Constant current power supply usually adopts double-layer winding. The effective part of the coil contains two effective sides on the left and right. The effective edge placed in the slot and close to the slot is called the upper edge, and the effective edge near the bottom of the slot is called the lower edge. The upper and lower layers in the same tank are separated by insulating paper.
The distance between the upper and lower effective edges of the same coil in the circumferential direction is the span of the coil, which is usually expressed as a multiple of the slot pitch (the distance between two adjacent slots). The span is approximately equal to a pole pitch (the distance between two adjacent magnetic poles is also often expressed as a multiple of the slot pitch).
There are 3 types of DC armature windings: stacked winding, wave winding, and frog winding. The two outlet ends of each coil are connected to the two commutator segments of the commutator. The distance between the two on the circumferential surface of the commutator is called the commutator pitch, which is represented by Ys. Different types of windings have different commutator pitches.
For devices that have large changes in the impedance of the load and require the load current to remain basically unchanged, a steady current power supply must be used. The specific technical fields of constant current power supply applications are as follows.
Using steady current power supply, easy arc ignition, and stable arc. Ignition of a small current arc is particularly suitable for welding thin metals in a protective atmosphere. It can also be used in electric arc steelmaking, ore heating furnace, vacuum arc furnace, contact welding, and other equipment.
The electric heating equipment is powered by a steady current power supply, which can save electric energy and improve the power factor. This can achieve better economic benefits for high-power electric heating equipment.
For electric heating and welding equipment, it is better to use AC steady current power supply. In foreign countries, the steady current power supply has been widely used in this kind of equipment.
After the AC steady current is rectified, it can be used for DC power driving. It can be used as a power source for constant torque driving, and it can also be used as a motor starter.
Using steady current power supply to supply power can not only avoid the current impact at the beginning of the start, but also maintain a large starting torque throughout the start process, and will not reduce the motor torque due to the increase in speed and the decrease in current. And always keep the current constant, so that the motor has excellent starting performance. The stabilized current power supply is used to start DC separately excited motors, asynchronous motors, and asynchronous starting of synchronous motors.
Research and analysis show that in a DC separately excited motor if the armature current is kept constant and the magnetic flux is changed accordingly, the motor speed can be adjusted to higher or lower than the rated speed.
Electrical processing equipment. Such as electroplating baths, electrolytic baths, electrochemical processing equipment, etc. The application of a steady current power supply in this equipment can eliminate the influence of anode effect (during aluminum electrolysis), eliminate the influence of tool cathode and product anode short circuit, stabilize the processing process, reduce energy consumption and increase labor productivity.
As a battery charging device. The highest efficiency can be obtained by charging the battery with a steady current power supply. In the industry, most charging devices use steady-current power supplies.
As the power source of the light quantum generator. In the pulsed photon generator, the steady current power supply is used to charge the energy storage capacitor, and in the continuous photon generator, it is used as the power supply of the gas tube. Due to the application of a steady current power supply, the stability and adjustability of generator output are improved. Quantum technology is also one of the most effective fields in the application of a steady current power supply.
In the case of a small power supply capacity and a long transmission line, if the load terminal voltage is required to be stable, the use of a current stabilizing device can eliminate the influence of the change in the voltage drop of the transmission line on the load terminal voltage. This important advantage of the steady current power supply is used for: power supply for airport take-off-landing channel signal lights; power supply system for long-distance and ultra-long-distance cables across continents or oceans.
The highly stable constant current power supply used to detect various pointer instruments can be used to measure precision resistance, use the linear charging voltage of the capacitor to measure the time interval, some sensitive components such as Hall elements, thermal diodes, etc., are working When the sensor performs non-electric conversion of electric quantity, it is necessary to pass a constant current to the sensitive element.