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Electrical Engineering

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AC Steady State Power

Reducing Reactive Power in AC Loads

Description

Power factor correction helps AC systems use electrical power more efficiently. In a factory circuit, transmitted power includes apparent power, which is made of active power and reactive power. Power factor is the ratio of real power, measured in kW, to apparent power, measured in kVA. It shows how much of the supplied powe...

Transcript

向工厂传输电能时涉及有功功率和无功功率的传输。有功功率与总功率的比值定义为功率因数。

低功率因数意味着电感性电气负载吸收更多的无功功率,导致滞后功率因数降低。这会在负载上产生较大的电压降和热损耗,增加电力成本并降低系统效率。

通过在负载两端并联自调谐电容器等补偿阻抗,可以提高功率因数。这种方法可使功率因数尽可能接近于1。

通过功率三角形可以演示添加电容器的效果。通过分析原始电路的功率三角形,可以确定有功功率和无功功率。

增加容性负载可在不改变有功功率的情况下减小功率因数角。根据新的功率三角形,可计算出校正后的无功功率值。

这种无功功率的降低是由并联电容引起的。通过重新审视无功功率的表达式,可确定并联电容器的数值。