Abstract: A photographic illumination system, comprising a first stroboscopic flash tube, for emitting an intense broadband illumination pulse comprising ultraviolet rays; a second stroboscopic flash tube, for emitting a continuous series of broadband illumination pulses comprising ultraviolet rays; an optional filter, within a common optical path of the first and second stroboscopic flash tubes, for filtering a portion of the broadband illumination; and a control, for synchronizing the illumination pulse of the first stroboscopic flash tube with an external trigger pulse, wherein the second stroboscopic flash tube provides an output suitable for use by a human, unaided by viewing accessories, to compose a subject at a distance from the first and second stroboscopic flash tubes, and the first stroboscopic flash tube provides an output pulse suitable for exposure of an image capture medium.

Abstract: According to embodiments of the present invention, an LED assembly includes a case that encapsulates a post, an anvil and an integrated circuit. The integrated circuit includes positive and negative power supply inputs. The positive power supply input is electrically connected to the post, whereas the negative power supply input is electrically connected to the anvil. The integrated circuit also includes an oscillator input, and an oscillator output. According to these embodiments, an anode lead connected to the post; and a cathode lead is connected to the anvil. Furthermore, an oscillator input lead is connected to the oscillator input and an oscillator output lead is connected to the oscillator output.

Abstract: A light source manufacturing method includes disposing LEDs upon a substrate having input pads for receiving an operating voltage for the LEDs, bonding a flexible PC board to the substrate, and using a thermally conductive adhesive bonding the substrate onto a planar region of a heat sink.

Abstract: The present invention is aimed at providing a dimmer capable of preventing malfunctions due to noise contamination or waveform distortion of the voltage of an AC power source.

Abstract: Control apparatus for controlling an aspect of an apparatus are disclosed. In certain embodiments, the control apparatus comprises a dimmer that includes a variable impedance. In certain embodiments of the invention, the dimmer may be a TRIAC dimmer having a voltage at a gate electrode of the TRIAC that is always below a trigger voltage for the TRIAC such that the TRIAC never turns on and the remaining components within the TRIAC dimmer can be used as discreet components in a larger circuit. In the control apparatus, the dimmer may be coupled to a signal generation circuit that may generate an output signal whose frequency (period) is dictated at least in part by an impedance of the variable impedance. The output signal may be used to control an aspect of an apparatus such as the intensity, color or color temperature for a lighting apparatus.

Abstract: A light emitting element drive apparatus capable of outputting the lowest voltage satisfying drive conditions and having high light emitting efficiency and low power loss, and a portable apparatus using the same, comprising an LED drive apparatus to which LEDs of different drive voltages required for emitting light are connected in parallel and driving one or more LEDs, wherein the LED drive apparatus has drive circuits connected to the corresponding LEDs among a plurality of LEDs and driving the corresponding LEDs with luminances based on set values and power supply circuits for deciding a drive voltage value required for the highest light emission among one or more LEDs driven to emit light based on drive states of drive circuits (for example terminal voltages of the current source) and supplying a drive voltage having at least the decided value to LEDs in parallel.

Abstract: A device and method to interface with a Magnetic or Electronic Fluorescent Ballast; evaluate, process, and regulate the incoming power from the Ballast device and output a steady AC power that can be used by LED drivers, LED chips, or set of multiple LED chips in a Tube or Bulb application. This device and method will allow for a non-fluorescent replacement lighting device such as a LED Lighting Tube or Bulb to be used in a Fluorescent Light Luminaire (fixture) without any electrical wiring modification or removal of the Electronic or Magnetic Ballast.

Abstract: The present invention relates to a power factor correction circuit and a driving method thereof. The power factor correction circuit refers to an inductor receiving an input voltage and supplying output power, a power switch connected to the inductor and controlling an inductor current flowing in the inductor, and an auxiliary coil coupled with the inductor with a predetermined turn ratio. The power factor correction circuit controls the output power by controlling a switching operation of the power switch, and counts the number of times that the inductor current reaches a predetermined maximum current to turn off the power switch when the count result reaches a predetermined short circuit threshold count.

Abstract: A power converting controller and an LED driving circuit are provided. The power converting controller controls a converting circuit, which converts an input power source into an appropriate power source to drive a load. The power converting controller includes a feedback control unit, an open-circuit judging unit and a protection unit. The feedback control unit controls the converting circuit according to a feedback signal representing the status of the load. As the open-circuit judging unit has judged that the load is continuously in an open-circuit status for a predetermined time length, the open-circuit judging unit generates an open-circuit protection signal. The protection unit is coupled to the feedback control unit and the open-circuit judging unit so as to generate a protection signal as receiving the open-circuit protection signal and thereby the feedback control unit enters a latch status to stop controlling the converting circuit.

Abstract: A ballast circuit is disclosed for inductively providing power to a load. The ballast circuit includes an oscillator, a driver, a switching circuit, a resonant tank circuit and a current sensing circuit. The current sensing circuit provides a current feedback signal to the oscillator that is representative of the current in the resonant tank circuit. The current feedback signal drives the frequency of the ballast circuit causing the ballast circuit to seek resonance. The ballast circuit preferably includes a current limit circuit that is inductively coupled to the resonant tank circuit. The current limit circuit disables the ballast circuit when the current in the ballast circuit exceeds a predetermined threshold or falls outside a predetermined range.

Abstract: A method for determining a limit of a phase control power range includes applying a first gate pulse to a switch at a first firing angle near the limit of the power range, sensing the conductive state of the switch after the first gate pulse, and determining the limit of the power range in response to the conductive state of the switch. If the switch remains conductive after the first gate pulse, the first firing angle may be used as the limit of the power range. If the switch does not remain conductive after the first gate pulse, the limit may be determined by repeatedly incrementing the firing angle, applying a gate pulse to the switch at the incremented firing angle, and sensing the conductive state of the switch after each gate pulse until the switch is conductive after a gate pulse.

Abstract: An electric vehicle accomplishes speed changes through the use of electronically controlled, multiple electric motor configurations that are coupled to an output drive shaft instead of a speed change transmission. A parallel-coupled motor configuration includes at least two motors that are each coupled to the output drive shaft through respective gear arrangements, each gear arrangement having a respective gear ratio. In a serially-coupled motor configuration, the stator of the second motor is coupled to the rotor of the first motor, where the rotor of the second motor is coupled to the output drive shaft. The required torque to reach or maintain a desired vehicle speed can be obtained by selective energization of either one or both of the motors (in both multi-motor configurations). Two motors are also coupled to a differential gear so that the rotational speed contributed by both motors are additive at the output shaft.

Abstract: An inverter device includes a filter circuit, an inverter circuit, an electric current detecting circuit, a voltage detecting circuit, a control circuit for outputting a drive signal so as to switch switching devices, and an internal power supply. The control circuit includes a shutdown circuit for stopping outputting the drive signal to the switching devices when an electric current flowing through a motor is an overcurrent or a voltage across the inverter circuit is an overvoltage or the voltage outputted from the internal power supply is not stabilized. When electric power by residual charge in the capacitor is used after the inverter device is disconnected from a high-voltage battery, the control circuit generates the drive signal based on a reference waveform and three commands for keeping switching devices corresponding to one phase in either ON or OFF state and for switching ON and OFF the other remaining switching devices.

Abstract: A motor control apparatus that controls a DC motor includes a detection unit configured to detect angular speed of the DC motor, a driven member configured to be driven by the DC motor, and a control unit configured to increase, when starting to drive the DC motor, a control value for controlling driving of the DC motor from a first control value to a second control value at a predetermined increase rate, wherein the control unit detects a start-up characteristic of the DC motor based on a detection result of the detection unit, and corrects the first control value or the increase rate according to a result of comparing a detected start-up characteristic and a predetermined start-up characteristic such that the start-up characteristic of the DC motor becomes closer to the predetermined start-up characteristic.

Abstract: A control device is for a motor, especially a brushless DC motor. The control device contains a bridge circuit for generating a rotating field for the motor and a sensor system for detecting a position of a rotor of the motor, a control signal for the bridge circuit being derivable from the signal representing the rotor position. The sensor system includes an absolute value transmitter which detects the absolute position of the rotor and which is configured to derive at least one incremental signal from the absolute position and to make it directly available to a control component for controlling the bridge circuit for commuting the motor.

Abstract: A method for controlling a permanent magnet synchronous motor is disclosed. The method comprises receiving a feedback current from a motor; generating a digital current signal based on the feedback current, the digital current signal indicative of a value of the feedback current; generating a power signal and a first imaginary power signal based on the digital current signal and a three-phase voltage signal; receiving a speed signal indicative of an expected speed of the motor; generating a phase signal based on the speed signal and the power signal; generating a voltage signal based on the speed signal, the power signal, and the first imaginary power signal; and adjusting the three-phase voltage signal for driving the motor based on the voltage signal and the phase signal.

Abstract: A system and process includes continuously determining an applied armature voltage supplied to a polyphase synchronous machine for which a maximum mechanical load is characterized by a pull-out torque. The armature voltage is supplied from a power source via one of many taps of a regulating transformer. The armature voltage being supplied from the power source to the machine is changed by selecting one of the voltage levels from the taps of the regulating transformer. The tap voltage levels are selected based on the determined applied armature voltage to minimize power consumption of the machine while ensuring based on a predetermined confidence level that the pull-out torque of the machine will not be exceeded.

Abstract: The invention relates to an electric device (1) comprising an alternating current electric motor (3) and a control inverter (5) for controlling the phase or phases of the motor (3). The motor (3) comprises, on at least one winding of at least one phase (PA, PB, PC), a point (Ma, Mb, Mc) for measuring a voltage relative to a predefined potential (M), the measurement point (Ma, Mb, Mc) being chosen so that it divides the winding into a first (Za1; Zb1; Zc1) and a second (Za2; Zb2; Zc2) portion such that the electromotive forces (ea1, ea2) induced in the two portions are phase-shifted relative to one another and means (11A; 11B; 11C) for measuring the voltage between the measurement point and the predefined potential. The invention also relates to an associated method for measuring electromotive forces.

Abstract: A method and system are disclosed for heating of robots in cold environments, whereby the robot possesses permanent magnet brushless or three-phase synchronous motors with three motor phases including three stator coils (L1, L2, L3) connected to an inverter controllable by a control-unit and with a rotor with permanent magnet excitation. A current can be applied to at least one phase of the stator coil (L1, L2, L3) of the motor such that, if the motor stands still, a directed magnetic flux (?) is created which interacts with the permanent magnets of the rotor in such a way that the resulting torque will be close to zero.

Abstract: The invention relates to an electrical machine and to a method for the operation thereof, particularly as a drive motor for an electrical tool or as starter generator for a motor vehicle. The electrical machine includes a rotor excited by a permanent magnet and a stator carrying a multi-phase winding, and operates in a voltage-controlled, lower rotational speed range via a transformer on a DC voltage source. The electrical machine can also be operated in a higher rotational speed range by field weakening, and the structure of the machine can be changed by reducing the flux linkage between the rotor and the stator in order to weaken the field. Preferably, the change to the structure of the machine is carried out by turning off winding parts or by switching them between series and parallel connections.

Abstract: A method for collecting operational parameters of a motor may include controlling the energization of a phase winding of the motor to establish an operating point, monitoring operational parameters of the motor that characterize a relationship between the energization control applied to the motor's phase winding and the motor's response to this control, and collecting information of the operational parameters for the operating point that characterizes the relationship between the applied energization control and the motor's response. The collected information characterizing the relationship between the applied energization control and the motor's response may be employed by a neural network to estimate the regions of operation of the motor. And a system for controlling the operation of motor may employ this information, the neural network, or both to regulate the energization of a motor's phase winding during a phase cycle.

Abstract: A tendon tensioning system includes a tendon having a proximal end and a distal end, an actuator, and a motor controller. The actuator may include a drive screw and a motor, and may be coupled with the proximal end of the tendon and configured to apply a tension through the tendon in response to an electrical current. The motor controller may be electrically coupled with the actuator, and configured to provide an electrical current having a first amplitude to the actuator until a stall tension is achieved through the tendon; provide a pulse current to the actuator following the achievement of the stall tension, where the amplitude of the pulse current is greater than the first amplitude, and return the motor to a steady state holding current following the conclusion of the pulse current.

Abstract: The invention provides a motor with a low speed start function and a soft start function. The motor includes a first pulse generation circuit generating a first pulse signal of which a first duty ratio of one of logic levels is increased as a drive voltage corresponding the target rotation speed of the motor is increased, a second pulse generation circuit generating a second pulse signal of which a second duty ratio of one of logic levels is different from the first duty ratio, and a drive control circuit supplying a drive current to a motor coil at the second duty ratio in order to start the rotation of the motor that is stopping and supplying a drive current to the motor coil at the first duty ratio after a predetermined time passes from the start of the rotation of the motor in response to a rotation signal corresponding to the rotation of the motor.

Abstract: Methods, systems, and apparatus include, in one aspect, a method including receiving from a controller a signal for controlling a device for rotating a machine-readable medium; and increasing a bandwidth of a transfer function corresponding to the controller by at least filtering the signal to compensate for a pole of the transfer function.

Abstract: In an apparatus for controlling a sensorless electric motor that drives an electric oil pump, in a case where a rotational speed of the motor deviates from a first range defined between a first upper limit value and a first lower limit value, a rotational speed limiting section generates a current command signal acting for controlling the rotational speed of the motor to suppress deviation of the rotational speed of the motor from the first range, and in a case where deviation of the rotational speed of the motor from the first range is continued for a predetermined time or more, the rotational speed limiting section sets a second range defined between a second upper limit value and a second lower limit value which are respectively displaced from the first upper limit value and the first lower limit value in a direction in which the deviation is continued.

Abstract: Embodiments of the invention are directed to a system for recharging a mobile robot as a power source. In one embodiment the system comprises a power transmission link having a first end positioned at a selectively located charging station and a second end connected to the battery carried by the robot, the transmission link being configured to transmit power from its first end to its second end to charge the battery. The system further comprises a first wireless power transmitter coupled to receive power from a specified power source, and a first wireless power receiver, connected to the first end of the transmission link and located at a prespecified distance from the first wireless power transmitter. The first wireless power receiver is configured to receive power transmitted across the prespecified distance from the first wireless power transmitter, and to provide power to the first end of the transmission link, for transmission to charge the battery.

Abstract: A switch of a connecting circuit is connected between a signal line branched from an input terminal for a pilot signal in a charging inlet and a ground line connected to a vehicle earth, and is turned on/off in response to a control signal from a CPU. The CPU causes the switch to be turned on when a connector is not connected to the charging inlet, and detects a break in a control pilot line based on whether or not a change in the potential of the pilot signal occurs at that time.

Abstract: A portable electronic device has a connector with a first pin and a second pin, and a battery charging circuit having an input coupled to receive current through the second pin to charge a battery of the device. The portable device also has a controller to determine whether the connector is coupled to an external power source (EPS) having a power converter circuit that can provide the current. The controller on that basis drives the first pin to stimulate the power converter circuit to raise voltage on the second pin. Other embodiments are also described and claimed.

Abstract: A wireless power distribution and control system may be used to supply power wirelessly to various devices. The devices in the system may have control over the system and/or over certain features of other devices. For example, a smartphone charging in the wireless power distribution and control system may have access to and control over other devices in the system, such as the overhead lights, or a projector in a conference room. The identification of other devices, as well as commands for controlling these devices may be communicated over the wireless power link. The type and degree of control of each device in that system may vary based on access control levels for the power supplies and connected devices. The devices that receive power may be configured to automatically connect with the power distribution system and to monitor the other devices connected to the system.

Abstract: A vehicle has a low voltage power generating unit mounted thereon, which passively generates low voltage power when the vehicle is electrically connected to commercial power supply through coupling of a connector unit. A winding transformer transforms the commercial power supply input to the primary side with a prescribed ratio of transformation, and the transformation is performed without requiring any control signal from the outside. The AC power with voltage lowered, output from the secondary side of winding transformer, is rectified by a diode unit, and a low voltage power is generated. The low voltage power generated by the diode unit is supplied through a supplementary low voltage DC line to a sub battery and to a controller.

Abstract: A transportable electrical energy storage system includes an electrical energy storage unit, an electrical energy storage unit management system operably associated with the electrical energy storage unit, an AC/DC rectifier operably associated with the electrical energy storage unit management system, and a DC/DC converter operably associated with the electrical energy storage unit management system. The system further includes at least one bi-directional adapter operatively associated with the electrical energy storage unit and a case for protecting the electrical energy storage unit, the electrical energy storage unit management system, the AC/DC rectifier, the DC/DC converter, and the at least one bi-directional adapter.

Abstract: A charging control method for a battery pack including a plurality of battery cells in which a full charge voltage value is initially set as a first voltage value. The charging control method includes: charging the plurality of battery cells to the first voltage value in an initial charge mode; and resetting the full charge voltage value to a second voltage value less than the first voltage value in a subsequent charge mode.

Abstract: Provided are a battery state monitoring circuit and a battery device that are capable of reliably controlling charge by a charger even if a voltage of a secondary battery drops to around 0 V. The battery state monitoring circuit includes a minimum operating voltage monitoring circuit for detecting that the voltage of the secondary battery is lower than a minimum operating voltage of the battery state monitoring circuit. When the voltage of the secondary battery is lower than the minimum operating voltage of the battery state monitoring circuit, an output of an overdischarge detection circuit is set to an overdischarge detected state.

Abstract: A controller identifies a condition of a hazardous internal short by comparing patterns of series element voltages to the last known balance condition of the series elements. If the loaded or resting voltage of one or more contiguous series elements uniformly drop from the previously known condition by an amount consistent with an over-current condition, an over-current internal short circuit fault is registered. The desired response is to prevent the affected series elements from heating to a hazardous temperature by summoning the maximum heat rejection capability of the system until the short ceases and the affected elements cool, the cooling function is no longer able to operate due to low voltage, or the affected series string has drained all of its energy through the short. Also includes are responses that allow the battery pack to continue to power the cooling system even though it may enter an over-discharged state.

Abstract: In a power generator, three-phase armature windings and a switching unit are provided for each phase armature winding. The switching unit includes a pair of a high-side switching element with a first diode and a second low-side switching element with a second diode. The switching unit rectifies, through at least one of the high-side switching element, the first diode, the second low-side switching element, and the second diode, a voltage induced in each phase armature winding. A zero-cross detector detects a point of time when a phase current based on the voltage induced in each phase armature winding is reversed in direction as a zero-cross point of the phase current. A determiner determines an off timing of the high-side switching element or the low-side switching element for each phase armature winding relative to the zero-cross point detected by the zero-cross detector.

Abstract: A rotary electrical machine regulation device of the type which can control the electrical machine using a predetermined set value of a direct voltage (B+) of the on-board electrical network of the vehicle in which the machine is installed. An excitation current (EXC) is supplied to the alternator (machine), and has a duty cycle (RC) which is determined by a digital processing block (9), on the basis of an error voltage between the predetermined set value and the direct voltage of the electrical network. Accordingly, a system (11) is provided herein for making the digital block electrically self-sufficient. The system includes a voltage maintenance device with a self-sufficient capacitor (110), and a self-sufficient control element (111).

Abstract: A switching circuit (Q11, Q12, D11, D12, D13, L11, L12) is repetitively configured to charge an energy transfer capacitance (C11) from an electrical supply (V11) and then inject a discrete pulse of energy into a resonated load circuit by discharging the capacitance. The load circuit is formed by a resonating capacitance (C12) and an inductive load device (T11, R11), eg motor, or induction heating or power transfer device. Energy circulates in the load circuit at or near to its natural resonant frequency. There is no injection of energy into the load circuit while energy for charging the transfer capacitance is being delivered from the supply to the switching circuit. During injection, the two capacitances and the inductive load device may be connected together in parallel or in series, or the transfer capacitance may be connected in series with the inductive load device but not the resonating capacitor.

Abstract: This document discusses, among other things, a regulator circuit. The regulator circuit can controllably connect a first voltage to an inductor using a first switch and can controllably connect a second voltage to the inductor using a second switch. The first switch can be turned off and the second switch can be turned on for a duration proportional to a difference between the first voltage and a third voltage, divided by the first voltage. The first switch can be turned off and the second switch can be turned on for a duration proportional to the third voltage divided by the first voltage. One of the first or third voltages can correspond to a desired output voltage.

Abstract: A multimode voltage regulator comprises an output for providing a regulator output voltage Vdd and an output current to a load and a low power reference voltage source having a reference voltage output providing the regulator output voltage Vdd, when in a first low power mode the output current is not greater than a threshold value. It may comprise a buffer amplifier having an output providing the regulator output voltage Vdd, when the output current is greater than the threshold value and a first bias voltage input being connected in a second low power mode to the reference voltage output when the output current is greater than the threshold value for less than a predefined time. And it may comprise a mode controller for automatically determining the output current and automatically switching from first low power mode to second low power mode.

Abstract: An output voltage controller includes a first controller which controls current supply to a inductor based on an output voltage, and a second controller which controls current supply to the inductor by controlling a period when an input end to which an input voltage is inputted, the inductor, and an output end from which the output voltage is outputted are coupled based on the input voltage.

Abstract: The embodiments of the present invention illustrate a means for digitally controlling a converter system and associated method. Wherein the means for digitally controlling a converter system comprises a means for generating a digital error signal according to an output voltage of the converter system and a reference voltage, a means for generating a digital control signal according to a digital reference signal and the digital error signal, and a means for generating a PWM signal according to the digital control signal in order to control the converter system. The means for digitally controlling a converter system and associated method at least alleviate the problem of limit-cycle oscillation, and promote the performance of system transient response and accuracy.

Abstract: A DC-DC converter for generating an output voltage from input voltage, includes: an output stage for outputting the output voltage; an error amplifier having an input and a reference input for receiving a feedback voltage at the input in accordance with the output voltage and for receiving a reference voltage at the reference input, the error amplifier generating an amplified voltage for driving the output stage, the amplifier voltage corresponding to the difference between the feedback voltage and the reference voltage; a phase compensation unit for generating a phase compensation component to the feedback voltage; and a phase compensation controller for controlling the phase of the phase compensation unit; wherein the feedback voltage is determined by the output voltage plus said phase compensation component.

Abstract: A regulator control circuit includes a high side driver that is configured to receive a supply voltage. A capacitor is configured to store charges. A first transistor is coupled between the capacitor at a first node and a gate of a high side driver at a second node. The first node is capable of being boosted to a voltage to operate the first transistor at a saturation mode for a charge sharing between the first node and the second node so as to substantially turn on the high side driver.

Abstract: In one embodiment, an apparatus includes a transistor having a gate, a drain, and a source. The drain is coupled to receive an AC power supply signal. A component is coupled between an output node and the gate of the transistor. The component couples an output voltage from the output node to charge a gate-source capacitor during a first portion of the AC power supply signal. The transistor is configured to turn on during a second portion of the AC power supply signal to send a charge to the output node where the charge is used to power a circuit of a power supply.

Abstract: Integrated circuits with voltage regulation circuitry are provided. Voltage regulation circuitry may be powered by a core supply voltage and may not have a bandgap reference circuit. Voltage regulation circuitry may have an error amplifier in a negative feedback configuration. The error amplifier may have inputs connected to reference voltages generated by resistor strings. The resistor strings may be trimmable to provide a desired negative voltage. The desired negative voltage may be fed to the gates of transistors to help reduce leakage. The desired negative voltage may be have improved tolerance to process-voltage-temperature variations and may improve the reliability of transistors.

Abstract: A system for use within an integrated circuit (IC) can include an input differential pair including a positive input node and a negative input node, a current source coupled to the input differential pair, and a current mirror. The current mirror can include at least a first active device and a second active device. The system can include a biasing transistor device having a source terminal coupled to a gate terminal of each of the first and second active devices, a gate terminal coupled to a drain terminal of the second active device, and a drain terminal coupled to a voltage source. The biasing transistor device is complementary to the current mirror.

Abstract: In some embodiments, a multi-phase converter with dynamic phase adjustment is provided. In some embodiments, a controller may include circuitry to control how many phase legs are active based on output current and also which phase legs are to be enabled.

Abstract: In a method for current measurement in a multiphase current network, a conductive connection is produced between a plurality of the phases of the multiphase current network such that the plurality of the phases is short-circuited with one another. At a detection time, a current value flowing between the conductive connection and a first voltage potential is detected.

Abstract: Systems and/or methods are provided for a dual-channel inductive proximity sensor. The sensor can include a sensing element which includes a core having a first cavity and a second cavity, a first coil accommodated within the first cavity of the core, and a second coil housed within the second cavity of the core. Each coil can be independently driven by oscillators to generate respective magnetic fields. The magnetic fields can be monitored to determine whether detection of a target object occurs.

Abstract: A rotation angle detection device includes: a detection portion that detects detection angle that univocally corresponds to rotation angle of a rotating body which is within a predetermined range, wherein the detection angle linearly increases from a minimum value to a maximum value as the rotation angle increases within a unit range, and the detection angle changes from the maximum value to the minimum value or from the minimum value to the maximum value at a boundary between unit ranges that are adjacent to each other; and a correction portion that corrects the detection angle so that the detection angle detected in the predetermined range has linear characteristics, if the boundary between the unit ranges is contained in the predetermined range.