342 results about "Rotor speed" patented technology

The invention relates to a non-inductive FOC open-loop to closed-loop switching method and device for an electronic water pump and a vehicle. The method comprises the steps that a rotor is pre-positioned; starting an open loop I-F; switching condition judgment; estimating the rotor speed based on an observer, calculating a normalization factor, and obtaining a mixed scale factor through cubic polynomial operation; acquiring an open-loop current instruction of a q axis and a closed-loop current instruction output by a closed-loop speed PI regulator; performing weighted synthesis on the two paths of current instructions according to the mixing scale factor to obtain a temporary target current instruction, and applying a change rate limit to obtain a final current instruction output in the current period; the original angle error of the observer estimation angle and the open-loop slope angle is calculated and normalized, the allowable adjustment step length and direction of the round are dynamically determined, and the angle correction amount of the round is generated and superposed to the open-loop slope angle to update the rotor angle reference value; and closed-loop switching is completed. According to the invention, the problems of electromagnetic torque impact and rotating speed fluctuation caused by instruction step change are solved.

This disclosure pertains to the field of wind power technology and provides a method, system, equipment, and medium for calculating the velocity distribution of a wind turbine wake field. The method includes: acquiring wind speed, rotor speed, and airfoil aerodynamic data; constructing a prediction function for the wind turbine based on blade deformation data to output load distribution; inputting current blade deformation data to obtain the load distribution; calculating the blade spanwise circulation distribution based on relevant data; obtaining the intensity of wake vortices and shedding vortices based on the circulation distribution, thereby obtaining the wake control point position vector; and solving for the velocity distribution at any location within the downstream wake field of the wind turbine. This process aims to more accurately predict the relevant characteristics of the wind turbine wake field and solve the problem that existing wake field prediction models cannot consider the true shape of the wake. This method can consider the true shape of the wake to obtain an accurate wake field velocity distribution.

The invention belongs to the field of offshore wind power, and discloses a single-pile offshore wind turbine power regulation and load relief method, which comprises the following steps of: constructing a thrust system model of wind to a rotor and a tower; constructing a dual-mass transmission system model of the wind turbine generator; constructing a tower top front-back displacement model and a pile soil front-back displacement model; constructing a rotor speed tracking error model based on an adjustment error method; constructing a tracking error model of the change rate of the front-back displacement of the tower top; constructing an optimal control strategy based on an infinite vision field optimal cost function; and designing an optimal pitch control scheme based on a robust adaptive dynamic programming algorithm. According to the design of the RADP-based propeller pitch controller provided by the invention, the MOWT model does not need to be completely known, so that the calculation cost of the controller is reduced, and the calculation efficiency is improved.

The invention discloses a method, a system, a medium and equipment for evaluating a blade tip timing vibration displacement measurement error under a variable rotating speed. A blade end vibration displacement measurement value is generated based on an included angle between a blade end timing sensor and a rotating speed sensor, an included angle between a rotor blade root and a key phase reference on a rotating shaft, reference arrival time measured by a key phase sensor and a blade end rotating radius; a blade end timing vibration displacement measurement error mathematical model under the variable rotating speed is established, and a measurement error caused by the variable rotating speed is obtained based on the blade end vibration displacement measurement value; evaluating the maximum error of the blade tip timing vibration displacement measurement under the variable rotating speed, and obtaining the maximum error of the blade tip timing vibration displacement measurement under the variable rotating speed based on the measurement error; based on the measurement error and the blade end timing vibration displacement measurement maximum error under the variable rotation speed, the influence of the rotor rotation speed change speed and the blade initial angle position on the blade end timing vibration displacement measurement error is quantified.

The invention relates to the technical field of aero-engine aerodynamic optimization and computer aided design, and discloses a response surface modeling-based aero-engine low-pressure turbine blade leading edge model numerical optimization design method and structure. According to the method, the wake injection angle is changed by adjusting the flow or the rotating speed of a rotor, accurate matching of Klebanoff stripes and large-scale vortex generation opportunities is achieved, stripe impact is promoted, and large-scale vortex fracture is accelerated; and meanwhile, by constructing a blade front edge modeling parameterization model and establishing a response surface agent model of a modeling design variable parameter combination and a boundary layer velocity mean square error, an optimal design variable parameter combination is determined in a constraint domain by taking maximization of the velocity mean square error in a boundary layer as a target. On the premise that the blade profile load is not changed, the momentum thickness and the total pressure loss of the boundary layer are effectively reduced, the design efficiency and the engineering applicability under the working condition of the low Reynolds number are improved, an additional flow control structure does not need to be introduced, and the structure is simple and easy to implement.

The invention relates to the technical field of unmanned aerial vehicle control, in particular to a physical-data hybrid fault diagnosis method and system for an electric vertical take-off and landing aircraft. The method comprises the following steps: firstly, selecting a proper flight state variable to construct an observer, and generating a residual signal between a rotor rotating speed estimation value and a tracking value; secondly, introducing a random forest to realize positioning isolation of rotor faults; a data set is constructed by integrating physical model data, a random forest classification model is trained, a physical-data hybrid diagnosis model is established, dynamic association between flight states and faults is captured, and multi-fault diagnosis of eVTOL under closed-loop control is realized.

A method for damping drivetrain vibrations of a wind turbine. The drivetrain has, at least, a rotor and a generator. The method includes receiving a first rotational speed signal at a first location along the drivetrain, the first rotational speed signal being a proxy for rotor speed of the rotor. The method also includes receiving a second rotational speed signal at a second location along the drivetrain, the second location being downwind from the first location, the second rotational speed signal being a proxy for generator speed of the generator. Further, the method includes determining a speed error based on a comparison of the first and second rotational speed signals. Moreover, the method includes determining a torque deviation signal for the wind turbine configured to dampen the drivetrain vibrations when the speed error exceeds a first speed threshold. In addition, the method includes applying the torque deviation signal to the generator to dampen the drivetrain vibrations.

The invention aims to provide the clearance distance signal extraction and safety control method based on the laser radar, which is accurate in signal identification, clear in computational logic and efficient in closed loop control. The method comprises the following steps: a, fixing a laser radar system below a cabin of the wind driven generator; b, measuring the distance from the laser radar unit to a target point at the tail end of the blade by adopting a flight time principle; c, a data processing unit of the fan receives measurement data of the multiple laser radar units, an effective blade reflection signal is recognized through a signal aggregation statistical method, and the clearance distance between the blade and the tower is calculated according to the reflection signal; d, the clearance distance data between the blades and the tower is monitored in real time, and the optimal pitch angle adjustment amount is calculated through a fan control system in combination with the wind speed and rotor rotating speed parameters; and e, dynamically adjusting the pitch angle of the blade through a variable pitch execution mechanism of the fan. The method is applied to the technical field of laser radars.

The invention relates to the technical field of motor control, and discloses a vector control application of a direct drive motor, which comprises the following steps: S1, collecting stator current, rotor speed and bus voltage signals of the motor, and carrying out filtering preprocessing on the collected signals; and S2, constructing a self-adaptive flux linkage observation model, estimating a stator flux linkage in real time based on stator current and bus voltage signals in combination with rotor rotating speed information, and correcting stator resistance and inductance parameters through a model reference self-adaptive algorithm. According to the method, the motor parameters are corrected in real time through the self-adaptive flux linkage observation model, parameter drift caused by factors such as temperature change and magnetic saturation is effectively counteracted, and the accuracy of flux linkage estimation is improved; the improved PI regulator realizes online self-tuning of control parameters through a fuzzy control algorithm, can quickly adapt to changes of dynamic characteristics of the motor, and shortens the regulation response time of flux linkage and torque; and the resistance of the system to external interferences such as load fluctuation, power supply voltage change and the like is enhanced.

The magnetizing system comprises a tray, a positioning chuck, a tip cone piece and a magnetizing head, a magnetic induction unit is arranged in the magnetizing head, the rotor is driven by the positioning chuck to rotate, the tip cone piece abuts against the other end of the rotor, the system comprises a parameter initialization module, a magnetizing parameter database is loaded, and initial parameters are preset; the magnetizing simulation calculation module is used for obtaining pre-estimated parameters such as magnetizing time through finite element simulation based on the magnetic induction intensity; the magnetic uniformity detection module is used for monitoring and calculating the magnetizing uniformity in real time; and the parameter dynamic regulation and control module is used for regulating the rotating speed of the rotor according to the uniformity and regulating and controlling the magnetizing current through a temperature sensor and a mapping model. The problems that in the magnetizing process of an existing permanent magnet motor rotor, magnetizing uniformity is insufficient, a real-time monitoring and dynamic adjusting mechanism is lacked, and the magnetizing quality is unstable and positioning precision is poor due to the fact that the magnetizing quality is prone to being affected by temperature are solved.

The invention discloses a brushless motor rotor angle determination method and device, equipment and a storage medium. The method comprises the following steps: synchronously acquiring original angle data of a Hall sensor, an incremental encoder and a back electromotive force observation module; respectively determining confidence coefficients of the Hall sensor, the incremental encoder and the back electromotive force observation module according to the rotating speed of the rotor, and performing weighted fusion on the original angle data of the Hall sensor, the incremental encoder and the back electromotive force observation module to obtain an initial fusion angle; based on the motor temperature, the motor phase current and the rotor speed, calculating a temperature drift compensation angle through a segmented temperature drift coupling model, and compensating the initial fusion angle according to the temperature drift compensation angle to obtain a temperature drift compensated angle; and inputting the temperature drift compensated angle into an extended Kalman filter for state estimation and filtering to obtain a rotor angle estimation value at the current moment. By means of the method, high-precision real-time calculation of the rotor angle within the wide temperature range and the full rotating speed range can be achieved.

A ride-on power trowel has first and second engines mounted to a rigid frame. Each of first and second drive loops have a hydraulic pump powered by such an engine and a drive motor powered by the hydraulic pump. Rotor assemblies are coupled to the drive motors and configured to contact a concrete surface beneath the frame. A feedback controller sets rotor speed in each assembly to a power limited speed based on loads sensed in the drive loops. The power limited speed is an estimated maximum rotor speed achievable for the highest sensed load, which may be affected by operating data received from the engine associated with the highest sensed load.

The invention belongs to the technical field of wind power control, and discloses a wind driven generator fixed time adaptive neural network variable pitch control method, which comprises the following steps: step 1, establishing a kinetic model of a wind driven generator, and initializing a system state and control parameters; 2, aiming at the wind driven generator system with external interference, designing a fixed time sliding mode surface based on a sliding mode thought; and step 3, designing a fixed-time adaptive neural network variable pitch controller. The method has the advantages that under the conditions that external interference exists in the wind driven generator and parameters are uncertain, rapid convergence of the rotor rotating speed tracking error within fixed time is achieved, and the convergence time does not depend on the initial state.

The invention discloses a wind turbine generator multi-stage self-adaptive droop control method considering rotor kinetic energy constraint and frequency change rate, which comprises the following steps: 1, constructing a rotation speed influence factor based on a Logistic function, mapping a rotor rotation speed into a frequency modulation contribution coefficient, and quantitatively evaluating a rotor kinetic energy releasable range of a fan under different operation conditions; 2, designing a self-adaptive droop control strategy based on a segmented frequency change rate, adjusting a droop coefficient in real time by identifying a frequency change rate interval, forming a hierarchical response mechanism, providing strong active support in a sharp frequency drop stage to quickly suppress frequency drop, and converting into moderate support in a frequency recovery stage to maintain stability and prevent secondary drop; and 3, building a wind-fire combined system simulation model, and verifying the effectiveness of the provided strategy in the aspects of improving the frequency response characteristic of the system and improving the frequency stability through a multi-scene contrast experiment. According to the method, the frequency regulation capability of the power system under the high wind power permeability can be remarkably enhanced.

The invention provides a blade state monitoring method, device and system of a wind turbine generator. The blade state monitoring method of the wind turbine generator comprises the following steps: acquiring an impeller rotation video of the wind turbine generator; performing frame-by-frame image processing on the impeller rotation video to obtain a real-time clearance value of each blade in the impeller, and constructing clearance time sequence data of each blade by using the real-time clearance value of each blade; obtaining an unbalanced component sequence of each blade by using the clearance time sequence data of each blade and a preset clearance reference value; and determining the unbalance level of the impeller according to the unbalance component sequence of each blade and the rotating speed time sequence data of the impeller. According to the invention, the online real-time monitoring of the operation state of the wind turbine generator blade can be realized in a non-contact manner, the deployment is flexible, the precision is controllable, and the hardware cost is low.

The application discloses a kind of offshore wind turbine pitch control methods based on predefined time adaptive dynamic programming, comprising: establishing single-pile offshore wind power generator full coupling mathematical model;The single-pile offshore wind power generator full coupling mathematical model includes the motion equation of system and the mathematical model of double-mass transmission system;Using the mathematical model of double-mass transmission system constructs rotor speed tracking error, adopts error adjustment method to process the non-affine characteristic of system, obtains the nonlinear affine model of single-pile offshore wind power generation system in combination with motion equation;The control strategy is constructed as the infinite time domain optimal performance index function of the change of pitch angle;Using predefined time nonlinear disturbance estimator estimates disturbance term in nonlinear affine model;To the equivalent form of Hamilton-Jacobi-Bellman equation of infinite time domain optimal performance index function, the approximate optimal control method based on only evaluation type neural network is used to solve equation to obtain optimal control strategy.

The present application relates to the technical field of aero-engine aerodynamic optimization and computer-aided design, and discloses a numerical optimization design method and structure for aero-engine low-pressure turbine blade leading edge modeling based on response surface modeling. The method realizes precise matching of Klebanoff stripe and large-scale vortex generation timing by adjusting flow or rotor speed to change wake injection angle, and promotes stripe impact and accelerates large-scale vortex breakup. Meanwhile, by constructing a blade leading edge modeling parameterization model and establishing a response surface proxy model for the combination of modeling design variable parameters and boundary layer velocity mean square deviation, the optimal design variable parameter combination is determined in the constraint domain with the maximum velocity mean square deviation in the boundary layer as the target. The present application effectively reduces the boundary layer momentum thickness and total pressure loss under the premise of ensuring constant blade load, improves the design efficiency and engineering applicability under low Reynolds number conditions, and does not need to introduce additional flow control structures, thus being simple in structure and easy to implement.

The hot fluorine defrosting valve for the refrigerating unit comprises a valve body, a main pipe, a first branch pipe and a second branch pipe are arranged on the valve body, a connecting plate is fixedly connected to the top of the valve body, a servo motor is installed on the top of the connecting plate, a rotating shaft of the servo motor penetrates through the top of the valve body, and the rotating shaft of the servo motor is fixedly connected with the main pipe. The first branch pipe is fixedly connected with a valve element, a rotor is installed in the first branch pipe, and a Hall sensor and a temperature sensor are installed on the inner wall of the first branch pipe. According to the utility model, the microcontroller receives a temperature signal monitored by the temperature sensor, and precisely controls the servo motor to adjust the position of the valve core by combining with the rotating speed of the rotor detected by the Hall sensor, so that high-temperature and high-pressure hot fluorine enters the evaporator for defrosting, the Hall sensor ensures the stability of flow, and the temperature sensor monitors the temperature of a pipeline in real time; the microcontroller automatically controls the servo motor to adjust the state of the valve element according to sensor data and preset data.

The invention discloses a jitter suppression method and system for an AGV. The method comprises the steps that a rotor speed signal and a torque instruction signal of a permanent magnet synchronous motor of the AGV are collected; performing discretization sampling on the rotor speed signal to obtain a discrete speed signal; performing spectral analysis on the discrete speed signal to extract a corresponding vibration spectrum, and obtaining a main frequency point where resonance occurs; inputting the discrete speed signal into a high-pass filter to extract a component required by active damping suppression of a vibration frequency point, carrying out discretization differential on the discrete speed signal to obtain an acceleration signal, and carrying out band-pass filtering on the acceleration signal by adopting a band-pass filter to obtain a component required by acceleration feedback suppression; the cut-off frequency of the high-pass filter and the center frequency and bandwidth of the band-pass filter are determined by main frequency points; and a compensation torque signal is obtained according to the jitter component and the component required for acceleration feedback suppression, so that jitter caused by resonance of the AGV is suppressed according to the compensation torque signal.

The application relates to a test method, device, test equipment and storage medium of an inductive loop system. The method comprises the following steps: obtaining a rotor position of a rotating motor as a reference position, a certain length of a transmitting antenna is installed on the rotor; when the transmitting antenna rotates relative to a cross inductive loop, an envelope signal of the cross inductive loop is obtained, a position of a carrier generating unit in the cross inductive loop is obtained as a test position according to the envelope signal, the carrier generating unit comprises the transmitting antenna, the cross inductive loop is laid on the inner wall of a stator of the rotating motor in a splicing mode, the gaps between adjacent cross inductive loops and the rotor are different, a test result of a positioning function of the inductive loop system is obtained by comparing the reference position and the test position, and a test result of a speed measurement function of the inductive loop system is obtained according to waveforms of the envelope signals under different rotor speeds.

The invention relates to the technical field of bearings, and discloses a composite sliding bearing, a double-rotor adjustable-speed motor and a lubricating method, and the bearing integrates a first bearing bush assembly and a second bearing bush assembly which are used for supporting an inner rotor and an outer rotor into the same bearing seat. The first oil inlet path and the second oil inlet path independently lead to the two bearing bush assemblies, and the oil guide structures and the oil rings are arranged on the bearing bush assemblies and used for establishing oil films for lubricating the inner rotor and the outer rotor respectively. And a first oil return cavity and a second oil return cavity for collecting two paths of return oil respectively are arranged in the lower bearing seat, are communicated with each other and are converged into the same return oil outlet. The double-rotor speed regulation motor adopting the bearing is axially compact in structure, independent supporting and integrated lubrication of the double rotors are realized through a single bearing body, an external oil way is simplified, the bearing capacity is improved, and the rotating speed range is widened.

The application discloses a wind power plant control method and device considering rotor speed dynamic constraint, and the method comprises the following steps: obtaining the operation parameters of synchronous units in a power grid; constructing an additional active control model of the wind power plant containing power optimization control; linearizing the power grid frequency and the synchronous unit output power according to the operation parameters and the additional active control model combined with the piecewise function principle to obtain a total power increment piecewise linear expression of the wind power plant; performing piecewise fitting according to the wind power coefficient and the rotor speed to obtain a first equation; obtaining a rotor speed piecewise expression according to the wind power plant rotor motion equation, the first equation and the total power increment piecewise linear expression; adjusting the control parameters of the wind power plant in each speed section according to the rotor speed piecewise expression; the control parameters at least include primary frequency modulation parameters; and controlling the wind power plant according to the control parameters.

The embodiment of the invention discloses a method, equipment and device for determining the dynamic balance quality of a servo motor and a medium. The method comprises the following steps: obtaining a rotor speed signal of the servo motor at a set speed; determining an amplitude of a first-order component of the rotor speed signal; comparing the amplitude with a standard amplitude corresponding to the set speed, the standard amplitude being determined based on a calibration process of a standard servo motor of the same type as the servo motor, and the standard servo motor comprising a standard rotor; and determining the dynamic balance quality of the servo motor based on the comparison result. And a special dynamic balance measuring instrument is not needed to determine the dynamic balance quality, so that the cost and the test time are reduced.

This invention relates to the field of unmanned aerial vehicle (UAV) control technology, specifically to a tilting rotor omnidirectional UAV control method and related equipment. By acquiring the UAV's current pose information (including position, attitude, and body angular velocity) and desired pose information, the position controller generates a desired total force based on the position deviation, the attitude controller generates a desired angular velocity based on the attitude difference, and the angular velocity controller generates a desired total torque based on the angular velocity deviation, forming a three-level control closed loop. The control distributor uses a rotor configuration dynamics model to convert the total force and torque into desired thrust for each rotor, calculates the desired rotational speed based on the thrust-rotor speed correspondence, and controls the rotor rotation. This scheme achieves decoupling optimization of position and attitude control, improving pose control accuracy and response speed.

This invention relates to the field of unmanned aerial vehicle (UAV) flight control technology, and discloses a method for adaptive adjustment control of UAV flight attitude. Addressing the problems of unstable flight and untimely or inaccurate attitude adjustment of UAVs in complex weather conditions and variable terrain, this method deploys multiple types of sensors on the UAV to collect flight data in real time, including information such as air pressure, wind speed and direction, and attitude angles, and transmits the data to a central processing unit (CPU). The CPU analyzes and processes the data based on a preset algorithm model. When it detects a deviation in flight attitude from a set value, it automatically adjusts the UAV's rotor speed, wing angle, and other actuators to achieve rapid adaptive adjustment of flight attitude. This method effectively improves the flight stability and reliability of UAVs in complex environments and can be widely applied in fields such as aerial surveying, material delivery, and environmental monitoring, ensuring efficient and safe operation of UAVs.

The application discloses a wind farm optimal control method based on rotor kinetic energy upward frequency modulation, comprising: real-time monitoring of wind farm grid-connected point frequency, starting upward frequency modulation function when the frequency is lower than the lower limit of frequency modulation dead zone, recording relevant parameters; continuously monitoring wind farm frequency and each wind turbine state, judging whether to exit frequency modulation state; updating total active power given value according to wind farm virtual inertia time constant and primary frequency modulation coefficient; updating operation mode and wind turbine state according to frequency modulation duration, wind turbine speed, mechanical power and active power, determining active power maximum output, realizing speed and mechanical load protection; optimizing distribution of each wind turbine active output, issuing instructions, realizing upward frequency modulation. The application optimizes distribution of wind farm frequency modulation power, realizes flexible rotor speed recovery control of each wind turbine, reduces mechanical power loss of wind turbine during wind farm utilization of rotor kinetic energy upward frequency modulation, reduces frequency secondary drop amplitude, improves performance and economy of wind farm participation in upward frequency modulation.

The invention relates to the technical field of power systems, in particular to a wind power plant frequency modulation capability evaluation method based on multi-dimensional dynamic aggregation and application thereof. The wind speed, the rotor speed, the grid-connected active output and the pitch angle are selected as grouping indexes for clustering, quantitative evaluation of the system frequency response capability and the frequency modulation recovery capability is carried out by taking the wind turbine generator obtained by clustering as a unit, and the frequency modulation capability of the wind turbine generator is comprehensively evaluated according to the quantitative evaluation results of the system frequency response capability and the frequency modulation recovery capability. The objective of the invention is to solve the problem of how to evaluate the dynamic characteristics of the wind power plant.

The invention relates to the technical field of calcium carbonate processing, in particular to a multi-rotor speed-adjustable airflow classification superfine calcium carbonate vertical mill system which is characterized in that a material sensing module is used for collecting real-time particle size distribution of materials, temperature and pressure of a grinding cavity, classification airflow speed and grinding load information; the intelligent regulation and control center is used for evaluating the grinding state, predicting the particle size of the graded materials and intelligently identifying and positioning abnormal events; the multi-rotor speed-adjustable grading assembly dynamically adjusts the rotating speed and airflow guide parameters of multi-stage rotors according to the real-time monitoring data and the prediction result, and the superfine calcium carbonate with different particle sizes is precisely graded; the grinding cavity collaborative optimization unit dynamically adjusts the pressure of a grinding roller and the rotating speed parameter of a grinding disc based on material grinding characteristics and grading requirements, and generates a collaborative regulation and control strategy; and the coarse powder dynamic back-grinding unit dynamically adjusts the back-grinding conveying speed and path according to the particle size distribution and accumulation state of the coarse powder, and the coarse powder is accurately conveyed back to a designated grinding area of the grinding cavity. Therefore, the problems of high energy consumption, low grading precision and the like in the prior art are solved.

An automatic variable flux axial liquid-cooled motor, relating to the field of motor technology, aims to solve the problems of complex and costly weak flux control in existing motors. The motor includes an upper cover and a lower housing with water channels. The stator is installed inside the lower housing, with its core tightly fitted to the water channels for efficient heat dissipation. The rotor is located above the stator and is slidably connected to the output shaft via a spline, allowing axial sliding and stable torque transmission. Four evenly distributed flyweights are arranged on the upper side of the rotor. A return spring is mounted above each flyweight, and a push rod is attached below. The other end of the push rod rests against a shoulder at the spline end of the output shaft (the shoulder serves both positioning and support functions). During operation, as the rotor speed increases, the centrifugal force of the flyweights increases, and the unfolding angle widens, pushing the push rod downwards and causing the rotor to slide upwards. This increases the air gap between the stator and rotor, increasing leakage flux, reducing magnetic flux linkage and back electromotive force, thereby widening the speed range and improving efficiency. When the speed decreases, the return spring resets the flyweights, and the air gap recovers. This structure integrates automatic flux adjustment and axial liquid cooling functions, offering a simple structure and high efficiency.

A method for detecting a deviation of a position sensor is provided, which detects a deviation in the mounting positions of position sensors of a motor. The invention is a method for detecting a deviation of a position sensor, wherein the method includes: switching on an energy supply to a U-phase conductor wire, a V-phase conductor wire and a W-phase conductor wire.-Conductor wire of a motor to rotate a rotor of the motor; switching off the power supply to the U-phase conductor wire, the V-phase conductor wire and the W-phase conductor wire when a rotor speed reaches a predetermined speed; measuring induced voltages generated in the U-phase conductor wire, the V-phase conductor wire and the W-phase conductor wire in the off state, calculating the positions of a U-phase tooth, a V-phase tooth and a W-phase tooth of the motor based on the induced voltages and measuring outputs from a U-phase position sensor, a V-phase position sensor and a W-phase position sensor; and calculating differences between intended and actual mounting positions of the U-phase position sensor, the V-phase position sensor, and the W-phase position sensor by comparing the calculated positions with the outputs. [Selected drawing].