Q:The properties of the single phase magnetic electromotive force of ac motor, the amplitude of its amplitude, the position of amplitude, and the frequency of the pulsations are related to the various factors

When we in the arrangement of the synchronous generator stator winding, always make it a rotating magnetic field generated by the magnetic pole logarithmic p1 logarithmic p is equal to the rotor poles, so under a certain frequency, the rotor speed n is equal to the speed of the stator rotating magnetic field n1, namely they are synchronized; In other words, there is a strict relationship between the speed and the frequency when the logarithm is certain, which is called "synchronization" in motor terms.

Q:Is a single-phase carbon brush motor a dc motor or ac motor?

Phase with a carbon brush motor is dc motor or ac motor, have a plenty of dc motor also have a plenty of ac/dc motor, such as the pistol electric drill majority is ac/dc motors, alternating current (ac) can also be used, direct current (dc) can also be used. (2) (the power supply of the rectifier bridge is not output from the positive and negative terminal.) there must be a positive negative electrode for the power supply of the rectifier bridge, otherwise it is not the power supply of the rectifier bridge. (3) the bidirectional thyristor is applied to alternating current circuit, and if your motor speed is a bidirectional thyristor, it may be alternating current motor. The dc motor carbon brush is the same as the ac motor carbon brush, so the alternating current series excitation machine is used.

Q:Does ac motor use the upper hall sensor

There are temperature sensors that can monitor winding temperature and avoid burning coils; There is a near switch or other sensor switch that can monitor the number of revolutions, or block the protection.

Q:When the ac servo motor is turned off, the rotor shaft is tight

It is necessary to make sure that the servo motor is equipped with the brake device. If there is a brake, the motor will not move when the power is off. If there is no brake, the servo motor should be a free state, and the axis of rotation should be very light, and the axis of rotation can be turned by hand. The load is not well installed, causing the difficulty of turning, releasing the load, turning the motor independently, and confirming the problem by turning the load independently.

Q:What are the advantages of ac generators compared to dc motors? Why is it that today's big generators are talking about generating electricity and getting rid of dc power?

The disadvantages of the single most important one: dc generator, commutator, commutator, to direct current (dc), however, general from the collector ring commutator and carbon brush, mechanical wear, coil and carbon brush to produce graphite powder is easy to pollution, malfunction. Second: industrial dominant, industry important mechanical - three-phase asynchronous motor, the power supply must be alternating current (ac), because an alternating current to produce a rotating magnetic field, the drive motor. Third: alternating current to direct current only needs rectifier bridge, economy, simple. But direct current turns into alternating current costs, and it's complicated

Q:How do ac motors keep moving in the same direction?

Most of the ac motor rotor is not current, power is in the little excitation current of synchronous motor synchronous runtime. Running in the rotor is current, this is in a rotating magnetic field induced current, the rotation of the rotor is also want to rely on the induced current, this is because the wire out of the current is induced in a rotating magnetic field, and wire in the magnetic field force, thus the rotor to turn up, until than the speed of the rotating magnetic field of the lower speed stability, this is the principle of asynchronous motor, so as long as the rotating magnetic field to the same, the motor to the same, how to obtain a rotating magnetic field, a direct current is not, the formation of the three-phase alternating current (ac) is itself a generator stator induced current in the rotor rotating magnetic field, so as long as he is input into the coil on the difference of 120 degrees, can be formed on the stator rotating magnetic field, single phase is somewhat hard to understand, but if you can put the sinusoidal magnetic field is decomposed into two same size changes, in the opposite direction of the synthesis of two rotating magnetic field results, as long as the rotor turns up later, and two the relative speed of the rotating magnetic field induced by the electric current cannot be integrated to zero, still can go up, just start up more troublesome.

Q:How to distinguish dc motor from ac motor?

Ac motor and dc motor two kinds big. (1) ac motor and its control ac motor divided into two categories, asynchronous motor and synchronous motor. The asynchronous motor according to the number of stator phase asynchronous motor is divided into single and two phase asynchronous motor and three-phase asynchronous motor. Three-phase asynchronous motor has simple structure, reliable operation, the advantages of low cost, widely used in industrial and agricultural production. 1. The basic structure of three phase asynchronous motor There are two parts: the structure of the three-phase asynchronous motor stator and rotor. (1) of the stator, the stator is fixed parts, motor function is used to produce a rotating magnetic field. It is mainly composed of stator core, stator windings and the frame. (2) the rotor, the rotor is the key to master the part, there are two kinds of rotor, squirrel cage and wound rotor. Master. Their respective characteristics and difference between cage type used for medium and small power motor (below 100 k), he has simple structure, reliable work, convenient in operation and maintenance. Wound rotor can improve startup performance and adjust the speed, size of air gap between the stator and rotor, will affect the performance of the motor, the general thickness of air gap between 0.2 1.5 mm. Grasp the connection method of stator winding

Q:The electric fan is a dc motor, or the ac motor is good, why?

This depends on whether your power supply is dc or ac, the general household appliance is communication, because the household voltage is not fixed, usually 220V ~ 250V interval

Q:According to the power of motor, how to select the contactor and switch?

Based on the capacity of the three-phase squirrel-cage asynchronous motor, the calculation method for selecting circuit breaker, contactor, heat component and conductor is as follows: 1, the capacity of the motor is set to X (kW), the rated current of the motor as: 2 * X (A), in general, with the motor nameplate rated current of the difference is very small, if not sure, can take the motor manual check. For example: motor power 7.5 (kW), rated at 15 (A); The motor power 55 (kW), the rated current is 110 (A).

Q:Can alternator speed improve power generation?

The first thing to verify is the synchronous generator, or the asynchronous generator. This synchronous generator, at synchronous speed (1 pair, 3000 RPM, 50Hz) In this case, the asynchronous generator is operating at a lower speed than the synchronous speed. The speed above synchronous speed is in the operating condition of generator