JPH0445046Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a power supply voltage fluctuation generating device for testing the dip phenomenon caused by the power supply voltage of electronic equipment.

[Prior art]

In general, electronic devices that receive power from a power source often lose normal operation due to fluctuations in the power source voltage for some reason. This phenomenon is called a power supply voltage dip phenomenon. Needless to say, it is desirable to prevent such abnormalities in electronic equipment.
To this end, generating a simulated dip phenomenon in advance and testing how much dip the device can withstand will be of great help in preventing abnormalities. For this reason, a power supply voltage fluctuation generating device (hereinafter referred to as a dip generating device) has become necessary.

Conventional dip generators of this kind have two methods, as shown in the circuit diagram of Fig. 2, in which a variable resistor 1 is inserted in series with a load 2 to change the resistance value and change the output voltage, and as shown in Fig. 3. As shown in the circuit diagram, there was a method in which the output voltage was changed by changing the tap of the secondary winding of the transformer 5 under the control of the triaxes 6-1 to 6-4. However, the former method has the disadvantage that distortion occurs in the dip voltage when the load becomes nonlinear, and the latter method uses a transformer, making it bulky, heavy, and expensive, especially for large current applications. There was a drawback.

[Purpose of invention]

The purpose of this invention is to suppress the heat generation of the transistor by controlling the output voltage using a transistor and controlling the thyristor to supply the output when the output voltage is normal, in order to eliminate the above-mentioned drawbacks of the conventional technology. The object of the present invention is to provide a dip generating device which is small in size and can improve economical efficiency.

[Structure of the idea]

The power supply voltage generator according to the present invention is constructed by connecting the emitters of a PNP transistor and an NPN transistor in common, and connecting the collectors of each via two diodes connected in series in the same direction. Regardless of whether AC or DC dip voltage is applied between the base,
a voltage control circuit that generates a voltage using the dip voltage as a reference voltage between a connection point of the two diodes and a common connection point of the emitters; A bypass circuit consisting of two thyristors connected in parallel and with opposite polarity to each other and turned on/off in response to a control voltage is provided between the series connection points, and the voltage control circuit and the bypass circuit are connected in parallel. The connection point is connected in series between the DC or AC input power source and the load, and
By receiving the input power supply voltage and selectively using a voltage divider circuit if the input power supply is DC or a transformer if it is AC, a selected DC or AC voltage proportional to the input power supply voltage is generated as the dip voltage. When a normal voltage is supplied as the control voltage, the two thyristors of the bypass circuit are turned ON, and at other times,
The present invention is characterized by providing a control circuit having a voltage circuit that generates a control voltage to turn off.

[Example of idea]

Next, embodiments of the dip generating device according to the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing a circuit configuration of an embodiment according to the present invention. In this figure, 11 is a power supply,
The voltage generated may be alternating current or direct current. 12,1
3 is a control transistor, and 14 and 15 are diodes, which are used to prevent transistors that should be turned off from being bypassed and turned on when the voltage of the power supply 11 is alternating current.

Reference numeral 16 denotes a control circuit, which includes a circuit for detecting the power supply voltage applied between terminals 19 and 20 and freely setting a dip voltage, thereby providing a control signal to transistors 12 and 13. It is. 17 and 18 are thyristors, and 23 is a load.

In the above configuration, let us now consider a case where thyristors 17 and 18 are not inserted, and assume that a voltage e _io is applied between terminals 19 and 20. If the control circuit 16 detects this voltage and applies the dip voltage e _d to the transistors 12 and 13, the transistor circuit will detect the dip voltage e _d
It works as a constant voltage circuit with the reference voltage as the reference voltage. As a result, the output voltage e _put appearing between terminals 21 and 22 becomes e _put = e _d −V _be . In this equation, V _be represents the voltage between the base and emitter of the transistor, typically 0.6
It is about ~1V. As a result, even if the load is nonlinear, the output voltage e _put has the advantage that distortion does not occur because the dip voltage caused by the transistor is generated in proportion to the voltage applied between the input terminals 19 and 20. However, when no dip voltage is generated, transistors 12 and 13 must be kept on at all times, which causes heat generation in the transistors. Therefore, as seen in the embodiment of FIG. 1, thyristors 17 and 18 are inserted,
A signal for turning these on can be obtained from the control circuit 16. In this way, during normal times,
By turning off transistors 12 and 13, these heat generation can be prevented.

Note that the control circuit 16 includes transistors 12,
13 and the thyristor 17,
A voltage circuit for controlling 18 is included. In the case of AC voltage, small transformers were used in these circuits, and the thyristor was controlled by the voltage obtained from the secondary winding, and the dip voltage was selected by switching the taps of the secondary winding. ing. As can be seen from the above explanation of operation, the control output obtained from this secondary winding simply controls the transistor or thyristor, so power consumption is low, and the transformer used is therefore small and lightweight. It's fine to use one. Furthermore, for DC voltage, a voltage divider circuit using resistors with low power consumption is used, and the control voltage can be selected by switching the taps.

[Effect of idea]

As is clear from the above explanation, according to the present invention, the output voltage is controlled using a transistor,
By turning on the thyristor and supplying output when a normal output voltage is supplied, not only the heat generation of the transistor described above is suppressed, but also it can be made smaller and lighter and more economical when applied to AC voltage. The benefits are great, such as being able to easily apply it to DC voltage by simply changing a portion of the control circuit.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing an embodiment of the present invention, FIG. 2 is a circuit diagram showing an example of a conventional power supply voltage fluctuation generating device, and FIG. 3 is a circuit diagram showing another example of a conventional power supply voltage fluctuation generating device. FIG. In the figure, 11 is a power supply, 12 and 13 are transistors, 14 and 15 are diodes, 16 is a control circuit, 17 and 18 are thyristors, and 23 is a load.

Claims (1)

[Claims for Utility Model Registration] The emitters of a pnp transistor and an npn transistor are commonly connected, the collectors of each are connected via two diodes connected in series in the same direction, and the bases of each pnp transistor and npn transistor are connected in common. a voltage control circuit that generates a voltage with the dip voltage as a reference voltage between the connection point of the two diodes and the common connection point of the emitter, regardless of whether the dip voltage of AC or DC is received during the period; A bypass circuit consisting of two thyristors connected in parallel and with opposite polarities between the common connection point of the emitters of the voltage control circuit and the series connection point of the two diodes, and turned on/off in response to a control voltage. The parallel connection point of the voltage control circuit and the bypass circuit is connected in series between a direct current or alternating current input power source and a load, and the input power source receives the input power source voltage. A voltage detection circuit that outputs a selected DC or AC voltage proportional to the input power supply voltage as the dip voltage by selectively using a voltage dividing circuit in the case of DC or a transformer in the case of AC, and the control A power supply voltage fluctuation generating device comprising a control circuit having a voltage circuit that generates a control voltage that turns on two thyristors of the bypass circuit when a normal voltage is supplied and turns them off at other times.