JPS60249893A - Secondary chopper controller for wound-rotor type induction motor - Google Patents

Abstract

PURPOSE:To set the secondary loss of an induction motor substantially to zero at operating time by connecting a diode and a capacitor in parallel with the secondary current control chopper, and connecting a starting resistor in parallel with the capacitor at the starting time to regenerate power after the starting is completed. CONSTITUTION:A rectifier SR is connected with the secondary winding of a wound-rotor type induction motor M, the DC output side of a rectifier is intermittently shortcircuited by a chopper circuit GTO to control the secondary current. A circuit which has a diode D and a capacitor C connected in series is connected in parallel with the chopper GTO, a starting resistor R is connected in parallel with the capacitor C at the starting time, and the resistor R is disconnected from the capacitor C after the starting is completed. Thus, power charged in the capacitor C is regenerated to an AC power source through a filter having a reactor L and an auxiliary capacitor CA and an inverter GIV to reduce the secondary loss, thereby operating in high efficiency.

Description

[Detailed Description of the Invention] [Technical Layers of the Invention] The present invention provides short-circuiting intermittently by a chopper inserted in the secondary circuit of a wound type conductive motor.
This invention relates to a secondary chopper control device for an induction motor that controls f.

[Technical background of the invention and its problems] The induction motor secondary chopper control device ML obtains the same effect as secondary resistance variable control in an isometric manner by intermittently shorting the secondary resistance. However, there is a problem that the secondary loss is almost the same as that of variable secondary resistance control, and the operation efficiency is low.

[Object of the Invention] The present invention improves the efficiency of operation by reducing the secondary loss, which is a problem with the conventional system Of, compared to the case of secondary variable resistance control, and improves the efficiency of operation. The objective is to obtain a secondary chopper control device.

[Summary of the Invention] In order to achieve the above object of the present invention, a straightener is connected to the secondary winding of a spring linear induction machine, and the direct current output side of the limb straightener is intermittently connected to a chopper circuit. In a device that controls the secondary current by shorting the circuit, a circuit in which a diode and a capacitor are connected in series is connected in parallel to the chopper circuit, and a starting resistor is connected in parallel to the capacitor during startup. The starting resistor is separated from the capacitor, and the power charged in the capacitor is regenerated into an AC power supply by an inverter device via a filter consisting of a reactor and an auxiliary capacitor. Wound induction electric wire that enables efficient operation#
This is a secondary chopper control device for one machine.

[Embodiments of the invention]
This will be explained with reference to an example shown in the figure.

A rectifier is connected to a direct current section in which the secondary of the piezoelectric motor M is rectified by a rectifier SR, a surge absorber consisting of a capacitor C is connected, a secondary resistor R is connected in parallel to C via a switching contactor CTT, and an OTO element. OTo constitutes a part of the chopper, and 2 and 1Ltj are intermittently short-circuited to the dissipation section.

The secondary resistor R is used only for starting, and when the controller accelerates at a constant speed, the contactor CT disconnects R, and the energy stored in the capacitor is rectified with the GTO element through a filter circuit consisting of a reactor L and an auxiliary capacitor LA. 0, that is, the chopper off 4th whistle, which is switched to return to the power supply side at I/Tooker G V, which combines the elements.
It diverts the current and temporarily stores the energy of the motor's leakage inductance in the capacitor. A starting resistor R is connected to the capacitor, and a switching contactor CT is connected after starting is completed.
Switch to filter reactor L at T.

Main capacitor 〇 Tori Akudor L and auxiliary capacitor L
A filter circuit is constructed, and the energy accumulated in the capacitor is smoothed and transmitted to the GTO inverter GIV for inverse conversion. GIV works by returning the energy of the capacitor to the commercial power source using an inverter made up of GTo and rectifying elements.

The control circuit first generates a speed reference in the speed control circuit RF and inputs it to the speed control circuit NC. Furthermore, the speed is detected by a speed detector TO directly connected to the main motor Mi and inputted to the NC as speed feedback. The output of the NC is input to the current control circuit CC as a current reference. Further, a current detector SH inserted into the main circuit detects the current and inputs it to CC as current feedback. The output of the CC is given as the conduction rate,
Input to conduction rate control circuit #JP1-IC. Turn on and off GTO according to PHCd conductivity criteria. A speed signal is received from the contactor control circuit CTC/NC, the completion of acceleration is detected, and the connection of one terminal of the capacitor is switched from the R side to the L side at C'If'T. The inverter one-firing control circuit PHIi is connected to the inverter synchronization signal circuit SS (in response to FJ, the GIVO firing angle -?J+4 control (for example, β-0°)
What do you mean?

If the reverse voltage on the DC side of GIV is set higher than the DC voltage equivalent to the motor secondary voltage at the lowest speed in the speed control range using the above circuit, the leakage inductance energy (4) of the motor can be It can be a circuit that recovers it to the source side.

Since GIV uses GTO and is a self-extinguishing element, it is possible to control β-00, which allows the power factor of inverter GIV to be close to 1.
= can be of the form that deals only with the effective current component.

[Other Embodiments of the Invention] If the firing phase of the inverter GIV is made variable, it is possible to perform constant voltage control or variable voltage control of the capacitor voltage, but in this case, the reactive power of the inverter increases.

As shown in FIG. 2, the motor side or the inverter side can be multiplexed, thereby reducing the harmonic current flowing to the fabric edge side.

Further, even if the inverse converter is converted into PWM and controlled, it is possible to prevent an increase in the reactive power of the fundamental wave.

In addition, a power ID inverter device that allows a slight reduction in power factor can be configured with a thyristor element to achieve natural commutation.

[Effects of the Invention] The present invention enables highly efficient operation by reducing the secondary contact loss of the driving shaft to zero, and makes it possible to reduce the power factor of regenerative operation by the inverter to 1. Become.

For applications such as chopping and square torque loads, it is possible to provide an economical secondary chopper control system using winding configurations by reducing the size of the inverter device relative to the machine capacity. .

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of one embodiment of the present invention, and FIG. 2 is a configuration diagram of a joint embodiment of the present invention in which the present invention is multiplexed. M... Motivated by winding form i+ SR... Urgent, instrument CI
T O...+t'i'o Chojijikuichi circuit D...
Rectifying element (diode) C...Capacitor I...Resistor TO...Speed detector S) I...Current detector
CTT...Felling machine CA...Auxiliary capacitor L...
Reactor GIV... o 'i' o Inverter device agent Patent attorney Nori Chika Teruyuki (and 1 other person) Figure 1 SRGzv SH' atv

Claims (2)

[Claims] (1) Winding configuration In a device in which a rectifier is connected to the secondary winding of a conductive motor and the DC output side of the rectifier is intermittently short-circuited by a chopper circuit to control the secondary current, a diode and a capacitor are used. A series-connected circuit is connected in parallel to the chopper circuit, a starting resistor is connected in parallel to the capacitor at startup, and after startup is completed, the starting resistor is disconnected from the capacitor, and the power photoelectronized to the capacitor is transferred to a reactor. A secondary chopper control device for a winding motor and conductive motor, characterized in that the AC power is regenerated by an inverter device through a filter consisting of an auxiliary capacitor. (2) The front h-bi inverter device is an inverter device using self-extinguishing elements, and the firing phase angle is constant (for example, β = 0).
6. A secondary chopper control device for a wound type induction electric machine as claimed in claim 1.