JPS60213266A - Resetter of protecting circuit - Google Patents

Abstract

PURPOSE:To shorten a waiting time up to the reclosing of a power source by connecting a level shifting Zener diode through a diode directly with an AC power source and commutating a thyristor conducted at the abnormal time therewith. CONSTITUTION:The resetter of a protecting circuit rectifies an AC power source 7 via diodes 16 and level-shifts it via a Zener diode 17. An electrolytic condenser 19 is charged by the current flowed through the diode 17, the voltage is divided by resistors 20, 21, and applied to a transistor (Tr)22. When a malfunction occurs in a control circuit 2 in this state to cause a thyristor 3 to be conducted, an electrolytic condenser 23 is discharged, and when an AC switch 5 is opened OFF due to the recovery, the condenser 23 is discharged to turn OFF the Tr22. Thus, when the switch 5 is reclosed, the Tr22 is immediately turned ON to cause the thyristor 3 to be reversely biased. Accordingly, the thyristor 3 is turned OFF to start the control circuit 2.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application: The present invention relates to a switching regulator used in electronic equipment.

Conventional example 4 (°% composition and its problems) Conventionally, in a switching regulator as shown in FIG.
It has the function of detecting the current of . Sot+-'(c) is applied to the gate of the thyristor 3 to make the thyristor 3' conductive, lowering the bias voltage applied to the control circuit 2 through the starting resistor 4, and stopping the drive pulse output from the control circuit 2. There was Sase-C.

However, the conventional circuit shown in FIG. 1 has the following drawbacks.

First, since the thyristor 3 has a self-holding property, in order to return from the conductive state, the supply voltage must be removed once, and the flowing current must be reduced to below the holding current of the thyristor 3. Normally, the AC switch 5 is turned off. By turning off, the supply voltage is removed, but '(Ii 'I!I Contenza 6VC equivalent Nayaan is 8-) - due to its charging energy -) - CMuL Ruichi Iristor 3's voltage. Until θIL becomes less than the holding current VC (, "J/V")
There are up to 1 of tJ tatami and lI+1, and 2 control circuits do not start.

Control circuit 2 failure/restart KC, quite long 11
After one, 7CA C switch 5 must be turned on to 1,
No.

In addition, in Fig. 1 VC, 7 is an AC' [L source, 8 is a rectifier that becomes a rectifier and 1' slip FjlS, 9 and 10 are resistors, and 11
&ma is the output section.

As an improvement over the conventional example, the circuit shown in FIG. 2 VC has been proposed as shown in FIG.

2 The voltage applied to the starting resistor in Figure 2 VC is AC'11
From L 7, a diode 13 and an electric current 6+ are added by the 14vC. By setting the electrolytic content 14 to be considerably smaller than the electrolytic capacitor 6, after turning off the AC switch 6, the electrolytic capacitor 14 immediately conducts VC), and the thyristor 3 is brought into an open state. I'l) Waiting time for startup is almost eliminated.

However, as shown in Figure 3, the 100V system and the 200V system
For the human power of the v system, by switching the 11′L flow circuit, for the r=,
If it is, a current similar to that shown by the arrows A1 to A4 (C/do) flows, and a voltage is applied to the starting resistor 12 by the large capacitance current (I1L) from the capacitor 16, and the thyristor 3 ( (1) (not shown) maintains the conductive state for a considerably long time, and the initial drawbacks are not improved at all.

OBJECTS OF THE INVENTION In view of the above-mentioned drawbacks, the present invention has been designed to provide an alternative operation, etc.
The present invention provides a reset device for a protection circuit that has a short waiting time when turning on the AC power again in order to clean up a generator that has been stopped.

Structure of the Invention In order to achieve the above object, the present invention connects a level/node diode directly to the alternating current illumination through the diode ζ1, and obtains a signal indicating the presence or absence of the M overpressure by means of its rL. It operates in the event of an abnormality in the suinoting legi leak and commutates the fc-reli risk.

DESCRIPTION OF EMBODIMENTS The following is a description of the protection circuit according to an embodiment of the present invention.
The details of the device V will be explained with reference to the drawings.

The diode 16 is used to rectify the AC power source 7, and the Zener diodes 1 and 17 are used to convert the DC level to 1 ooV.
This is to prevent current from being generated by charging the electrolytic capacitor 15 when the AC switch is turned off when it is set to yarn input. When selecting the voltage of the Zener diode 17, the voltage of the solution capacitor and t;L may be the same. In Fig. 3, even if a Zener diode is inserted in series with the diode 13, the same result will not be obtained, but this part V'C is connected to the starting resistor when the current for operating the control circuit 2 is passed. flows, so a Zener diode with a large wattage is safe, which is a big disadvantage in terms of cost. In Figure 4, 10, the current obtained through Zener diode 17, resistor 18'f
r: The electrolytic capacitor 19 is then charged. Then, the voltage divided by the resistor 20.21 is divided by the transistor 2.
2, so when the AC switch and chiro are on, the transistor 22 is on.

At this time, the capacitor 23 is charged at the anode side of the thyristor 3. Is there something wrong with the control circuit 2 in this state? :; If it is detected and the thyristor 3 is turned on 4 times, will the capacitor 23 be discharged? Ji L'i1.
1 in t JL is almost zero. When the AC switch 6 is turned off to restore the power, the electrolyte in the '1' capacitor 19 traces through the resistors 20 and 21 and is immediately discharged. Therefore, the transistor 22 is turned off and the capacitor "+23 r, i
The side of transistor 22 is charged to +. Next, when the AC switch 6 is turned on to turn on (11), the voltage/dimeter 22 is immediately turned on, applying the ten potential of the content 23 to the cathode of the thyristor 3, making it reverse biased.
At c, the thyristor 3 becomes I and V, and the control circuit V
c A starting voltage is applied to start up.

Here, even if a thyristor such as KPLJT is used instead of thyristor 30, the same result will be obtained. In this way, with the circuit shown in FIG.
The waiting time when turning off the switch 5 once is negligible, and the VC can be ignored, and the 1iU short width is very useful when checking abnormal operations during process inspections.
Note that in FIG. 4, 24 is a resistor.

Effects of the Invention As described above, according to the present invention, 1
The waiting time until the AC power supply is turned on again in order to return to the stopped ignition J]i4 can be made so short that it can be almost ignored.

[Brief explanation of drawings]

1 and 2 are circuit diagrams of a reset device for a conventional γL protection circuit, FIG. 3 is a circuit diagram of a main part of a reset device for another conventional protection circuit, and FIG. 4 is an embodiment of the present invention. FIG. 2 is a circuit diagram of a Leahy-tan device of a protection circuit in an example. 1... Switching transistor, 2... Control circuit (control section), 3... Zyristor, 7...
... AC power supply, 8 ... Rectifier (rectification smoothing section), 16 ... Diode, 17 ... Zener diode. Name of agent: Patent attorney Toshio Nakao and 1 other person 1 Figure 2 Figure 1 ″122

Claims (1)

[Claims] A rectifying and smoothing section is connected to the AC power source, and a control section is connected to adjust the rectifying and smoothing section [to which an i-transformer transformer and a switching transistor are connected, and the pulse 11 given to the switching transistor]. Directly connect a diode and a Zener diode for level shifting, and connect to the control section above based on the AC voltage presence signal obtained by the Zener diode.
A protection circuit reset device that rotates the thyristor by 1° when the switching regulator is activated.