Optimal Unity Power Factor Control of Permanent Magnet Synchronous Motor With q-axis Field by Inverse LQ Method

Hiroshi Takami 전력전자학회 2001 JOURNAL OF POWER ELECTRONICS Vol.1 No.2

A synchronous motor (SM) with q-axis special field winding of which the q-axis field-current compensates and cancels armature reaction can be driven at unity power factor under the conditions of transient state as well as steady state. The motor operates in high efficiency in all conditions. However, in order to obtain maximum performance of the motor, it is required that the time constant of armature circuit corresponds to that of q-axis field circuit. Inverse LQ (ILQ) design method on a basis of the pole assignment is suitable for this problem- (1) The time constants of the output responses can be designed for desired specifications, (2) Relations between feedback gains and response of closed loop system are very clear and (3) Optimal solutions can be given by simple procedure of ILQ method without solving the Riccati's equation, compared to the usual LQ design method Accordingly, the ILQ method can make the responses of armature current and q-axis field-current correspond In this paper, it is proved by numerical simulations and experiments that the ILQ method is very effective for optimal regulator design of this plant and realizes a high-performance motor with unity power factor and high efficiency.

Optimal Unity Power Factor Control of Permanent Magnet Synchronous Motor with q-axis Field by Inverse LQ Method

Takami, Hiroshi The Korean Institute of Power Electronics 2001 JOURNAL OF POWER ELECTRONICS Vol.1 No.2

A synchronous motor(SM) with q-axis special field winding of which the q-axis field-current compensates and cancels armature reaction can be driven at unity power factor under the conditions of transient state as well as steady state. The motor operates in high efficiency in all conditions. However, in order to obtain maximum performance of the motor, it is required that the time constant of armature circuit corresponds to that of q-axis field circuit. Inverse LQ(ILQ) design method on a basis of the pole assignment is suitable for this problem:(1) The time constants of the output responses can be designed for desired specifications, (2) Relations between feedback gains and response of closed loop system are very clear and (3) Optimal solutions can be given by simple procedure of ILQ method without solving the Ricaati's equation, compared to the usual LQ design method. Accordingly, the ILQ method can make the responses of armature current and q-axis field-current correspond. In this paper, it is proved by numerical simulations and experiments that the ILQ method is very effective for optimal regulator design of this plant and realizes a high-performance motor with unity power factor and high efficiency.

Robust Current Control for Permanent Magnet Synchronous Motors by the Inverse LQ Method - An Evaluation of Control Performance Using Servo-Locks at Low Speed -

Takami Hiroshi The Korean Institute of Power Electronics 2004 JOURNAL OF POWER ELECTRONICS Vol.4 No.4

This paper describes the optimal current-control of a permanent magnet synchronous motor by the use of robust and simple current controllers, based upon the analytical procedure known as the inverse LQ (ILQ) design method. The ILQ design method is a strategy for finding the optimal gains based on pole assignment without solving the Riccati equation. It is very important to keep the motor in robust servo-lock. By experiments and simulations, we will show that the ILQ optimal servo-system with servo-lock is more insensitive at low speeds to variations in armature inductance than the standard PI servo-system. Variations in armature inductance have the greatest influence on the responses of a servo-system.

Robust Current Control for Permanent Magnet Synchronous Motors by the Inverse LQ Method-An Evaluation of Control Performance Using Servo-Locks at Low Speed

Hiroshi Takami 전력전자학회 2004 JOURNAL OF POWER ELECTRONICS Vol.4 No.4

This paper describes the optimal current-control of a permanent magnet synchronous motor by the use of robust and simple current controllers, based upon the analytical procedure known as the inverse LQ (ILQ) design method. The ILQ design method is a strategy for finding the optimal gains based on pole assignment without solving the Riccati equation. It is very important to keep the motor in robust servo-lock. By experiments and simulations, we will show that the ILQ optimal servo-system with servo-lock is more insensitive at low speeds to variations in armature inductance than the standard PI servo-system. Variations in armature inductance have the greatest influence on the responses of a servo-system.<br/>

Intelligent-CCS Fed Marine-Express Model Train Me03 in Mass-Reduced-Mode

Kinjiro Yoshida,Hiroshi Takami,Hazime Mihara 전력전자학회 1998 ICPE(ISPE)논문집 Vol.- No.-

This paper presents a new high-performance intelligent controlled current-source (CCS) system which can compensate for modelling errors of armature resistance, leakage and magnetizing inductances and for space harmonic components of speed EMF's. A shuttle-motion simulation is presented in the mass-reduced-mode in which an equivalent vehicle weight is reduced, by 40kg, from 47kg to 7kg.<br/> This study provides one of the most important key-tech­nologies in driving practical linear synchronous motor (LSM) Maglev vehicle.<br/>

Levitation Control Experiment at Standstill in PM LSM Controlled-Repulsive Maglev Vehicle

Kinjiro YOSHIDA,Hiroshi TAKAMI,Chiyuki JOZAKI,Shizuo KINOSHITA 전력전자학회 1998 ICPE(ISPE)논문집 Vol.- No.-

This paper proposes a new repulsive-Maglev vehicle in which a vertical type PM linear synchronous motor (LSM) can levitate and propel simultaneously, independently of the vehicle speeds. A compact control method is developed which is based on the concept of controlling individually the levitation system by armature-current and the propulsion system by mechanical load-angle. The levitation-motion control experiments have carried out successfully together with positioning at standstill. The pitching motion has been compensated for very well by using the zero-phase-current control method proposed here.<br/>

Numerical Simulation of Extreme Air Pollution by Fine Particulate Matter in China in Winter 2013

Hikari Shimadera,Hiroshi Hayami,Toshimasa Ohara,Yu Morino,Akinori Takami,Satoshi Irei 한국대기환경학회 2014 Asian Journal of Atmospheric Environment (AJAE) Vol.8 No.1

In winter 2013, extreme air pollution by fine particulatematter (PM2.5) in China attracted much publicattention. In order to simulate the PM2.5 pollution,the Community Multiscale Air Quality model drivenby the Weather Research and Forecasting model wasapplied to East Asia in a period from 1 January 2013to 5 February 2013. The model generally reproducedPM2.5 concentration in China with emission data inthe year 2006. Therefore, the extreme PM2.5 pollutionseems to be mainly attributed to meteorological (weakwind and stable) conditions rather than emissionincreases in the past several years. The model wellsimulated temporal and spatial variations in PM2.5concentrations in Japan as well as China, indicatingthat the model well captured characteristics of thePM2.5 pollutions in both areas on the windward andleeward sides in East Asia in the study period. Inaddition, contribution rates of four anthropogenicemission sectors (power generation, industrial, residentialand transportation) in China to PM2.5 concentrationwere estimated by conducting zero-out emissionsensitivity runs. Among the four sectors, the residentialsector had the highest contribution to PM2.5concentration. Therefore, the extreme PM2.5 pollutionmay be also attributed to large emissions from combustionfor heating in cold regions in China.

Evaluation of Photochemical Pollution during Transport of Air Pollutants in Spring over the East China Sea

Yasuhiro Sadanaga,Tadashi Kobashi,Akie Yuba,Shungo Kato,Yoshizumi Kajii,Akinori Takami,Hiroshi Bandow 한국대기환경학회 2015 Asian Journal of Atmospheric Environment (AJAE) Vol.9 No.4

We conducted intensive observations of ozone, CO, NOx (=NO and NO2), NOy (total odd nitrogen species including particulate nitrate) and total nitrate (the sum of gaseous HNO3 and particulate nitrate) at Cape Hedo, Okinawa, Japan, from 19 March to 3 April, 2009, to investigate ozone production during long-range transport from the Asian continent. Ozone production efficiency (OPE) was used to evaluate photochemical ozone production. OPE is defined as the number of molecules of ozone produced photochemically during the lifetime of a NOx molecule. OPE is calculated by the ratio of the concentration increase of ozone to that of NOz (= NOy -NOx). Average OPE during observation was estimated to be 12.6±0.5, but concentrations of ozone increased nonlinearly with those of NOz. This non-linearity suggests that OPE depends on air mass origin and NOz concentrations. There were very different values of OPE for the same air mass origin, so that only the air mass origin alone does not control OPE. OPE was low when NOz concentration was high. We examined the correlation between NOz and CO/NOy ratios, which we used instead of the ratio of nonmethane hydrocarbons (NMHCs) to NOx. The CO/NOy ratios decreased with increasing NOz concentrations. These results indicate that competition reactions of OH with NMHCs and NO2 are the rate determining steps of photochemical ozone production during longrange transport from the Asian continent to Cape Hedo, for high concentrations of nitrogen oxides.