Cross-reference to related application
[0001] This application is a patent of addition of IN application No. 202341045350
filed on July 6, 2023, the disclosure of which is hereby expressly incorporated.
5
Field of the invention
[0002] The present invention relates generally to the field of reluctance motors. More
particularly, the present invention relates to an improved structure of a sintered hybrid
10 switched reluctance motor.
Background of the invention
[0003] Conventionally, electric motors have been a part of the industry since ages.
15 Electric motors form an important part of our day-to-day lives and dependency on motors
has been ever increasing. Electric motors are used not only in industries but also in domestic
applications. Electric motors are used in applications such as pumps, compressors, blowers,
fans, refrigerators, air-conditioners, drilling machines, lathe machines and power tools, etc.
Application of electric motors in electric vehicles is witnessing an exponential growth in the
20 past few years.
[0004] There have been continuous developments and improvements made to electric
motors to not only improve overall efficiency, but also to minimise cost involved in
manufacturing and in maintenance of the electric motors. Reluctance motors have been the
25 latest improvement made in the field of electric motors that offer a wide range of advantages.
Furthermore, Switched Reluctance Motors (SRM) offer added flexibility during operation
of the SRMs. However, the SRMs available in the market have several shortcomings in terms
of size and generated torque.
30 [0005] Primarily, volumetric size of the SRMs available in the market is comparatively
larger for output that they are designed to produce. Furthermore, the SRMs employ a large
quantity of copper windings which increases cost involved in manufacturing of the SRMs.
In conventional SRMs that are currently available in market, a rotor of the SRM is formed
by stacking plurality of lamination sheets that are radially stamped to define several full
35 circular profiles. The full circular profiles are configured to shape the flux as per
requirement. Each of the semi-circular profiles are held together via a small connecting
profile. Also, lamination of conventional SRMs is in a plane that is perpendicular to the axis of the SRM. The flux paths in the conventional SRMs have a long path in back-iron of the
SRM that tends to increase reluctance and has a detrimental effect on torque producing
capability. Therefore, there is a need for the SRM that has a shorter flux path.
5 [0006] Typically, in electric motors if the stator is positioned outside it is called a
centre drive motor. However, if the stationary member is inside and rotating member is
outside, like in a ceiling fan, then it is called a hub motor. An in-wheel motor is used for
transmission in electric two-wheeler where shaft is stationary and body is rotating. In the
electric motor, for every one activation, there are two long loops created of magnetic flux
10 path and distance that magnetic flux has to travel is very large. Also, the SRMs are heavier
in terms of weight that poses as a disadvantage. Also, the SRMs available in the market have
a complex structural design that employs a large number of components in manufacturing.
This not only increases overall cost of manufacturing but also affects maintenance of the
SRMs and increases weight of the SRM. Conventional SRMs also generates mild to medium
15 whining noise during their operation, which is not desirable.
[0007] Typically, sintering is a process of bonding powder particles into a solid mass
through heat and pressure, without melting material. This technique allows for fabrication
of complex shapes and components from HSRMs, which are challenging to manipulate due
20 to their high melting points and brittleness. Sintering parameters like
temperature, pressure, and dwell time need to be carefully controlled to achieve optimal
density, strength, and microstructure in the final product.
[0008] In light of the above-mentioned drawbacks, there is a need for an improved
25 hybrid switched reluctance motor that reduces noise and has an improved torque profile.
Also, there is a need for an improved structure of a sintered hybrid switched reluctance
motor. There is a need for a construction of SRM that decreases reluctance, magneto motive
force (mmf) requirement, flux density leading to lesser hysteresis and eddy losses that
improves efficiency and performance of the SRM.
30
Summary of the invention
[0009] In various embodiments of the present invention, an improved structure of a
sintered Hybrid Switched Reluctance Motor (HSRM) is provided. The HSRM (400, 500,
35 1102) comprises a stator entity (502,1116) comprising a stator (606a, 606b) and E shaped
stator poles (614a,614b) forming a single stator entity (502). The stator entity (502)
comprises a first set of windings (1104, 608a, 608b) and a second set of windings (1108,
610b) and a rotor entity (504, 1112) comprising a rotor (716) and I shaped rotor poles (710,
1112) forming a single rotor entity (720). The first set of windings (608a, 608b,1104) and
the second set of windings (610b, 1108) are energized for driving the sintered HSRM (400,
5 500, 1102) to support redundancy and to improve torque density of the sintered HSRM
(400, 500, 1102) based on the type of system in which the sintered HSRM (1102) is
deployed. Flux generated by the stator windings (608a, 608b, 610b, 1104,1108) around the
E shaped stator poles (614a,614b) traverses a three-dimensional path through the single
stator entity (502) of the HSRM (400, 500, 1102).
10
[0010] In an embodiment of the present invention, the sintered HSRM (400, 500,
1102) is a sintered powder metallurgy based HSRM constructed using composite soft
magnetic core material.
15 [0011] In an embodiment of the present invention, the stator entity (502) receives the
stator windings (608a, 608b,610b, 1104, 1108) and longitudinal sides of the E shaped poles
(614a,614b) are aligned parallel to a motor axis of the sintered HSRM (400, 500, 1102)
and the I shaped rotor poles (710) are arranged radial to the motor axis of the sintered
HSRM (400, 500, 1102). A central axis of the stator windings (608a,
20 608b,610b,1104,1108) is perpendicular to the motor axis leading to creation of a plane of
a flux along the motor axis while maintaining the plane of flux in air gaps of the HSRM
(400, 500, 1102) to be radial in nature.
[0012] In an embodiment of the present invention, a first set of windings (1104)
25 resides in a first E section stator (1106) that is controlled by a first controller (1118a) and
a second set of windings (1108) resides in a second E section stator (1110) that is controlled
by a second controller (1118b).
[0013] In an embodiment of the present invention, the first set of windings (608b) is
30 energized by a first controller (616b) and the second set of windings (610b) is energized
by a second controller (618b).
[0014] In an embodiment of the present invention, the first set of windings (608b)
and the second set of windings (610b) are connected in parallel. The first set of windings (608b) and the second set of windings(610b) are energized either by a first controller
(616b) or a second controller (618b).
[0015] In an embodiment of the present invention, the first set of windings (1104) in
5 a first E section stator (1106) and the second set of windings (1108) in a second E section
stator (1110) are connected in parallel. The first set of windings (1104) and the second set
of windings (1108) are energized either by a first controller (1118a) or by a second
controller (1118b).
10 [0016] In an embodiment of the present invention, the first set of windings (1104) in
a first E section stator (1106) and the second set of windings (1108) in a second E section
stator (1110) are connected in series. The first set of windings (1104) and the second set of
windings (1108) are energized either by a first controller (1118a) or by a second controller
(1118b)

We Claim
1. An improved structure of a sintered Hybrid Switched Reluctance Motor (HSRM)
comprising:
5 a stator entity (502,1116) comprising a stator (606a, 606b) and E shaped
stator poles (614a,614b) forming a single stator entity (502), wherein the stator
entity (502) comprises a first set of windings (1104, 608a, 608b) and a second set
of windings (1108, 610b), the first set of windings (1104, 608a, 608b) and the
second set of windings (1108, 610b) are energized for driving the sintered HSRM
10 (400, 500, 1102) to support redundancy and to improve torque density of the
sintered HSRM (400, 500, 1102) based on the type of system in which the sintered
HSRM (400, 500, 1102) is deployed; and
a rotor entity (504, 1112) comprising a rotor (716) and I shaped rotor poles
(710, 1112) forming a single rotor entity (720), wherein flux generated by the
15 stator windings (608a, 608b, 610b, 1104, 1108) around the E shaped stator poles
(614a,614b) traverses a three-dimensional path through the single stator entity
(502) of the sintered HSRM (400, 500, 1102).
2. The sintered HSRM as claimed in claim 1, wherein the sintered HSRM (400, 500,
20 1102) is a sintered powder metallurgy based HSRM constructed using composite
soft magnetic core material.
3. The sintered HSRM as claimed in claim 1, wherein the stator entity (502) receives
the stator windings (608a, 608b, 610b,1104, 1108) and longitudinal sides of the E
25 shaped poles (614a,614b) are aligned parallel to a motor axis of the sintered
HSRM (400, 500, 1102) and the I shaped rotor poles (710) are arranged radial to
the motor axis of the sintered HSRM (400, 500, 1102) and wherein a central axis
of the stator windings (608a, 608b, 610b, 1104, 1108) is perpendicular to the motor
axis leading to creation of a plane of a flux along the motor axis while maintaining
30 the plane of flux in air gaps of the sintered HSRM (400, 500, 1102) to be radial in
nature.
4. The sintered HSRM as claimed in claim 1, wherein a first set of windings (1104)
resides in a first E section stator (1106) that is controlled by a first controller (1118a) and a second set of windings (1108) reside in a second E section stator
(1110) that is controlled by a second controller (1118b).
5. The sintered HSRM as claimed in claim 1, wherein the first set of windings (608b)
5 is energized by a first controller (616b) and the second set of windings (610b) is
energized by a second controller (618b).
6. The sintered HSRM as claimed in claim 1, wherein the first set of windings (608b)
and the second set of windings (610b) are connected in parallel, and wherein the
10 first set of windings (608b) and the second set of windings(610b) are energized
either by a first controller (616b) or a second controller (618b).
7. The sintered HSRM as claimed in claim 1, wherein the first set of windings (608b)
and the second set of windings (610b) are connected in series, and wherein the first
15 set of windings (608b) and the second set of windings (610b) are energized either
by a first controller (616b) or a second controller (618b).
8. The sintered HSRM as claimed in claim 1, wherein the first set of windings (1104)
in a first E section stator (1106) and the second set of windings (1108) in a second
20 E section stator (1110) are connected in parallel, and wherein the first set of
windings (1104) and the second set of windings (1108) are energized either by a
first controller (1118a) or by a second controller (1118b).
9. The wintered HSRM as claimed in claim 1, wherein the first set of winding (1104)
25 in a first E section stater (1106) and the second set of winding (1108) in a second
E section stater (1110) are connected in series, and wherein the first set of winding
(1104) and the second set of winding (1108) are energized either by a first
controller (1118a) or by a second controller (1118b).