The AC series resonance system under UHV power can help many power workers conduct various power tests more conveniently.
The circuit composed of inductors and capacitors will oscillate under the action of an external AC power source. Each oscillating circuit has its own natural frequency. When the frequency of the external AC power source is equal to the natural frequency of the loop, the oscillation amplitude (voltage or current) reaches its maximum value. This situation is called resonance. The input circuit of the radio is a resonant circuit. Change the inductance or capacitance of the loop to make the natural frequency of the loop equal to the frequency of the radio station to be received. If resonance occurs, you can choose the signal from this site. The intermediate frequency transformer of the radio is also a resonant circuit. It is tuned at a frequency of 465kHz, allowing the intermediate frequency amplifier to have maximum amplification capability for 465kHz intermediate frequency signals,
In an oscillating circuit with resistors, inductors, capacitors, and an external AC power source in series, resonance occurs when the frequency of the external power source is equal to the natural frequency of the loop. This type of resonance is called series resonance. Series resonance has the following characteristics: the total impedance of the circuit is pure resistance and becomes the minimum value, equal to the circuit resistance; The current in the circuit reaches its maximum value; The voltage on the inductor is equal to the voltage on the capacitor, which is Q times the AC power supply voltage. Therefore, series resonance is also known as voltage resonance.
If the frequency of the external power source is less than or greater than the natural frequency of the loop, the total impedance of the loop will increase and the loop current will decrease. The larger the Q value of the circuit, the steeper the curve, and the more severe the resonance phenomenon.
In an oscillating circuit with inductors, capacitors, and an external AC power source connected in parallel, resonance occurs when the frequency of the external power source is equal to the natural frequency of the circuit. This type of resonance is called parallel resonance. Parallel resonance has the following characteristics: the total impedance is pure resistance and reaches its maximum value; The circuit voltage reaches its maximum value; If the internal resistance of the power supply is large enough to make the total current in the circuit constant, then the current of the two branches is Q times the total current. That is to say, the current direction of the two branches is opposite and the magnitude is similar, and the difference is the total current. So, parallel resonance is also known as current resonance. If the external power frequency is less than or greater than the natural frequency of the loop, the total impedance of the loop will decrease and the voltage of the loop will also decrease. The larger the Q value of the circuit, the steeper the curve, indicating that the resonance phenomenon is more severe.