RU2145767C1 - Device for automatic regulation of voltage of induction generator - Google Patents

Abstract

FIELD: electrical engineering, in particular, induction generators for field environment operations. SUBSTANCE: goal of invention is achieved by connection of electric motor load which is comparable to power of induction generator. Device has induction generator, which is driven by internal combustion engine. Stator of induction generator is connected to assembly of direct capacitors, assembly of switching capacitors, and group of starting capacitors. Three-phase electronic gate is connected in parallel to starting capacitors. Zero point of assembly of switching capacitors is connected to pulse-width control circuit, which input is connected to output of measuring transformer. One terminal of control unit is connected to phase lines of generator; another terminal of control unit is connected to control electrodes of triacs. EFFECT: increased reliability. 1 dwg

Description

 The proposed device relates to electrical engineering and can be used to control the voltage of autonomous asynchronous generators used in the field.

 With an obvious advantage (simplicity of design, reliability, etc.), asynchronous generators (AG) have a significant disadvantage, namely, that without additional devices that stabilize the voltage, they cannot supply the motor load, and when the motor load is connected, it is comparable with power generator, the latter lose their excitement. Therefore, to control the voltage of the AG additional devices are needed.

 Known devices for regulating the voltage of the AG, which in the General case contain a group of capacitors and a capacitive power controller, made in the form of various adjustable inductances, for example, see A. with. USSR N 113315, N 188550, N 312360, N 509970, etc. Various electronic devices can be used as regulating elements, for example, see A. with. USSR N 443443, 760382, 688977, etc.

 All these devices have a significant drawback when connecting a motor load commensurate with the power generator, the generator loses excitation.

 A device is known for regulating the voltage of an asynchronous generator, see.with. USSR N 477512, class H 02 P 9/46, taken by the authors as a prototype and containing a battery of non-switched capacitors connected to 3 phases of the generator, a battery of switched capacitors and a measuring transformer, the output of which includes a pulse-width control circuit for key elements.

 The disadvantage of this device is that when you connect a motor load commensurate with the power of the generator, the latter loses excitement.

 The technical solution of the invention is to eliminate this drawback, namely the creation of the possibility of connecting a motor load, commensurate with the power of the asynchronous generator.

 This object is achieved in that the device for automatically controlling the voltage of the asynchronous generator, comprising a battery of non-switched capacitors connected to the phases of the generator, a battery of switched capacitors and a measuring transformer, the output of which includes a pulse-width control circuit, additionally contains a control unit and a three-phase switch, for example triac, shunted by a group of starting capacitors, and the control unit on one side is connected to the phases of the generator, and with ugoy hand - to the triac gate and the output of the measuring transformer.

 The invention is illustrated in the drawing, which shows an electrical diagram of a device for automatic voltage regulation.

 The device contains an asynchronous generator 1, driven by an internal combustion engine 2. A non-commutated capacitor bank 3, a switched capacitor bank 4 and a group of starting capacitors 5 are connected to the stator of the asynchronous generator 1. A three-phase electronic switch 6 is connected in parallel with the starting capacitors 5. At the zero point of the switched battery capacitors 4 includes a pulse-width-pulse control circuit 7, the input of which is connected to the output of the measuring transformer 8, the control unit 9 on one side It is connected with the phases of generator 1, and on the other hand, with control electrodes of triac 6.

 A device for automatically controlling the voltage of an asynchronous generator operates as follows. After starting the drive motor 2, the asynchronous generator is self-excited from the battery of non-switched capacitors 3. The voltage of the asynchronous generator 1 is supplied to the control unit 9. The control unit sends a signal to turn on the three-phase electronic switch 6. The latter is turned on and supplies voltage to the load A, B, C. At idle during operation of the generator, the battery of switched capacitors 4 is disconnected. When the load is connected, the voltage on the generator 1 decreases and the pulse-width-pulse control circuit 7 changes the current, which, in proportion to the voltage decrease, increases the capacitive current of the battery of switched capacitors 4, thereby restoring the voltage on the asynchronous generator 1. When connecting a motor load, commensurate with the power of the generator 1, the current in the circuit increases, the voltage of the generator 1 decreases, because the battery capacity of the switched capacitors 4 is not enough to compensate for the reactive component of the load. The signal from the current transformer 8 increases and the control unit disconnects the electronic switch 6, and the load is turned on in series with the starting capacitors 5. The latter compensate the inductive component of the starting current and restore the voltage at the terminals of the generator 1. After starting a motor load of comparable power, the current in the load circuit decreases , this leads to the fact that the control unit sends a signal to turn on the three-phase electronic switch, which turns on and shunts the group of starting con ensatorov. Further power supply of the load occurs through the electronic switch 6, and the voltage regulation is carried out by the pulse-width control circuit 7.

 The use of this device for automatic regulation of the voltage of an asynchronous generator allows in a standalone power source of small power to start engines of unit power equal to the power of the generator. This is especially important in the field. For example, a 4 kW power plant with a network voltage of 220/127 V and a current frequency of 200 Hz can power any electrified tool used to repair railway tracks (drills, grinders, crutches, rail cutters, vibrators, wrenches, etc., with a unit power of 0 , 6 to 4 kW).

Claims (1)

 A device for automatically controlling the voltage of an asynchronous generator, containing a battery of non-switched capacitors connected to the phases of the generator, a battery of switched capacitors and a measuring transformer, the output of which includes a pulse-width control circuit, characterized in that it additionally contains a control unit and a three-phase switch, for example, a triac shunted by a group of starting capacitors, and the control unit is on the one hand connected to the phases of the generator, and on the other hand, to ulation triacs and output electrodes of the measuring transformer.