The switched reluctance motor (SRM) is a type of motor doubly salient with phase coils mounted around diametrically opposite stator poles. There are no windings or permanent magnets on the rotor. The rotor is basically a piece of (laminated) steel and its shape forms salient poles. The stator has concentrated coils.
2. Construction of SRM
Stator:
• It is built by stacking
suitably punched silicon
laminations to the
appropriate length.
• It has salient poles.
• The poles carry concentric
windings.
• The coils on opposite poles
are connected in series to
form stator phases.
• The overlapping of coils is
avoided to minimise the
mutual inductance between
the phases.
• End connections should be
made very short.
3. Construction of SRM
Rotor:
• The rotor contains no winding or permanent magnet.
• It is built up of steel laminations.
• The laminations are stacked to the shaft.
• It is due to this mechanical simplicity that the cost of
SRM is promisingly low, which attracts many industries
to use it.
4. Principle of Operation
• Smallest magnetoresistance principle.
• The magnetic flux is always closed along the path
of least reluctance.
• When the two
electromagnets are
energized, the rotor
will experience a very
strong force to align
with the magnetic
field.
7. Switched Reluctance Motor
Advantages:
• High Efficiency
• Good performance like
• Torque to inertia ratio
• Maximum operating Speed
• Simple in construction
Application:
• Its availability variable size, power and speed ranges
• Ability to operate in four quadrant
• Because of these features it is widely used as a variable
speed drives.
8. Switched Reluctance Motor
Similarity:
• It is similar to Variable Reluctance Stepper
Motor.
• Alternative:
• It is a better alternative to DC series motor and
variable speed induction motor drives.
