The frequency of alternating current refers to the number of times the voltage or current of alternating current changes per unit of time. The frequency unit is Hertz (Hz); the energy storage power frequencies are 50Hz and 60Hz. The AC frequency has a great influence on the power system and electrical equipment.

    1. Difference between the AC frequency of 50Hz and 60Hz

    50Hz and 60Hz are the standard frequencies used in household electrical systems in Europe and the United States, respectively. The main differences are that they are:

    The 50Hz cycle is longer than the 60Hz cycle, and the voltage and current change more slowly

    The power formula for AC is P = UI cosΦ, where U is the voltage, I is the current, and cos Φ is the power factor. When U and I are constant, reducing Φ can increase the power factor, thus improving the power utilization efficiency. At the same voltage and current, the Φ value of 50Hz is larger, so the power factor is lower and the power utilization efficiency is lower.

    Light output was approximately 16.7% lower at 50Hz than at 60Hz, causing visual flicker and vertigo.

    2. The influence of AC frequency on energy storage power supply

    In the power system, the rotational speed of the alternator is proportional to the output voltage. Voltage fluctuation due to load change can cause electrical equipment failure or damage if the frequency is unstable. But the power equipment operating in Europe and elsewhere must adapt to 50Hz, and those operating in the United States and elsewhere must adapt to 60Hz, which limits the connectivity of the international power system.

    3. Influence of AC frequency of energy storage power supply on electrical equipment

    The frequency of the alternating current in the energy storage power supply has an impact on the working stability, safety and energy saving of the electrical equipment. Some electrical devices are designed for specific frequencies, such as a 60Hz electric motor and a 50Hz transformer. If the electrical equipment is connected to the wrong frequency of energy storage power supply, it will make the equipment vulnerable to damage, and even cause safety problems such as fire. When using electrical equipment, pay attention to its rated frequency and ensure that the connected energy storage power supply matches it.