An electronic watch includes hands, a stepping motor, a drive circuit, a controller, a current detection circuit that detects a current value flowing through the drive circuit, and a storage unit that stores polarity information of a drive pulse output from the controller to the drive circuit, wherein the controller initializes the polarity information stored in the storage unit when the storage unit is initialized, outputs a polarity detection pulse, which does not cause the stepping motor to rotate by one step, to the drive circuit based on the initialized polarity information, performs a polarity determination processing of determining whether a polarity of the stepping motor and the polarity information match based on the current value detected by the current detection circuit in response to the output of the polarity detection pulse, and changes the polarity information when the polarity of the stepping motor and the polarity information do not match.

An electronic watch includes hands, a stepping motor, a drive circuit, a controller, a current detection circuit that detects a current value flowing through the drive circuit, and a storage unit that stores polarity information of a drive pulse output from the controller to the drive circuit, wherein the controller initializes the polarity information stored in the storage unit when the storage unit is initialized, outputs a polarity detection pulse, which does not cause the stepping motor to rotate by one step, to the drive circuit based on the initialized polarity information, performs a polarity determination processing of determining whether a polarity of the stepping motor and the polarity information match based on the current value detected by the current detection circuit in response to the output of the polarity detection pulse, and changes the polarity information when the polarity of the stepping motor and the polarity information do not match.

A control device 10 for a rotary apparatus 1 includes a driving circuit 40 configured to apply a driving voltage to a stepping motor 20 that rotates an output gear 74, and a control circuit 30 configured to output, to the driving circuit 40, driving pulses in a number corresponding to a driving target included in a driving command signal from the outside. The control circuit 30 includes a driving-pulse output unit 61 configured to output the driving pulse in the number corresponding to the driving target, a position-information acquiring unit 52 configured to acquire position information from a potentiometer 75 that reads a rotating position of the output gear 74 of the rotary apparatus 1, and a rotation-abnormality determining unit 59 configured to determine, based on the position information acquired by the position-information acquiring unit 52, whether a rotation abnormality has occurred in the rotary apparatus 1.

A control device 10 for a rotary apparatus 1 includes a driving circuit 40 configured to apply a driving voltage to a stepping motor 20 that rotates an output gear 74, and a control circuit 30 configured to output, to the driving circuit 40, driving pulses in a number corresponding to a driving target included in a driving command signal from the outside. The control circuit 30 includes a driving-pulse output unit 61 configured to output the driving pulse in the number corresponding to the driving target, a position-information acquiring unit 52 configured to acquire position information from a potentiometer 75 that reads a rotating position of the output gear 74 of the rotary apparatus 1, and a rotation-abnormality determining unit 59 configured to determine, based on the position information acquired by the position-information acquiring unit 52, whether a rotation abnormality has occurred in the rotary apparatus 1.

A motor drive control device includes a control unit generating a control signal Sd such that one-phase excitation of exciting, of coils and of two phases of a two-phase stepping motor, a coil for one phase and two-phase excitation of exciting the coils for two phases are alternately repeated, and a drive unit driving the coils of two phases based on the control signal Sd. An energization angle θ representing a magnitude of an electric angle for continuously energizing the coil of one phase in one direction is capable of being set in the control unit. Specifically, the control unit determines a period T1n for performing the one-phase excitation based on a back electromotive voltage generated in the coil non-excited in the one-phase excitation, and determines a period T2n for performing the two-phase excitation based on an elapsed time per unit angle while the two-phase stepping motor is being excited and the energization angle θ.

A motor drive control device includes a control unit generating a control signal Sd such that one-phase excitation of exciting, of coils and of two phases of a two-phase stepping motor, a coil for one phase and two-phase excitation of exciting the coils for two phases are alternately repeated, and a drive unit driving the coils of two phases based on the control signal Sd. An energization angle θ representing a magnitude of an electric angle for continuously energizing the coil of one phase in one direction is capable of being set in the control unit. Specifically, the control unit determines a period T1n for performing the one-phase excitation based on a back electromotive voltage generated in the coil non-excited in the one-phase excitation, and determines a period T2n for performing the two-phase excitation based on an elapsed time per unit angle while the two-phase stepping motor is being excited and the energization angle θ.

A motor drive control device includes a control unit monitoring a rotational state of a rotor of a two-phase stepping motor, setting an energization angle θ representing a magnitude of an electric angle for continuously energizing, of coils of two phases of the two-phase stepping motor, a coil of one phase in one direction based on the rotational state of the rotor, and generating a control signal Sd for controlling driving of the two-phase stepping motor based on the set energization angle θ, and a drive unit driving the coils of two phases based on the control signal Sd.

A motor drive control device includes a control unit monitoring a rotational state of a rotor of a two-phase stepping motor, setting an energization angle θ representing a magnitude of an electric angle for continuously energizing, of coils of two phases of the two-phase stepping motor, a coil of one phase in one direction based on the rotational state of the rotor, and generating a control signal Sd for controlling driving of the two-phase stepping motor based on the set energization angle θ, and a drive unit driving the coils of two phases based on the control signal Sd.

A system and method for reducing power consumption and increasing reliability in a solar tracking system is disclosed. The solar tracker comprises a panel, at least one actuator configured to control the orientation of the panel, and a tracking controller. The tracking controller is configured to determine a minimum operating current for the at least one actuator based on a range of motion of the panel, and energize the at least one actuator based on the minimum operating current. The tracking controller determines the minimum operating current based on the range of motion of the panel, specifically the minimum current need to drive the panel through a measured range of motion equal to or substantial similar to the full mechanical range of motion of the panel. Based on the minimum operating current, solar tracker may generate messages to repair or replace an actuator or gearbox, for example.

A system and method for reducing power consumption and increasing reliability in a solar tracking system is disclosed. The solar tracker comprises a panel, at least one actuator configured to control the orientation of the panel, and a tracking controller. The tracking controller is configured to determine a minimum operating current for the at least one actuator based on a range of motion of the panel, and energize the at least one actuator based on the minimum operating current. The tracking controller determines the minimum operating current based on the range of motion of the panel, specifically the minimum current need to drive the panel through a measured range of motion equal to or substantial similar to the full mechanical range of motion of the panel. Based on the minimum operating current, solar tracker may generate messages to repair or replace an actuator or gearbox, for example.