by a second connection to the first output connection (A1), and the first capacitor (C1) is connected by a first connection to the second connection of the first inductor (L1) and is connected by a second connection to the reference-ground potential. ### Claim 4 (depends on 1) The device (1) as claimed in claim 1, wherein the control apparatus (10) is configured to detect an output voltage (U_e) between the first output connection (A1) and the second output connection (A2), and to control the switching elements (T1 to T4) by using the detected output voltage (U_e). ### Claim 5 (depends on 1) The device (1) as claimed in claim 1, having a second low-pass filter, which is arranged between the second node (K2) and the second output connection (A2). ### Claim 6 (depends on 5) The device (1) as claimed in claim 5, wherein the second low-pass filter comprises a second inductor (L2) and a second capacitor (C2), wherein the second inductor (L2) is connected by a first connection to the second node (K2) of the second half-bridge (H2) and is electrically coupled by a second connection to the second output connection (A2), and the second capacitor (C2) is connected by a first connection to the second connection of the second inductor (L2) and is connected by a second connection to the reference-ground potential. ### Claim 7 (depends on 1) The device (1) as claimed in claim 1, having a first series capacitor (C3), which is arranged between the first node (K1) and the first output connection (A1); and having a second series capacitor (C4), which is arranged between the second node (K2) and the second output connection (A2). ### Claim 8 (depends on 7) The device (1) as claimed in claim 7, wherein the first series capacitor (C3) and the second series capacitor (C4) are designed to form a series resonant circuit with a field coil (E) of a resolver (2), which field coil is connectable between the first output connection (A1) and the second output connection (A2). ### Claim 9 (depends on 1) The device (1) as claimed in claim 1, having a first resistor (R1), which is arranged between the first output connection (A1) and a first voltage potential, and having a second resistor (R2), which is arranged between the second output connection (A2) and a fourth voltage potential. ### Claim 10 (depends on 9) The device as claimed in claim 9, wherein the third voltage potential and the fourth voltage potential are the same. ### Claim 11 A resolver arrangement, having: a resolver (2), comprising a field coil (E) having a first excitation connection and a second excitation connection; and a device (1) for exciting the resolver (2) including a first output connection (A1) configured to be coupled to a first excitation connection of the resolver (2), a second output connection (A2) configured to be coupled to a second excitation connection of the resolver (2), a first half-bridge (H1) having a first switching element (T1), which is arranged between a supply voltage and a first node (K1), and a second switching element (T2), which is arranged between the first node (K1) and a reference-ground potential, the first node (K1) being coupled to the first output connection (A1), a second half-bridge (H2) having a third switching element (T3), which is arranged between the supply voltage and a second node (K2), and a fourth switching element (T4), which is arranged between the second node (K2) and the reference-ground potential, the second node (K2) being coupled to the second output connection (A2), and a control apparatus (10) configured to control the first switching element (T1), the second switching element (T2), the third switching element (T3), and the fourth switching element (T4), wherein the control apparatus (10) is configured to provide a pulse-width-modulated control signal at each of the control inputs of the switching elements (T1 to T4), and wherein a frequency of the pulse-width-modulated control signal is at least ten times than that of a fundamental frequency of an excitation voltage provided to the resolver (2).