| 摘要 |
FIELD: electrical engineering. SUBSTANCE: method for pressing core of electric motor stator which has slots for winding and is made from steel sheets which are bound by means of pressing plates and clamping members involves detection of processing pressure by means of sequential mechanical pulse excitation in several sections along core length, measurement of current values of natural frequencies in these sections, measurement of average temperature of core and clamping members, calculation of processing pressure P in corresponding sections of corresponding using equation P = (f<SP>2</SP>/f<CHF>2@o</CHF>)P<SB>o</SB>+alpha<SB>c</SB>(t<SB>c</SB>-t<SB>oc</SB>)E<SB>c</SB>-alpha<SB>cm</SB>(t<SB>cm</SB>-t<SB>ocm</SB>)E<SB>c</SB>, E<SB>c</SB>, where f is first natural frequency of stator core, f0 is first natural frequency of stator core during first measurement, P0 is pressure which affects core during first measurement, alpha<SB>c</SB> is index of core thermal expansion, alpha<SB>cm</SB> is index of clamping members thermal expansion, t<SB>c</SB> is current core temperature, t<SB>co</SB> is temperature of core during first measurement, t<SB>c</SB> is current temperature of clamping members, t<SB>ocm</SB> is temperature of clamping members during first measurement, E<SB>c</SB> is modulus of core elasticity which is calculated using equation E<SB>c</SB>= (f<SP>2</SP>/f<CHF>2@o</CHF>)E<SB>co</SB>, E<SB>co</SB>= 2piM(R<SB>2</SB>+R<SB>1</SB>)f<CHF>2@o</CHF>/(R<SB>2</SB>+R<SB>1</SB>) , i.e. <EMI ID=0.239 HE=9 WI=54 TI=CHI>, where E<SB>co</SB> is modulus of core elasticity during first measurement, M is weight of core back edge (in kg), R<SB>1</SB> is radius of stator core along slot bottom, R<SB>2</SB> is radius of stator core along back edge. EFFECT: increased reliability of assessment of density of bladed core, increased functional capabilities, increased efficiency of operations, simplified design. 3 dwgb
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