# US 11,451,183 B2 · Apparatus and method for detecting BLDC motor overload > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,451,183 B2 - Document ID: US11451183B2 - Status: Granted - Kind: B2 - Application number: 16/447,109 - Filed: 2019-06-20 - Published: 2020-05-28 - Granted: 2022-09-20 - Earliest claimed: 2018-11-22 - Assignees: Hyundai Motor Company; Kia Motors Corporation - Applicants: Hyundai Motor Company; Kia Motors Corporation - Inventors: Choong Seob Park - Web page: https://patentgrep.com/patent/US11451183B2 ## CPC - H02K 21/14: with magnets rotating within the armatures - H02P 29/024: Detecting a fault condition, e.g. short circuit, locked rotor, open circuit or loss of load - H02K 7/085: {radially supporting the rotary shaft at only one end of the rotor (H02K7/086, H02K7/09 take precedence)} - H02K 7/14: Structural association with mechanical loads, e.g. with hand-held machine tools or fans (with fan or impeller for cooling the machine H02K9/06) - H02K 11/33: Drive circuits, e.g. power electronics (H02K11/38 takes precedence) - H02K 29/00: Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices - H02P 9/006: {Means for protecting the generator by using control (control effected upon generator excitation circuit to reduce harmful effects of overloads or transients H02P9/10)} - H02P 9/107: {for limiting effects of overloads} - H02P 21/04: specially adapted for very low speeds - H02P 21/14: Estimation or adaptation of machine parameters, e.g. flux, current or voltage - H02P 21/50: {Vector control arrangements or methods not otherwise provided for in H02P21/00- H02P21/36} - H02P 25/02: characterised by the kind of motor - H02P 29/028: the motor continuing operation despite the fault condition, e.g. eliminating, compensating for or remedying the fault - H02P 29/032: Preventing damage to the motor, e.g. setting individual current limits for different drive conditions - H02P 29/10: for preventing overspeed or under speed - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) - H02P: CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS ## Abstract The present disclosure provides a brushless direct current (BLDC) motor overload detection apparatus. The BLDC motor overload detection apparatus includes a measurer for measuring an electrical angle of the BLDC motor, a determiner for determining whether a difference between the electrical angle measured by the measurer and a mechanical angle of the BLDC motor, estimated through current supplied to the BLDC motor, is within a predetermined range, and a driving controller for control of driving of the BLDC motor according to whether the BLDC motor stalls, determined by the determiner. ## Claims ### Claim 1 An apparatus for detecting overload of a brushless direct current (BLDC) motor, comprising: a measurer for measuring an electrical angle of the BLDC motor; a determiner for determining whether a difference between the electrical angle measured by the measurer and a mechanical angle of the BLDC motor, estimated through current supplied to the BLDC motor, is within a predetermined range; and a driving controller for control of driving of the BLDC motor according to whether the BLDC motor stalls, determined by the determiner; wherein the predetermined range is set based on 90 degrees; when the BLDC motor is in a normal condition, the difference between the electrical angle and the mechanical angle is maintained within the predetermined range; and when the BLDC motor is in a stall condition, the difference between the electrical angle and the mechanical angle is out of the predetermined range. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the determiner determines that an error occurs in the BLDC motor when the difference between the electrical angle and the mechanical angle is out of the predetermined range. ### Claim 3 (depends on 2) The apparatus of claim 2, wherein the determiner determines that the BLDC motor stalls when a value obtained by adding a number of times the error occurs to an initialization value is greater than a predetermined threshold value. ### Claim 4 (depends on 2) The apparatus of claim 2, wherein: when the error occurs in the BLDC motor, the determiner counts a number of times the error occurs; and when a value obtained by adding the number of times the error occurs to an initialization value is equal to or less than a predetermined threshold value, the determiner repeatedly determines whether the difference between the electrical angle and the mechanical angle is out of the predetermined range. ### Claim 5 (depends on 4) The apparatus of claim 4, wherein the determiner determines that the number of times the error occurs by subtracting a predetermined number from the initialization value when error does not occur in the BLDC motor. ### Claim 6 (depends on 1) The apparatus of claim 1, wherein, when the determiner determines that the BLDC motor stalls, the driving controller controls a velocity value of the BLDC motor to 0. ### Claim 7 A method of detecting stall of a brushless direct current (BLDC) motor, the method comprising: deriving a mechanical angle of the BLDC motor from a current value supplied to the BLDC motor; measuring an electrical angle of the BLDC motor; determining whether a difference between the mechanical angle and the electrical angle is within a predetermined range; counting a number of times an error, in which the difference between the mechanical angle and the electrical angle is out of the predetermined range, occurs; and determining whether the BLDC motor stalls based on the number of times the error occurs. ### Claim 8 (depends on 7) The method of claim 7, wherein the determining whether the BLDC motor stalls based on the number of times the error occurs includes determining that the BLDC motor stalls when the number of times the error occurs is equal to or greater than a predetermined threshold value. ### Claim 9 (depends on 7) The method of claim 7, wherein the determining whether the difference between the mechanical angle and the electrical angle is within the predetermined range includes: determining that the BLDC motor is in a normal condition when the difference between the mechanical angle and the electrical angle is within the predetermined range, and determining that the BLDC motor is in a stall condition when the difference between the mechanical angle and the electrical angle is out of the predetermined range. ### Claim 10 (depends on 9) The method of claim 9, wherein the counting of the number of times error, in which the difference between the mechanical angle and the electrical angle is out of the predetermined range, occurs includes: subtracting a predetermined number from a previous error value when the BLDC motor is in the normal condition; and adding the predetermined number to the previous error value when the BLDC motor is in the stall condition. ### Claim 11 (depends on 10) The method of claim 10, wherein the determining whether the BLDC motor stalls based on the number of times the error occurs includes determining whether a current error value obtained by adding or subtracting the number of times the error occurs corresponding to a predetermined number to or from the previous error value is equal to or greater than the predetermined threshold value. ### Claim 12 (depends on 11) The method of claim 11, further comprising repeatedly measuring whether the difference between the electrical angle and the mechanical angle is out of the predetermined range when the current error value is equal to or less than the predetermined threshold value. ### Claim 13 (depends on 7) The method of claim 7, further comprising controlling a velocity of the BLDC motor to 0 upon determining that the BLDC motor stalls based on the number of times the error occurs.