Hva er funksjonene og egenskapene til enfase AC universalmotor?
1. Funksjoner av enfase AC universalmotorer
Fordeler:
1) kan brukes for både AC og DC;
2) Høy hastighet, vanligvis 400035000 RPM/Min;
3) Praktisk hastighetsregulering (spennings- og hastighetsregulering), og hastigheten har ingenting å gjøre med strømfrekvensen;
4) Startmomentet er stort, 47 ganger det nominelle dreiemomentet;
5) De mekaniske egenskapene er myke, og overbelastningskapasiteten er sterk;
6) Effektiviteten er vanligvis 30 prosent 70 prosent;
7) Liten størrelse og lett vekt;
Ulemper:
kullbørster og kommutatorslitasje, reverseringsgnister, elektromagnetisk interferens, etc.
2.For 1-fase AC-seriemotor har den 4 egenskaper under stabil spenning og frekvens
1)The relationship between current and torque: I=f(T), which is similar to a parabolic characteristic. If don't consider the influence of magnetic circuit saturation, T∝I2;
2)The relationship between current and speed: I=f(n), which is similar to a hyperbolic characteristic. When the power supply voltage is constant and the effect of magnetic circuit saturation is not considered, n∝(1/I);
3)Forholdet mellom hastighet og dreiemoment: n=f(T). Denne karakteristiske kurven er en myk karakteristikk;
4)The relationship between power factor and torque: COS(ф)=f(T), it is a straight line close to the level. The power factor of this type of motor is high, above 0.9, and the high-speed motor can be above 0.95;
In addition, the no-load speed of a single-phase series motor is theoretically infinite, so the no-load speed is very high. Therefore, the mechanical strength of the motor is usually taken into consideration, and no-load operation is not allowed for fear of "speeding." But in fact, due to the friction of the bearing, the pressure and friction of the brush, the wind friction of the armature and the demand for ventilation and heat dissipation, the armature is equipped with fan blades, which is equivalent to adding a small load to the motor, so the actual no-load speed is not It may be infinite. But the no-load speed is still relatively high, generally 1.5 to 3 times the rated speed, or even higher.
