Electricity: motive power systems – Reciprocating or oscillating motor – Energizing winding circuit control
Patent
1991-11-29
1994-01-18
Wysocki, Jonathan
Electricity: motive power systems
Reciprocating or oscillating motor
Energizing winding circuit control
318439, 318254, H02P 700
Patent
active
052802221
DESCRIPTION:
BRIEF SUMMARY
CROSS-REFERENCE TO RELATED APPLICATION
The invention of this application is related to that of our copending patent application Ser. No. 07/805,154, filed Dec. 11, 1991.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a motor or a position indicator (position sensor) comprising an apparatus or method for controlling a brushless electric motor. The term motor is here understood to mean also e.g. a linear motor, whose position is to be detected. Both a rotary motor and a linear motor has as its movable part a rotor.
2. Description of the Related Art
Different types of position sensors are known and are e.g. used for determining the position of motor elements. In most cases there is an associated linear acting principle for a rotary acting principle. The most important classes of such position sensors or indicators are based on the following:
Position sensors with direct contact with the movable element:
Position sensors with contactless operating means: photosensors, optical interference sensors sensors (based on Hall generators), Wiegand effect sensors, magnetostrictive sensors, magnetoresistive sensors differential transformers microwave distance measuring equipment.
This list only represents the most important classes and only constitutes a small selection of the sensors used in practice for rotary or linear measuring functions. Hereinafter the position determination or detection processes are described to the extent that they are used both in linear or rotary acting electric motors.
Reference is subsequently made to the electrical angular position. The latter is measured in electrical degrees, e.g. 20.degree. el. In the case of a bipolar motor with a number of poles p=1, the electrical degrees of the rotor position correspond to the mechanical degrees. In the case of a four pole motor (p=2), on rotating by 360.degree. mech, the rotor passes through in all p.times.360.degree. el, i.e. 720.degree. el, etc.
The described measuring methods agree within a range of 360.degree. el, i.e. they determine the electrical angular position of the rotor. For example, with a four-pole motor (p=2), the measured electrical angular position 90.degree. el represents a rotor position of 90.degree. el or (90+360).degree. el, which is unimportant for the commutation control.
Besides methods, which carry out a position determination in motors through external sensors (e.g. using Hall effect sensors, light barriers and magnetoresistive sensors), there are methods whose function is to determine the position of a motor by components within the motor. These methods can essentially be subdivided into two classes.
In a first class use is made of the generator characteristics of motor coils and there is a dynamic position determination. As a function of the level or integral of the generated voltage over time, conclusions can be drawn regarding the rotor position.
This class is characterized by different use fields and widely varying embodiments. As an example of the relevant prior art reference is made to the following patent literature:
It is unimportant whether the magnetic field of the rotor is generated by permanent magnets or by electric magnets. To the extent that reference is made here and hereinafter to permanent magnets, it always includes electric magnets, unless indicated otherwise.
In the same way it is possible to functionally interchange rotating and stationary parts of the electric motor, i.e. the invention is suitable for internal rotor-type motors, external rotor-type motors, motors with a planar air gap, motors in which the permanent magnetic rotor rotates and the motor winding is stationary or conversely motors in which the motor winding rotates and is e.g. supplied across slip rings and the permanent magnetic part is stationary and other motor construction types, in the manner illustrated by examples hereinafter.
In a second class the position determination methods are based on the fact that the motors in question are not ideal, i.e. despite constant, distinct electrical quantiti
REFERENCES:
patent: 4528486 (1985-07-01), Flaig et al.
patent: 4531079 (1985-07-01), Muller
patent: 4712050 (1987-12-01), Nagasawa et al.
patent: 4743815 (1988-05-01), Gee et al.
patent: 4814677 (1989-03-01), Plunkett
patent: 4893071 (1990-01-01), Miller
patent: 4928043 (1990-05-01), Plunkett
patent: 4958115 (1990-09-01), Miller
patent: 5012166 (1991-04-01), Ushijima et al.
patent: 5017845 (1991-05-01), Carobolante et al.
patent: 5028852 (1991-07-01), Dunfield
patent: 5047699 (1991-09-01), Rozman et al.
Schroedl, M. and Stefan, T., "Algorithm for Mathematical Detection . . . ", Antriebssysteme fuer die Geraete- und Kraftfahrzeugtechnik, Bad Nauheim, Germany, VDE-Verlag Berlin-Offenbach, pp. 48-54 (1988).
Schroedl, M., "Detection of the Rotor Position of a Permanent Magnet Synchronous Machine at Standstill", Proc. ICEM, Pisu (Italy), pp. 195-197 (1988).
Schroedl, M., "Operation of the Permanent Magnet Synchronous Machine Without a Mechanical Sensor", Proc. IEE International Conference on Power Electronics and Variable Speed Devices, London, pp. 51-56 (1990).
P. P. Acarnley et al., "Detection of Rotor Position in Stepping and Switched Motors by Monitoring of Current Waveforms", IEEE Transaction on Industrial Electronics, vol. IE-32, No. 3, Aug. 1985, pp. 215-222.
Hermann Micheal
Muller Uwe
von der Heide Johann
Papst Motoren GmbH & Co. KG
Wysocki Jonathan
LandOfFree
Apparatus and method for controlling brushless electric motors a does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus and method for controlling brushless electric motors a, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus and method for controlling brushless electric motors a will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1138386