find actuation time of the electromagnet.
1.2. Completing of the equivalent circuit
first step is to set up equivalent magnetic circuit without taking into account reluctance of iron subcircuits. The scheme is represented on the Figure 1.2.MMF that is produced by flowing current through the coil is drawing as the source of power. The magnetic resistances of operating and parasitic air gaps are drawn as resistors.is the magnetic resistance of the operating air-gap. Rm2 and Rm3 are the magnetic resistances of the parasitic air-gaps. br/>
1.2. - Equivalent circuit
1.3. The permeance of the air-gaps determination
permeance of the operating air-gap is determined according to the method of probable flux passes. The fluxes in this air-gap are shown on the Figure 1.3. br/>
1.3.1. - Fluxes flowing between core and armature (1) and between yoke and armature (2)
magnetic permeances of the operating air-gap by the method of probable fluxes can be calculated
Ој0 - is magnetic constant, or vacuum permeability,;
? п - is the value of the operating air-gap, m.
В
where? п - is the value of the operating air-gap, m.lets find the front magnetic flux permeance of the operating air-gap:
В
. it is possible to find the full magnetic permeance of the operating air-gap:
,
.
The next step is to find the magnetic permeance of parasitic air-gap? 2. It can be found using specific permeance for coaxial cylinders [5]. The flux through? 2 can be calculated without taking into account fluxes of bulding, because the dimensions of the pole are more than the air-gap in 240 times. br/>В
where d2 - is the value of the parasitic air-gap, m.
. lets find the permeance of the parasitic air-gap between the yoke and the armature using Roters method.first, lets find square of a high yoke surface:
В
; front magnetic flux permeance of the parasitic air-gap is determined:
;
.
For ?? 1z1 the formula of half-ring is used [5]:
В
,
For?? 1p1 the formula of half-cylinder is used [5]:
В
В
For?? 1p2 the formula of quarter-cylinder is used [5]:
В
,
For?? 1z2 the formula of quarter-ring is used [5]
В
, total permeance of the parasitic air-gap is found:
В
В
1.4. Determination of magnetic flux
it is necessary to find the flux of the pole:
В
where B? - Is magnetic induction, T;? - Is the pole face area, m2;
? вп...
