How to limit the current of alternating current, what equipment or method to use 30

Analysis: Because the current is limited for alternating current, it is enough to control the impedance in the circuit.

Suggestion: If the inductive reactance is used for control, a coil can be connected in series in the circuit (there are multiple taps to facilitate changing the inductive reactance value).

If the capacitive reactance is controlled, a capacitor can be connected in series in the circuit (multiple capacitors can be connected in series or parallel to easily change the total capacitive reactance).

The above two methods are relatively simple and feasible.

Of course, the method of connecting a resistor in series can also be controlled, but it will consume additional electrical energy, which is not advisable).

Alternating current. Current limiting, either with an inductor coil or in parallel.

method. The inductance coil has impedance, and the role of the ballast of the fluorescent lamp is to generate instantaneous high voltage when it is started, and when the fluorescent lamp is working normally, it plays the role of voltage stabilization and current limiting.

The voltages in the parallel circuit are equal, and the total current is equal to the sum of the currents of the branches. Parallel circuits can be used to shunt currents.

Assuming you are 220V, assuming that you are really a hundred ampere level of current, the power will be tens of kilowatts.

If you want automatic control, you must have a current detection circuit, and you must also have an actuator.

If you want precise control, you can use a large thyristor for the actuator;

If it is only rough, the actuator can be used with a transformer with multiple taps and an AC contactor.

A sliding rheostat can be connected in parallel to limit the current, and a sliding rheostat can be divided in series

With the same voltage, the power and current of the circuit are determined by the load and no equipment is required.

The current is changed by connecting thyristors in series in the circuit to change the conduction angle.

Shunt resistor shunt, which is also equivalent to reducing the port load voltage.

1. First of all, under the condition of no load on the boot, adjust the voltage knob to the voltage value you want, not only look at the meter, it is best to use a multimeter to measure it, the meter head of this low-grade power supply is often inaccurate;

2. Tighten the current knob to the minimum in the shutdown state, and use the wire to short the positive and negative poles of the power output terminal, if possible, it is best to put the multimeter between the positive and negative poles of the ridge of the electric soft output terminal through the current gear string;

3. When the machine is turned on, because of the short circuit of the output, the current meter head (preferably on the multimeter) shows the current after the current limit, and the current displayed by the voltmeter head is the voltage established by the on-resistance. Adjust the current knob so that the meter current is the current limiting current you need;

4. Shut down, remove the short-circuit wire, and connect your load; When the machine is turned on, it is the working mode of voltage regulation and current limiting. That is, when the load resistance value is large enough, the power supply is in CV (constant voltage) mode, and the current is less than the current limiting current Wangji seepage; When the load resistance value is relatively small, the current will enter the CC (constant current) mode after reaching the current limiting current, and the voltage drop is less than the stable voltage you originally set, because according to Ou Feng Cong's theorem, voltage = current x resistance, because the resistance is small, and the current is limited, the voltage can not be maintained at a stable voltage.

As shown in the figure, when the current in the circuit is too large due to short circuit or excessive power of the connected electrical appliances, the magnetism of the electromagnet becomes stronger, and the force that attracts the armature becomes larger, so that the armature turns to the left, and the gate knife switch automatically opens under the action of the spring, cuts off the circuit, and plays an insurance role

So the answer is the family ridge: current; become stronger; become larger; Springs