JPH0287972A - Chopper type dc power source equipment - Google Patents

Abstract

PURPOSE:To suppress surge current by connecting a surge current limiting resistor in parallel with a thyristor and providing a gate signal from an inductor to the thyristor. CONSTITUTION:A surge current limiting resistor 24 is connected in parallel with a thyristor 12, i.e., a triac, the gate signal therefor is provided from the coil of an inductor 17 through a diode 25 and a resistor 26. By such arrangement, surge current can be suppressed sufficiently, and self starting can be realized by providing the gate signal from the inductor 17.

Description

DETAILED DESCRIPTION OF THE INVENTION (Object of the Invention) (Industrial Application Field) The present invention relates to a chopper type DC power supply device equipped with an inrush current prevention mechanism.

(Prior Art) As a DC power supply device (DC lighting device) used for lighting control of a lamp, one having an inverter transformer is used, and a starting signal (gate signal) for a forward conversion thyristor device is sent to the inverter transformer. It was supplied from However, recently, chopper-type DC power supplies have come into use as this type of DC power supply. In the case of this chopper type, since it does not have an inverter transformer unlike the conventional type, it is not possible to supply the 1111 signal to the thyristor device.

Further, in this type of DC power supply device, a large inrush current flows at the time of startup, causing stress on semiconductor elements and adversely affecting peripheral equipment, and it is necessary to suppress this inrush current.

(Problems to be Solved by the Invention) In other words, the chopper type DC power supply device requires a special circuit for supplying a gate signal to the thyristor device, and also requires measures against inrush current.

An object of the present invention is to provide a chopper type DC power supply device that can supply a gate signal to a thyristor device without requiring a special circuit, but has an effective suppressing function against rush current. [Structure] (Means for Solving the Problems) A chopper-type direct IS source device according to the present invention includes a conversion section that has a thyristor device and converts AC power into predetermined DC power, and a DC output side electrical circuit of this conversion section. It is equipped with a chopper and a smoothing inductor. Further, a resistor for inrush current limiting is connected in parallel to the thyristor device, and a gate signal to the thyristor device is supplied from the inductor.

(Function) In the present invention, since the thyristor device is in the OFF state, the inrush current at the time of starting flows through the inrush current limiting resistor connected in parallel with the thyristor device. Therefore, the value is sufficiently limited by the resistor, and will not damage the semiconductor element or adversely affect peripheral equipment. The chopper operates according to the value limited by this resistor, and when current flows to the load through the smoothing inductor, a gate signal is supplied from the inductor to the thyristor device, and the thyristor device is turned on. Therefore, the current flowing through the resistor flows through the thyristor device, automatically transitioning to normal operating conditions. That is, there is no need to provide a special circuit for activating the thyristor.

(Example) An embodiment of the present invention will be described with reference to the drawings.

In the figure, reference numeral 11 denotes a conversion section which has a thyristor device 12 and converts AC power generated from a commercial AC power supply 13 to output a predetermined DC power from the DC side of a full-wave rectifier 14. As the thyristor device 12, for example, a bidirectional triac is used, and the full-wave rectifier 1
It is provided in the AC side circuit of No. 4.

The AC output @ electric path of the converter 11, that is, the DC side electric path of the full-wave rectifier 14, is provided with a chopper transistor 16 between the collector and emitter and a smoothing inductor 17 in series, and the load is transmitted through these. It is connected in series with a certain lamp 18.

A capacitor 19 is connected to the collector side of the transistor 16 of this DC side circuit between the (+) pole side circuit and the ←) pole side circuit. Further, on the emitter side of the transistor, a diode 20 is provided, the cathode being connected to the (+) pole side electric path, and the anode connected to the ←) pole side electric path. Further, a capacitor 21 is connected in parallel between both ends of the lamp 18.

23, a control circuit inputs signals from the (+) terminal of the full-wave rectifier 1514, which is the input side of the chopper transistor 16, and the illustrated upper terminal of the lamp 18, which is the output side of the transistor 16; A signal is output to the base of the chopper transistor 16 to turn it on and off at a predetermined period.

Here, an inrush current limiting resistor 24 is connected in parallel to the tri-hook, which is the thyristor device 12. Further, the gate circuit of the triac 12 is connected to the coil of the inductor 17 via a diode 25 and a resistor 26, and a capacitor 27 is connected between the lines of this gate circuit.

With this configuration, the triac 12 connects the inductor 1
The gate signal supplied from 7 is controlled to be conductive at a predetermined phase.

In the above configuration, when the voltage of the power supply 13 is turned on, a rush current tends to flow through the capacitor 19 and the chopper transistor 16 to which the first ON command is applied from the control circuit 23, respectively. However, at this time, the triac 12 is still in an inactive state, and current flows through the inrush current limiting resistor 24 to the subsequent circuit. In other words, the inrush current at the time of start-up, as described above, has a value that is sufficiently limited by the resistor 24. Therefore, no stress is applied to each semiconductor element, and adverse effects on peripheral equipment can be prevented.

When the limited current flows through the chopper transistor 16 and the smoothing inductor 17 to the lamp 18, a voltage is induced in the coil of the inductor 17.
This becomes a gate signal to the triac 12 and activates the triac 12. When the triac 12 is activated, the current flowing through the resistor 24 flows through the triac 12, and the normal operating state is resumed.

In this way, when the power supply voltage is turned on, a current flows through the resistor 24, and thereafter the triac 12 is activated by the voltage induced in the coil of the smoothing inductor 17, and the triac 12 is automatically shifted to the normal operating state. can. Therefore, an excessive rush current will not flow when the power supply voltage is turned on, and will not stress the semiconductor elements or adversely affect peripheral devices. Further, since the voltage induced in the smoothing inductor 17 is used as a gate signal to start the triac 12, there is no need to provide a special circuit for starting the triac 12. Furthermore, since the current path is automatically switched from the resistor 24 to the triac 12, lightning callos do not occur during operation, regardless of the turn.

In the above embodiment, the thyristor device 12 includes 1 to 1.
Although a LIAC is shown as an example, other elements such as an SCR may be used.

〔Effect of the invention〕

As described above, according to the present invention, the power source? J at the time of H pressure pitcher
The inrush current of 3 can be limited to a sufficiently small value, and this is done by supplying the goo signal from the smoothing inductor to the thyristor Rffl to automatically start it, so there is no need to provide a special circuit for starting the thyristor device. be.

[Brief explanation of the drawing]

The figure is a circuit diagram showing an embodiment of a chopper type DC power supply device according to the present invention. 11... Conversion section, 12... Thyristor device, 13... AC power, 16... Chopper transistor, 17... Inductor, 18... Load, 24... Inrush current limiting resistor.

Claims (1)

[Claims] (1) A converter having a thyristor device and converting alternating current power into predetermined direct current power, and a chopper and a smoothing inductor provided in the DC output side circuit of the converter, and an inrush current flowing into the thyristor device. A chopper type DC power supply device characterized in that a limiting resistor is connected in parallel and a gate signal to the thyristor device is supplied from the inductor.