SU304889A1 - Synchronized brushless DC motor - Google Patents

Description

Brushless DC electric motors are known, made in the form of a siichroin machine connected to a power source via a switch on thyristors controlled by a rotor position sensor powered by a voltage converter with pulses with a synchronization frequency.

The proposed electric motor is characterized in that it is in series with a power source including a booster device combined with a secondary winding of a converter transformer.

This eliminates all bulky auxiliary devices for closing thyristors, starting at zero frequency at the time of starting the engine.

Pa figs. 1 shows a schematic diagram of an electric motor; in fig. 2 - its mechanical characteristic.

An electric motor with four phases 1–4 and one pair of poles has a transformer rotor position sensor 5 with the corresponding number of phases 6–9 and a pair of poles. It feeds the motor with a direct current source 10 through a voltage boosting device, made on the secondary winding 11 of the transformer 12 of the converter 13. The latter can be made according to any of the known schemes.

which are short and short pulses from the secondary wrap of the rotor position sensor, and are locked 5 with the help of an add-on device.

When applying the voltage of a pigapi; The driver 13 is energized.

Let the secondary winding of the transformer 12 be, for example, Lsenis with the polarity shown in the drawing. The frequency of the transform in this case is selected by the phplpme

...;, g ,.

where / pr - frequency converter; and -speed, which must be locked; 111 - the number of phases of the engines; 2 // - the number of Iar poles.

If the rotor of the sensor is located in the floor (geetias. Shown in Fig. 1, then positive; the pulse of phase 6 of the sensor is supplied to the following: ip1 lupdium electrode of the thyristor 14. The next will be opened during this period of converter operation, since the fusion with ; ooGg -: otki and turned on and hangouts) the same -: iy pygan; 1; h and pa electrolytes "anode-cathode rHjVuCTOpr. M- the resultant K11 is valid, its input f-- - (

t-lTllT).

the rotor is in the same condition. And since its total and already direct voltage acts on the electrodes, i.e. Urc + pete, it opens, and a current flows through phase 1 of the motor, creating a torque.

When the rotor is rotated 90 ° clockwise, a positive pulse from phase 7 is fed to the control electrode of the thyristor 16 already, and with the polarity of the voltage boost indicated in FIG. 1, a turn-off switch 16. The current flows through the phase, creating a torque, etc. The rotor is accelerated and when the speed reaches a value at which the frequency of supplying the control pulses to each control electrode of the thyristors becomes equal to / right, the speed will be set and will be determined only by the frequency of the converter. In this case, a current pulse will flow through each phase, the duration of which is determined by the pulse duration of the converter.

To control the speed of such an electric motor, it is sufficient to change the frequency of the converter.

The electric motor can be widely used in automation systems, computing

telemechanics, i.e., where, in addition to speed synchronization, the actuator requires a certain number of pulses.

In addition, the use of boosting with the purpose of controlling thyristors allows an increase in the power of the electric motor with semiconductor switches on the thyristors.

Claims (1)

Invention Formula A synchronized brushless DC motor containing a synchronous machine connected to a power source through a switch on the thyristors controlled by a rotor position sensor powered by a voltage converter with pulses of a synchronization frequency, characterized in that, in order to simplify the circuit and improve reliability, sequentially with the power source, a booster unit is included, combined with the secondary winding of the transformer included in the specified converter. Rig.2