江苏春晨电缆有限公司生产JBYH电机引接线 电机引出线 春晨,
电感元件的交流电路
AC circuit of inductive element
下图a交流电路是由线性理想电感元件构成的,其电流、电压的参考方向已标在图中。
The AC circuit in figure a below is composed of linear ideal inductive elements, and the reference directions of current and voltage are marked in the figure.
电感元件的交流电路
AC circuit of inductive element
电压与电流的关系
The relationship between voltage and current
当通过电感的电流为i=Imsinωt=I√2 sinωt时,并以它为参考量,由《电路中的无源元件:电阻、电容和电感》一文中的下式:JBYH电机引接线 电机引出线 春晨
When the current passing through the inductor is I = imsin ω t = I √ 2Sin ω T, and with it as the reference quantity, the following formula is given in the article "passive components in circuits: resistance, capacitance and inductance":
电感两端的电压
Voltage at both ends of inductance
可得电感两端的电压为:
The voltage at both ends of the inductance can be obtained as follows:
电感电压计算公式
Calculation formula of inductive voltage
由上式可见,电感上电压与电流是同频率的正弦量;电压与电流的数量关系为:
It can be seen from the above formula that the voltage and current on the inductance are sinusoidal quantities of the same frequency; the quantitative relationship between the voltage and current is as follows:
电感中电压与电流的关系公式
The relation formula of voltage and current in inductance
XL称为电感的感抗,当频率的单位为Hz,电感的单位为H时,感抗的单位为Ω。
XL is called inductive reactance. When the unit of frequency is Hz and the unit of inductance is h, the unit of inductive reactance is Ω.
由上式可见,感抗反映了电感元件对交流电流阻碍能力的大小,它与L、f成正比。在相同电压作用下,L越大说明其产生的自感电动势越大(eL=-L(di/dt)),则对电流的阻碍能力越大,电流就越小;频率越高,即通过电感的电流变化率越大,其产生的自感电动势越大,电流也就越小。所以一个电感为L的线圈,当通过频率不同的交流电流时,对电流的阻碍作用是不同的,即XL的数值是不同的。频率越高,XL越大,电流越难通过。如果f=0,则XL=0,说明直流电流很容易通过电感元件。直流电路中若有电感元件,电路在稳态时电感元件对电流没有阻碍作用,可视为短路。
It can be seen from the above formula that the inductive reactance reflects the blocking capacity of the inductive element to the AC current, which is proportional to L and F. Under the same voltage, the greater L is, the greater the self induced electromotive force (EL = - L (di / DT)), the greater the resistance to the current, the smaller the current; the higher the frequency is, the greater the current change rate through the inductance, the greater the self induced electromotive force and the smaller the current. Therefore, when a coil with L inductance passes through alternating current with different frequency, its blocking effect on the current is different, that is, the value of XL is different. The higher the frequency, the larger the XL, the more difficult the current is to pass through. If f = 0, XL = 0, it means that DC current is easy to pass through inductive element. If there is inductor in DC circuit, it can be regarded as short circuit if inductor has no effect on current in steady state.
电感电路中的电压、电流波形见上图b所示。
The voltage and current waveforms in the inductive circuit are shown in Figure B above.
电压与电流的相位关系是:电压超前电流90°,或电流落后电压90°。用相量形式表示,电压与电流的关系有:
The phase relationship between voltage and current is: voltage is 90 ° ahead of current, or current is 90 ° behind voltage. In the form of phasor, the relationship between voltage and current is as follows: