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Ballscrew drive system has high mechanical efficiency and is able to get high gear ratio easily. But it also has non liner friction elements like rolling friction and viscous friction, so it makes ballscrew control accuracy worse. For that reason, it is proposed that inserting disturbance observer into control system and compensating disturbance torque. Generally, rotary encoder is used for position sensor in ballscrew control, but its resolution affects accuracy of drive control and disturbance observer. In this paper, we propose a speed control system using AC servo motor ball screw drive system, compare driving characteristics in low speed range when using low resolution encoder and high resolution encoder as position sensor. Also we examine effects for driving characteristics by using and compensating disturbance observer. These verifications were carried out by simulation and actual machine.

This research is a proposal of a novel transfer device using a Transverse Flux-Flux Reversal Linear Motor (TF-FRLM). Transfer device in this paper is mounted on a carrier apparatus which was operated in parallel synchronous operation. This digest mainly discusses the overview of a novel transfer device and the optimization result of C-core TF-FRLM. The section of new transfer device describes the basic structure and basic operation. In the section on optimization, the results of dimensional change are shown on the graph and the optimum points are discussed. Three-dimensional finite element analysis is used for dimension optimization.

For construction of high precision positioning system with robustness for disturbance, it needs more precision motor drive control. It is requested robust and reliable position sensor when driving the motor in bad condition that have many vibration, so the resolver and R/D converter are mostly used. But for precision motor drive, it needs accuracy of position sensor, which is affected by R/D converter specification when using resolver especially at low speed range. In this paper, we target that realizing precision positioning servo system without affected disturbance, and propose the mechanism integrating PMSM rotor with ballscrew shaft using resolver as position sensor. We examine improving position detection accuracy at low speed range by changing conversion method and excitation method of R/D converter.

Steer-by-wire system (SBW), which is a new steering system, is expected to be adapt automated driving vehicles. However, SBW has problems with increasing cost and redundancy and these hinder its popularization. Recently, a lot of research about SBW has proposed a system using disturbance torque observer to obtain steering torque or reaction torque with low costs. A resolution of a position sensor directly affects the disturbance estimation accuracy at this time, so a high resolution position sensor is required for the system. But it is inappropriate for SBW to adopt it because of increasing costs. In this paper, therefore, we aim to improve the estimation accuracy of disturbance torque observer with keeping low cost. For that purpose, we propose new method which can improve the position information accuracy by using instantaneous speed observer, and we compare the result between new method and conventional one.

The mechanical simulation analysis of a 2-DOF parallel robot with Considering the dynamic disturbance torque was investigated. We devised a method to derive the position of the end effector using forward kinematics. We also requested inverse kinematics. Next, the operation region was calculated using this method. Using the model of the inertial system, we confirmed the difference in motion in the influence of the inertia term. We investigated the possibility of reducing the influence of the inertia term by using the moment of inertia at an appropriate value.

The 10poles-l2slots brushless DC motor is superior as AC servo motor by sine-wave excitation, but its characteristics like efficiency get worse by using as BLDC motor by square-wave excitation. However, 150degree excitation which adjusted excitation angle and excitation phase can increase 3% of efficiency from general120degree excitation, and it can make phase current similar to sine wave. And then, square wave excitation which used hall sensors and counters is simple way of BLDC drives, and it needs less supply voltage than that to drive BLDC by sine-wave excitation. Therefore, we shows that 150degree square-wave excitation is suitable in high efficiency and simple BLDC drive.

Double winding machine is known that these machines have fault tolerant feature, so it is got much attention especially for application which needs failure tolerance like aircraft, electric vehicle, electric rolling stock, and marine ship. Controlling each winding by independent inverters lets improvement drive characteristics like extending speed range, and reducing torque ripples. But controlling each winding by independent inverters expects letting improvement drive characteristics like extending speed range, and reducing torque ripples, so it is widely considered. In this paper, we use 2 inverter which controlled by 1 microcontroller for driving 10poles-12slots double winding PMSM, operate the motor in situation of current phase difference, and operate the motor in situation when 1 inverter is failure. Then we verify fault tolerance characteristics of the PMSM, and examine improving the PMSM torque characteristics by measuring the torque characteristics. Therefore, it is confirmed that double winding PMSM used in this paper with driving by 2 inverter can keep redundancy and get fault tolerant characteristics, and found that it is possible to reduce torque ripple by inverter phase differential operating. In this test motor, it is found that the torque ripple can reduce by exciting current having 30degree of phase difference to the motor.

In recently, permanent magnet type linear motors (PM-LSM) which could control high speed have attracted attention in the industrial field. Our laboratory is focusing on conveyance system. In the loading and unloading of the luggage of the transport system, the mover to move repeatedly to “stop-and-go”. This drive occurs each time to move the respective processing sections. This work leads to a reduction of transport efficiency. Therefore, we propose parallel synchronous drive. This method synchronizes the mover of the two LSMs. Because both movers in the synchronized state are the same inertia, luggage may be moved without the movers stop. Main line of the motor called “master motor” and another motor called “slave motor”. The master motor's position is passed Slave motor and parallel synchronous drive is run.

The switched reluctance motor (SRM) is suitable for high-speed driving and enables high output. However, it is less efficient than other motors. This is due to an increase in iron loss caused by high speed operation. Therefore, in this paper, we adjusted firing angle and verified that firing angle realizing maximum efficiency exists by changing current waveform and loss. It was confirmed that the firing angle at the maximum efficiency shifted when the number of revolutions was changed. By separating the loss into copper loss and iron loss, we confirmed how they change depending on the firing angle. Through simulation, we compared it with actual machine and verified its validity.

The 10poles-12slots brushless DC motor is superior as AC servo motor by sine-wave excitation, but its characteristics like efficiency get worse by using as BLDC motor by square-wave excitation. However, 150 degree excitation which adjusted excitation angle and excitation phase can increase 3% of efficiency from general 120 degree excitation, and it can make phase current similar to sine wave. And then, square wave excitation which used hall sensors and counters is simple way of BLDC drives, and it needs less supply voltage than that to drive BLDC by sine-wave excitation. Therefore, we shows that 150 degree square-wave excitation is suitable in high efficiency and simple BLDC drive.