异步电动机的性能指标包括效率、功率因数、起动转矩、最大起动转矩和起动电流等。这些指标与电动机定子线圈的质量直接有关,特别是效率和功率因数。因此,电动机定子线圈的修理质量必须予以重视。一、两个基本关系公式每极每相串联匝数:...异步电动机的性能指标包括效率、功率因数、起动转矩、最大起动转矩和起动电流等。这些指标与电动机定子线圈的质量直接有关,特别是效率和功率因数。因此,电动机定子线圈的修理质量必须予以重视。一、两个基本关系公式每极每相串联匝数:W=(10~6·U)/(2.22K·B·Si)每相电流:I=a·N·S·J(2)式中:U-定子每相电压;K-绕组系数;B-磁通密度;Si-铁芯截面积;a-线圈并联路数;N 导线并绕根数;S 导线截面积;J—电流密度。由上述两个公式可知,定子线圈的匝数 W 与一定的铁芯截面磁通密度 B 有关;每相电流 I展开更多
Let Z=( Zt)t≥0 be a Bessel process of dimension δ( δ〉0) starting at zero and let K(t) be a differentiable function on [0,∞) with K(t)〉0 (A↓t≥0). Then we establish the relationship between L^p-norm o...Let Z=( Zt)t≥0 be a Bessel process of dimension δ( δ〉0) starting at zero and let K(t) be a differentiable function on [0,∞) with K(t)〉0 (A↓t≥0). Then we establish the relationship between L^p-norm of log^1/2(1 +δJτ) and L^p-norm of sup Zt[t+k(t)]^-1/2 (0≤t≤τ) for all stopping times τ and all 0〈p〈+∞.As an interesting example, we show that ||log^1/2(1+δLm+1(τ)||p and ||supZtП[1+Lj(t]^1/2||p (0≤j≤m,j∈Z;0≤t≤τ) are equivalent with 0〈p〈+∞ for all stopping times rand all integer numbers m, where the function Lm(t) (t≥0) is inductively defined by Lm+1(t)=log[ 1 +Lm(t)] with L0(t)= 1.展开更多
文摘异步电动机的性能指标包括效率、功率因数、起动转矩、最大起动转矩和起动电流等。这些指标与电动机定子线圈的质量直接有关,特别是效率和功率因数。因此,电动机定子线圈的修理质量必须予以重视。一、两个基本关系公式每极每相串联匝数:W=(10~6·U)/(2.22K·B·Si)每相电流:I=a·N·S·J(2)式中:U-定子每相电压;K-绕组系数;B-磁通密度;Si-铁芯截面积;a-线圈并联路数;N 导线并绕根数;S 导线截面积;J—电流密度。由上述两个公式可知,定子线圈的匝数 W 与一定的铁芯截面磁通密度 B 有关;每相电流 I
基金Project supported by the National Natural Science Foundation of China (No. 10571025) and the Key Project of Chinese Ministry of Education (No. 106076)
文摘Let Z=( Zt)t≥0 be a Bessel process of dimension δ( δ〉0) starting at zero and let K(t) be a differentiable function on [0,∞) with K(t)〉0 (A↓t≥0). Then we establish the relationship between L^p-norm of log^1/2(1 +δJτ) and L^p-norm of sup Zt[t+k(t)]^-1/2 (0≤t≤τ) for all stopping times τ and all 0〈p〈+∞.As an interesting example, we show that ||log^1/2(1+δLm+1(τ)||p and ||supZtП[1+Lj(t]^1/2||p (0≤j≤m,j∈Z;0≤t≤τ) are equivalent with 0〈p〈+∞ for all stopping times rand all integer numbers m, where the function Lm(t) (t≥0) is inductively defined by Lm+1(t)=log[ 1 +Lm(t)] with L0(t)= 1.
文摘A new dispersive relation is found and a half-pow tormulas for the generalize Miodek equation under the deeaying conditions at infinity are obtained.