Rotating electrical machine including a magnetic position sensor

Patent metadata

Field	Value
Publication number	US-10873248-B2
Application number	US-201716465480-A
Country	US
Kind code	B2
Filing date	Oct 30, 2017
Priority date	Dec 1, 2016
Publication date	Dec 22, 2020
Grant date	Dec 22, 2020

Abstract

The invention relates to a rotary electrical machine (100) with an integral magnetic sensor (101) of the angular position of the rotor (150). The sensor includes a rotary part (108) with magnet (102) fixed to the end (160b) of the rotation shaft (160) at the rear of the machine, facing a fixed part (103) including Hall effect sensors and mounted on a fixed support (106) connected to the frame of the machine. The machine includes a bearing (104) centered on the axis (X), separating the rotary and fixed parts of the sensor. This bearing, fixed to the shaft and to the metal support of the fixed part of the sensor, and preferably in contact with the rotary part, constitutes a new mechanical reference close to the sensor. The invention provides accurate and robust position information independently of mechanical and magnetic disturbances to which the shaft may be subjected.

First claim

The invention claimed is:

1. A rotary electric machine including:
a stator disposed in a frame, including windings;
a rotor including a body fixed to a rotatably mounted shaft rotatably mounted in the stator to rotate about an axis;
a first bearing supporting an end of the rotatably mounted shaft driving a load;
a second bearing supporting an end of the rotatably mounted shaft opposite the end driving the load;
a front flange disposed at a first end of the frame and including a first housing in a median part thereof for receiving the first bearing;
a rear flange disposed at a second end of the frame opposite the first end and including a second housing in a median part for receiving the second bearing;
the front and rear flanges each having an internal face and an external face,
a magnetic position sensor for measuring the angular position of the rotor during rotation of the rotatably mounted shaft, the position sensor including:
a rotary part comprising a magnet fixed to the end of the rotatably mounted shaft opposite the end driving the load which rotates with the rotatably mounted shaft during the rotation of the rotatably mounted shaft;
a fixed part including Hall effect sensors and means for transmitting output signals from the sensors, the fixed part facing the rotary part and being mounted on a fixed metal support connected to the frame of the machine;

the rotary part and the fixed part of the position sensor being separated by a third bearing centered on the axis, the third bearing being fixed on the end of the rotatably mounted shaft opposite the end driving the load and to walls of an opening formed in the fixed metal support adapted for passing the end of the rotatably mounted shaft including the rotary part.

2. An electrical machine according to claim 1 , wherein the third bearing contacts the rotary part.

3. An electrical machine according to claim 1 , wherein the rotary part includes an insert housed in a cavity formed at the end of the rotatably mounted shaft opposite the end driving the load, the cavity including an opening toward an exterior of the machine, the insert being on a side of the opening of the cavity formed at the end of the rotatably mounted shaft.

4. An electrical machine according to claim 2 , wherein the rotary part includes an insert housed in a cavity formed at the end of the rotatably mounted shaft opposite the end driving the load, the cavity including an opening toward an exterior of the machine, the insert being on a side of the opening of the cavity formed at the end of the rotatably mounted shaft.

5. An electrical machine according to claim 3 , wherein the insert of the rotary part of the position sensor is made of nonmagnetic material.

6. An electrical machine according to claim 4 , wherein the insert of the rotary part of the position sensor is made of nonmagnetic material.

7. An electrical machine according to claim 1 , wherein the third bearing is formed of a ferromagnetic material.

8. An electrical machine according to claim 1 , wherein the third bearing comprises rolling members, an external race fixed to the walls of the opening of the metal support and an internal race fixed to the end of the rotation shaft opposite the driving end and in contact with the rotary part of the sensor.

9. An electrical machine according to claim 1 , wherein the fixed metal support of the fixed part of the sensor has an internal face facing toward the rear flange and an external face oriented toward the exterior of the machine, the external face including a plane surface at a periphery of the opening of the metal support, which is in contact with the fixed part of the position sensor.

10. An electrical machine according to claim 1 , comprising a cooling system providing external cooling for cooling the frame and the front and rear flanges, the external cooling including an external fan fastened to the rotatably mounted shaft and disposed between the external face of the rear flange and the third bearing direct outside air along the frame in a direction of the front flange.

11. An electrical machine according to claim 10 , wherein:
the frame has an external surface including cooling fins elongated along an axis parallel to the axis of the rotation shaft; and
the rear flange has a central ring connected to a cylindrical peripheral part and at least one opening disposed between the central ring and the peripheral part of the rear flange to direct the outside air from the external fan into the passages formed by the cooling fins on an external surface of the frame.

12. An electrical machine according to claim 10 , in which the external fan includes an outside air impellor mounted on the rotatably mounted shaft between the external face of the rear flange and the third bearing and in which the fixed metal support is connected to the frame by being fixed to a protection plate covering the external fan, the protection plate including orifices for entry of the outside air and being fixed to the peripheral part of the rear flange.

13. An electrical machine according to claim 12 , wherein the frame and the front and rear flanges form a sealed casing and in which the cooling system further includes a pair of internal fans disposed inside the frame to create a flow of air inside the frame when the rotor rotates, each fan being fixedly mounted on the rotatably mounted shaft between a body of the rotor and a bearing and an internal face of each of the front and rear flanges includes fins on a peripheral part of first and second housings of the flanges to orient the flow of air and to capture heat of the flow of air.

14. An electrical machine according to claim 1 , wherein the magnetic position sensor integral with the machine has a protection index IP67 in accordance with European standard EN 60529.

15. An electrical machine according to claim 1 having an inclusive power rating between 20 kW and 75 kW.

16. An electrical machine according to claim 1 wherein the electrical machine is a synchronous reluctance electrical machine.

Assignees

• Ifp Energies Now
• Mavel Srl

Inventors

• Dib Wissam
• Favre Luca
• Bettoni Davide

Classifications

• F16C2370/00

  Apparatus relating to physics, e.g. instruments · CPC title

• H02K9/08

  by gaseous cooling medium circulating wholly within the machine casing (H02K9/10 takes precedence) · CPC title

• H02K5/18

  with ribs or fins for improving heat transfer · CPC title

• F16C2380/26

  Dynamo-electric machines or combinations therewith, e.g. electro-motors and generators · CPC title

• H02K7/08

  Structural association with bearings · CPC title