KR0129380Y1 - Error load sensing circuit for electric filter power - Google Patents

Abstract

The present invention relates to an abnormal load detection circuit of the electrostatic precipitating filter power supply, and to solve the problem of the malfunction of the microcomputer due to the electrical noise of the electrostatic precipitating filter power supply and the electrostatic precipitating filter, Abnormal load in DC high-voltage power supply means by providing an abnormal load detection circuit of the electrostatic precipitating filter power supply with an abnormal load detection means for detecting and latching an abnormal load signal generated by the dust collection filter and outputting a relay control signal for separating from the microcomputer power supply. If the load is detected, the power supply itself is cut off without being connected to the microcomputer, which may cause the microcomputer to malfunction due to an abnormal load of the electrostatic precipitating filter.

Description

Abnormal load detection circuit of electrostatic precipitating filter

1 is a control block diagram of the electrostatic precipitating filter unit according to the prior art.

FIG. 2 is a circuit diagram of an abnormal load sensing means in FIG.

3 is a block diagram for detecting an abnormal load of the electrostatic precipitating filter power supply according to the present invention.

4 is a circuit diagram of FIG.

* Explanation of symbols for main parts of the drawings

1: micom 2: relay

3: DC high voltage power supply means 4: Abnormal load detection means

4a: overload detection section 4b: latch and reset section

4c: relay control unit 5: electrostatic precipitating filter

6: converter R1-R7: resistance

C1-C7: Capacitor D1-D5: Diode

ZD2: second Zener diode Q1-Q4: first to fourth transistor

T: Transformer SW: Discharge Switch

The present invention relates to an abnormal load detection circuit of the electrostatic precipitating filter power supply, in particular, to block the high voltage output by sensing the overcurrent flowing in the electrostatic precipitating filter ionizing unit short circuit.

The abnormal load detection of the electrostatic precipitating filter power supply of the prior art, as shown in FIG. 1, the microcomputer 1 operates the relay 2 to the DC high voltage power supply means 3 of the electrostatic precipitating filter (5). When the abnormal load is detected by the abnormal load detection means 4 of the DC high voltage power supply means 3, the signal is transmitted to the microcomputer 1 so that the microcomputer 1 receives the DC high voltage power supply means 3. It is configured to control the power supply of on and off.

The circuit of the abnormal load detection means 4 with the power supply of the electrostatic precipitating filter 5 of the prior art is configured as shown in FIG. 2, and the operation thereof is as follows.

First, when the microcomputer 1 turns on the relay 2 and applies power to the DC high voltage power supply means 3, the converter circuit 6 inside the DC high voltage power supply means 3 starts to operate and transmits the transformer T 1. Since a high frequency AC voltage is applied to the vehicle side, a high frequency high voltage is induced on the secondary side of the transformer (T).

At this time, the induced voltage is smoothed by the condenser C6, converted into a DC high voltage, and used as a power source of the electrostatic precipitating filter 5.

Therefore, when a streamer discharge or a spark discharge occurs in the ionizing part of the electrostatic precipitating filter 5, a large amount of current flows in the upper coil of the secondary side of the transformer T. Induce voltage.

At this time, when the induced voltage is higher than the zener voltage of the zener diode ZD2, the zener diode ZD2 is in a conductive state and current flows through the photo coupler PC, and the signal is transferred to the microcomputer 1, and such an abnormal signal. The microcomputer 1 wound around turns off the relay 2 to cut off the power applied to the DC high voltage power supply means 3.

Since the abnormal load detection means of the prior art processes the abnormal load detection signal in the microcomputer 1, the microcomputer 1 malfunctions due to the electrical noise generated during the abnormal load of the high voltage. Since it is necessary to electrically separate the means 3 from the microcomputer controller, it is necessary to detect the load by the DC high voltage power supply 3 itself and stop the operation when an abnormal load is detected.

Accordingly, an object of the present invention is to provide an abnormal load detection circuit of an electrostatic precipitating filter power supply for detecting an abnormal load in a DC high voltage power supply means to cut off power.

Technical means of the present invention for achieving the above object, the abnormal load detection means for outputting a relay control signal for detecting and latching the abnormal load signal generated in the electrostatic precipitating filter in the electrostatic precipitating filter and separated from the microcomputer power supply It is a configuration attached.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

First, as shown in FIG. 3, the structure of the present invention is a direct current high voltage power supply means 3 caused by streamer discharge or spark discharge by short circuit of electrode or fouling of electrode at the ionizing part of the electrostatic precipitating filter 5. When the abnormal load is generated, the abnormal signal is detected by the abnormal load detection means 4 to control the relay 2 so as to be separated from the microcomputer 1.

Accordingly, the circuit of the present invention will be described in more detail with reference to FIG.

First, as a component of the present invention, the abnormal load detecting means 4 includes an overload detecting unit 4a using a second zener diode ZD2 to detect and output an overload signal generated by an electrostatic precipitating filter, and the overload. The latch and reset unit 4b is connected to the overload signal output from the detection unit 4a to latch and reset the overload signal, and the relay is operated by the overload signal output from the latch and reset unit 4b. It consists of the relay control part 4c which turns off.

The latch and reset unit 4b is configured to switch the third transistor Q3 for switching according to the signal output from the overload detection unit 4a and the overload signal output through switching of the third transistor Q3. The latch capacitor C7 to charge and latch, and the discharge switch SW to reset the overload signal latched to the latch capacitor C7.

In addition, the relay controller 4c is configured as a fourth transistor Q4 to switch in accordance with a signal output from the latch and reset 4b to output a relay control signal.

Referring to the operation of the present invention by the above configuration as follows.

First, when an abnormal load is generated in the electrostatic precipitating filter 5, since a large amount of current flows in the upper coil of the transformer (T) secondary side, a high voltage is induced in the transformer (T) secondary side lower coil. When the zener voltage of the second zener diode ZD2 is higher than the predetermined zener voltage, the second zener diode ZD2 is in a conductive state and a voltage is applied to the resistor R4 at the bottom of the second zener diode ZD2.

The overvoltage, which is an overload signal applied to the resistor R4, is applied to the third transistor Q3 of the latch and reset section 4b to conduct the third transistor Q3 to charge the latch capacitor C7.

Since the voltage charged in the latch capacitor C7 has no discharge path except for the discharge switch SW, the voltage is applied to the base of the fourth transistor Q4 to turn on the fourth transistor Q4 to turn on the relay 2. The relay 2 is turned off by applying a high (H) signal to the second transistor Q2 connected thereto (see reference numeral A) to turn off the second transistor Q2, which causes the DC high voltage power supply unit 3 to turn off. The applied power is cut off.

The potential latched by the latch capacitor C7 is reset using the discharge switch SW.

The present invention as described above can prevent the malfunction of the microcomputer (1) caused by the abnormal load of the electrostatic precipitating filter can be cut off by itself when the abnormal load is detected in the DC high voltage power supply device without connecting to the microcomputer (1). It can be effective.

Claims (3)

An overload detection section 4a for detecting and outputting an overload signal generated by the electrostatic precipitating filter, and a latch and reset section 4b that is electrically connected to the overload signal output from the overload detection section 4a to latch and reset the overload signal. And a relay control unit 4c which is operated by an overload signal output from the latch and reset unit 4b and relays off to detect an abnormal load signal generated in the electrostatic precipitating filter inside the electrostatic precipitating filter power supply. An abnormal load detection circuit of an electrostatic precipitating filter power supply configured by providing an abnormal load detection means (4) which latches and outputs a relay control signal for separating from a microcomputer power supply. 2. The latch and reset unit 4b according to claim 1, wherein the latch and reset unit 4b is output by switching of the third transistor Q3 and the third transistor Q3 which switch according to the signal output from the overload detection unit 4a. An abnormal load detection circuit of an electrostatic precipitating filter power supply, characterized by comprising a latch capacitor (C7) for latching an overload signal, and a discharge switch (SW) for resetting an overload signal latched by the latch capacitor (C7). 2. The electrical circuit according to claim 1, wherein the relay control section 4c comprises a fourth transistor Q4 for switching in accordance with a signal output from the latch and reset section 4b to output a relay control signal. Abnormal load detection circuit of the dust filter power supply.