DE247992C - - Google Patents

Description

IMPERIAL

PATENT OFFICE.

^! ^ PATENT LETTERING

HPl ^ ΤΙΛ Λ / ΓΤΑΑΛ

- JV * 247992 CLASS 21 d. GROUP

in DUISBURG.

Patented in the German Empire on October 16, 1910.

The important task for metallurgical plants and conveyor systems, for three-phase drives to bring about economical route regulation in connection with phase improvement, cannot be solved by using them as a Collector motors are run. Therefore coupled collector auxiliary machines are used, used as a motor or generator in the

ίο The slip circuit is working. Get this however, the dimensions are too unfavorable for main engines with a low number of revolutions. One also has Collector motors lying in the slip circle coupled with asynchronous machines, so that through this energy is transferred to the network or absorbed in the case of synchronous tours will. In order to reduce the number of machines, one has collector and induction machines combined to · period converters, similar to those that were previously used exclusively has proposed to phase improvement. Since such period converters have their own torque on all tours to the Motor run relatively synchronously, can have a mechanical connection with the latter or a Auxiliary synchronous motor or double field motor for the drive can be dispensed with. According to the previous ones The stator of the period converter is always in direct contact with proposals with the working circuit, and the degree of compensation of the whole system is of the Brush position dependent.

The stator of the converter can, however, be regarded as a secondary motor component, which initially only needs to carry electricity to overcome the friction effect; and one often becomes a simple regulating circuit can apply according to the present invention, in which the stator only inductively with is chained to the rotor. Apart from the special ones followed in the description direct advantages result 'thus also the possibility of any inductive Phase regulation to improve the power factor. You can also use the common collector motor arrangements the phase for the various operating states readjust, namely z. B. by brush displacement, however, is such to avoid expediently with regard to auxiliary commutation fields. The at mechanically relative synchronized machines possible other mechanical rotations to achieve the Phase compensation prove to be too cumbersome, and the sometimes used phase sending transformers or auxiliary phases and phase combinations are in the converter stator, if a phase adjustment is to take place, for reasons of simplicity also not in place. The arrangement of the present invention allows within practical limits of regulation the independently controllable compensation through simple resistance regulation, which is all the more important as it is in many

Claims (2)

drove, ζ. B. for compressors with step operation, it is not uncommon for one and the same converter to alternate with different Motors of different compensation claims has to work. The device is as follows: The slip currents of the induction motor H are fed to the collector of the period converter P. From there you go through a transformer T ίο into the network. Other, usually less favorable, variations are also possible, e.g. B. the transformer can also be between the induction motor H and P period converter. An auxiliary winding W , which is short-circuited via an adjustable resistor R, is attached to the stator of the converter in order to achieve an independent speed of the converter, the necessary synchronizing force and a controllable compensation. You can now get the main and auxiliary machines running from the mains and, by regulating the resistors A and R and the transformer T, enable an interconnection at L with the correct voltage and number of periods, so that A can be switched off. The slip circuit L, which is connected to the collector K , has the same number of periods as the stator circuit W of the period converter, and the existing synchronizing force proves to be sufficient with a suitable construction of the converter to ensure the relatively synchronous operation between motor and period converter under all practical Maintain operating relationships. The number of revolutions of the converter is of course determined by the number of periods of the network N and the number of revolutions of the induction motor H. If you think z. B. induction motor and period converter with the same number of poles, the period converter will have the same number of revolutions as the induction motor. However, by switching the phases, it is also possible to have the motor run over-synchronously in relation to the number of mains periods and the period converter accordingly run under-synchronously, and you can achieve the correct speed in any case by regulating from synchronism. The converter voltage has an additional effect when the motor is over-synchronized on the rotor. The adjustment of the relatively synchronous number of revolutions of the system and the change is done by adjusting the regulating transformer, where increasing the voltage decreasing or increase in engine tours results. If both machines run relatively synchronously, a regulation at R essentially only results in a change in the wattless currents, and it can therefore be used advantageously for compensation regulation in order to adapt to the different operating states or to the cooperation with different main machines. A reduction in the resistance W results in an increase in the current between the motor and converter in a certain area while reducing the total current for the machine set. Even if the resistance W increases, the current in the slip circuit will eventually increase. As a result of its phase position, however, the total current also increases, so that the power factor deteriorates. There is a certain similarity of this behavior with that of an ordinary synchronous motor, and the phase improvement can take place within wide limits even in the case of large main machines without the stability of the gear being endangered. The small loss in the regulating resistance is all the more negligible since only very little resistance is switched on for a practically large regulating range. Since the relatively synchronous tours of the system as well as the tour differences between idle and full load are somewhat dependent on the wattless currents, you can readjust the tours and the mentioned tour differences by readjusting at R, which changes the wattless currents. The power factor is deteriorated somewhat as a result, and this regulation is therefore only possible for fine levels. A particular advantage of the arrangement is that the converter stator is once and for all given an unchangeable winding for a voltage that appears to be suitable. In addition to the resulting advantages in production and the possibility of taking all operating modes into account in the simplest possible way simply by regulating the transformer T and regulating resistors and R , there is also an advantage that the winding W in the depending on the circuit in the case of careless regulation, possible inadmissible tensions are not directly affected. With single-phase network you can z. B. Help phases of known effect. while the three-phase slip circuit is expediently retained. Godfather ν t-An Proverbs: i. Arrangement for regulating the speed and the compensation of Induction motors by period converters, characterized in that the period converter on the stator has an inductive, has resistance regulated circuit, such that through this and Transformer regulation Tour change, through the resistance regulation but only an improvement in the power factor is achieved. 2. Procedure for finer route regulation and regulation of route waste when loading the arrangement according to i, characterized in that with the aid of the Resistance regulation of the inductive stator circuit of the period converter the degree of compensation effecting the changes mentioned is changed. For this purpose ι sheet of drawings.