# US 12,015,370 B2 · Systems and methods for controlling stepping motor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,015,370 B2 - Document ID: US12015370B2 - Status: Granted - Kind: B2 - Application number: 17/662,849 - Filed: 2022-05-11 - Published: 2022-08-25 - Granted: 2024-06-18 - Earliest claimed: 2019-12-24 - Assignees: Zhejiang Dahua Technology Co., Ltd. - Applicants: Zhejiang Dahua Technology Co., Ltd. - Inventors: Xiaoling Shi; Zengqi Yang; Jianping Li - Web page: https://patentgrep.com/patent/US12015370B2 ## CPC - H02P 8/12: Control or stabilisation of current - H02P 8/32: Reducing overshoot or oscillation, e.g. damping - H02P 8/34: Monitoring operation (H02P8/36 takes precedence) - H02P: CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS ## Abstract The present disclosure relates to systems and methods for controlling a stepping motor. A method may include determining a driving voltage based on a function, wherein the function includes a predetermined electric current and operating parameters of the stepping motor; and driving the stepping motor to work based on the driving voltage via an H-bridge. ## Claims ### Claim 1 A system for controlling a stepping motor, comprising: at least one storage medium including a set of instructions for controlling a stepping motor; and at least one processor in communication with the storage medium, wherein when executing the set of instructions, the at least one processor is directed to perform operations including: determining a driving voltage based on a function, wherein the function includes a predetermined electric current and operating parameters of the stepping motor, and the function includes |U|=√{square root over ((|I|ωL+ω|C|sin γ)2+(|I|R+ω|C|cos γ)2)}, wherein |U|denotes an amplitude of the driving voltage, |I| denotes an amplitude of the predetermined electric current, the predetermined electric current is a sinusoidal current, ωdenotes an angular frequency of the driving voltage, |C| denotes a back electromotive force constant of the stepping motor, L denotes a phase inductance of the stepping motor, γ denotes a load angle of the stepping motor, and R denotes a sum of a phase resistance of the stepping motor and an on-resistance of the H-bridge; and driving the stepping motor to work based on the driving voltage via an H-bridge. ### Claim 2 (depends on 1) The system of claim 1, wherein the operations further include: driving the stepping motor with a first working voltage; obtaining a first working current of the stepping motor under the first working voltage; and determining the back electromotive force constant based on the first working voltage and the first working current. ### Claim 3 (depends on 2) The system of claim 2, wherein the back electromotive force constant is determined according to ❘ "\[LeftBracketingBar]" C ❘ "\[RightBracketingBar]" = 1 ω ⁢ ( ❘ "\[LeftBracketingBar]" U 1 ❘ "\[RightBracketingBar]" ⁢ sin ⁢ ϕ - ❘ "\[LeftBracketingBar]" I 1 ❘ "\[RightBracketingBar]" · ω ⁢ L ) 2 + ( ❘ "\[LeftBracketingBar]" U 1 ❘ "\[RightBracketingBar]" ⁢ cos ⁢ ϕ - ❘ "\[LeftBracketingBar]" I 1 ❘ "\[RightBracketingBar]" · R ) 2 , wherein |C| denotes the back electromotive force constant of the stepping motor, ωdenotes an angular frequency of the first working voltage, |U1| denotes an amplitude of the first working voltage, ϕ denotes a phase of the first working voltage, |11| denotes an amplitude of the first working current, L denotes the phase inductance of the stepping motor, and R denotes the sum of the phase resistance of the stepping motor and the on-resistance of the H-bridge. ### Claim 4 (depends on 1) The system of claim 1, wherein the operations further include: determining the phase resistance of the stepping motor based on an operating environment of the stepping motor. ### Claim 5 (depends on 4) The system of claim 4, wherein the phase resistance of the stepping motor is determined according to R1=R25° C.×(1+(T−25)*0.004), wherein R1 denotes the phase resistance of the stepping motor, R25° C. denotes a phase resistance of the stepping motor when the stepping motor is operated at 25° C., and T denotes a temperature of the operating environment. ### Claim 6 (depends on 1) The system of claim 1, wherein the operations further include: driving the stepping motor with a second working voltage; obtaining a second working current of the stepping motor under the second working voltage; and determining the load angle of the stepping motor based on the second working voltage and the second working current. ### Claim 7 (depends on 6) The system of claim 6, wherein the load angle is determined according to γ = arctan ⁢ ❘ "\[LeftBracketingBar]" U 2 ❘ "\[RightBracketingBar]" ⁢ sin ⁢ ϕ - ❘ "\[LeftBracketingBar]" I 2 ❘ "\[RightBracketingBar]" · ω ⁢ L ❘ "\[LeftBracketingBar]" U 2 ❘ "\[RightBracketingBar]" ⁢ cos ⁢ ϕ - ❘ "\[LeftBracketingBar]" I 2 ❘ "\[RightBracketingBar]" · R , wherein γ denotes the load angle, |U2| denotes an amplitude of the second working voltage, ϕ denotes a phase of the second working voltage, |12|denotes an amplitude of the second working current, ωdenotes an angular frequency of the second working voltage, L denotes the phase inductance of the stepping motor, and R denotes the sum of the phase resistance of the stepping motor and the on-resistance of the H-bridge. ### Claim 8 (depends on 1) The system of claim 1, wherein the operations further include: storing a table indicating a relationship between the driving voltage and the angular frequency. ### Claim 9 (depends on 1) The system of claim 1, wherein the driving the stepping motor to work based on the driving voltage via the H-bridge includes: obtaining pulse width modulation (PMW) signals by inputting an amplitude of the driving voltage to a sinusoidal pulse width modulation (SPWM) generation module; and controlling the H-bridge to drive the stepping motor by inputting the PWM signals to the H-bridge. ### Claim 10 A method for controlling a stepping motor, comprising: determining a driving voltage based on a function, wherein the function includes a predetermined electric current and operating parameters of the stepping motor, and function includes |U|=√{square root over ((|I|ωL+ω|C|sin γ)2+(|I|R+ω|C|cos γ)2)}, wherein |U| denotes an amplitude of the driving voltage, |I| denotes an amplitude of the predetermined electric current, the predetermined electric current is a sinusoidal current, ωdenotes an angular frequency of the driving voltage, |C| denotes a back electromotive force constant of the stepping motor, L denotes a phase inductance of the stepping motor, γ denotes a load angle of the stepping motor, and R denotes a sum of a phase resistance of the stepping motor and an on-resistance of the H-bridge; and driving the stepping motor to work based on the driving voltage via an H-bridge. ### Claim 11 (depends on 10) The method of claim 10, further comprising: driving the stepping motor with a first working voltage; obtaining a first working current of the stepping motor under the first working voltage; and determining the back electromotive force constant based on the first working voltage and the first working current. ### Claim 12 (depends on 11) The method of claim 11, wherein the back electromotive force constant is determined according to ❘ "\[LeftBracketingBar]" C ❘ "\[RightBracketingBar]" = 1 ω ⁢ ( ❘ "\[LeftBracketingBar]" U 1 ❘ "\[RightBracketingBar]" ⁢ sin ⁢ ϕ - ❘ "\[LeftBracketingBar]" I 1 ❘ "\[RightBracketingBar]" · ω ⁢ L ) 2 + ( ❘ "\[LeftBracketingBar]" U 1 ❘ "\[RightBracketingBar]" ⁢ cos ⁢ ϕ - ❘ "\[LeftBracketingBar]" I 1 ❘ "\[RightBracketingBar]" · R ) 2 , wherein |C| denotes the back electromotive force constant of the stepping motor, ωdenotes an angular frequency of the first working voltage, |U1| denotes an amplitude of the first working voltage, ϕ denotes a phase of the first working voltage, |11|denotes an amplitude of the first working current, L denotes the phase inductance of the stepping motor, and R denotes the sum of the phase resistance of the stepping motor and the on-resistance of the H-bridge. ### Claim 13 (depends on 10) The method of claim 10, further comprising: determining the phase resistance of the stepping motor based on an operating environment of the stepping motor. ### Claim 14 (depends on 13) The method of claim 13, wherein the phase resistance of the stepping motor is determined according to R1=R25° C.×(1+(T−25)*0.004), wherein R1 denotes the phase resistance of the stepping motor, R25° C. denotes a phase resistance of the stepping motor when the stepping motor is operated at 25° C., and T denotes a temperature of the operating environment. ### Claim 15 (depends on 10) The method of claim 10, further comprising: driving the stepping motor with a second working voltage; obtaining a second working current of the stepping motor under the second working voltage; and determining the load angle of the stepping motor based on the second working voltage and the second working current. ### Claim 16 (depends on 10) The method of claim 10, further comprising: storing a table indicating a relationship between the driving voltage and the angular frequency. ### Claim 17 (depends on 10) The method of claim 10, wherein the driving the stepping motor to work based on the driving voltage via the H-bridge includes: obtaining pulse width modulation (PMW) signals by inputting an amplitude of the driving voltage to a sinusoidal pulse width modulation (SPWM) generation module; and controlling the H-bridge to drive the stepping motor by inputting the PWM signals to the H-bridge. ### Claim 18 A non-transitory readable medium, comprising at least one set of instructions for controlling a stepping motor, wherein when executed by at least one processor of an electrical device, the at least one set of instructions directs the at least one processor to perform operations including: determining a driving voltage based on a function, wherein the function includes a predetermined electric current and operating parameters of the stepping motor and the function includes |U|=√{square root over ((|I|ωL+ω|C|sin γ)2+(|I|R+ω|C|cos γ)2)}, wherein |U| denotes an amplitude of the driving voltage, |I| denotes an amplitude of the predetermined electric current, the predetermined electric current is a sinusoidal current, ωdenotes an angular frequency of the driving voltage, |C| denotes a back electromotive force constant of the stepping motor, L denotes a phase inductance of the stepping motor, γ denotes a load angle of the stepping motor, and R denotes a sum of a phase resistance of the stepping motor and an on-resistance of the H-bridge; and driving the stepping motor to work based on the driving voltage via an H-bridge.