JPH0741473U - Discharge rod with discharge level display function - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a discharge rod having a discharge level display function capable of discharging a high voltage capacitor while displaying the residual charge of the high voltage capacitor. [Structure] The discharge current when the high voltage accumulated in the high voltage capacitor 1 of the high voltage power receiving equipment is discharged to the ground through the discharge high voltage resistor 2 and the discharge current detection resistor 3 is dropped by the discharge current detection resistor 3. And compares the detected voltages with the first, second and third reference voltages in the first, second and third comparison circuits 5a, 5b and 5c, respectively.
Based on this comparison result, the first, second and third light emitting diodes 6a, 6b, 6c are driven, and the voltage remaining in the high voltage capacitor 1 is identified by the light emitting states of these light emitting diodes 6a, 6b, 6c. can do.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a power factor improving capacitor for high-voltage power receiving equipment, that is, a discharge rod that discharges residual electric charge of a capacitor such as a high-voltage phase-advancing capacitor through a high-voltage resistor. The present invention relates to a discharge rod having a discharge level display function for displaying the remaining electric charge.

[0002]

[Prior art]

 As a general rule, the operation of high-voltage power receiving equipment is stopped every year and the performance of insulation resistance and protective relays is tested.

In carrying out such work, in order to ensure safety, in order to discharge the high voltage remaining in the high voltage capacitor, a discharge rod is connected to the high voltage capacitor, and the high voltage resistance of the discharge rod is changed. The work is performed to discharge the high voltage remaining in the high-voltage capacitor to the ground via the via.

In this discharging operation, it is important to keep the discharge rod connected to the high voltage capacitor until the voltage remaining in the high voltage capacitor falls below a predetermined safe low voltage. For this reason, conventionally, the time required for discharging is calculated from the electrostatic capacity of the high-voltage capacitor and the high-voltage resistor for discharging, and the discharge rod is connected to the high-voltage capacitor during this time.

[0005]

[Problems to be solved by the device]

 As described above, when the conventional discharge rod is used, the discharge rod is connected to the high-voltage capacitor during the discharge time calculated from the electrostatic capacity of the high-voltage capacitor and the high-voltage resistance for discharge, Since discharge work is performed, there is a problem that it is necessary to always discharge for a certain period of time regardless of the presence or absence of the voltage remaining in the high-voltage capacitor, and it is not possible to confirm that the discharge has been completed reliably. .

The present invention has been made in view of the above, and an object thereof is a discharge rod having a discharge level display function capable of discharging a high voltage capacitor while displaying a residual charge of a high voltage capacitor. To provide.

[0007]

[Means for Solving the Problems]

 In order to achieve the above object, a discharge rod having a discharge level display function of the present invention is a discharge rod that discharges the residual electric charge of a high voltage capacitor provided in a high voltage power receiving equipment through a high voltage resistor. A current detection resistor that is connected in series with a resistor and that detects a discharge current discharged through the high-voltage resistor, and a charge remaining in the high-voltage capacitor based on the discharge current detected by the current detection resistor are displayed. The gist is to have a display means.

[0008]

[Action]

 In the discharge rod having the discharge level display function of the present invention, the discharge current of the high voltage capacitor discharged through the high voltage resistor is detected by the current detection resistor, and the electric charge remaining in the high voltage capacitor is detected based on the detected discharge current. Is displayed.

[0009]

【Example】

 Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a circuit diagram showing a structure of a discharge rod having a discharge level display function according to an embodiment of the present invention. The discharge rod with the discharge level display function shown in the figure is installed in the high-voltage power receiving equipment when the operation of the high-voltage power receiving equipment is stopped and the performance test of insulation resistance and protective relay is to be performed. It is used to discharge the electric charge remaining in the high-voltage phase-advancing capacitor, which is a power factor improving capacitor, and other high-voltage capacitors, that is, the accumulated high voltage from the standpoint of safety. A discharge rod indicated by 10 in FIG. 1 is connected to a terminal 1a of a high-voltage capacitor 1 of a high-voltage power receiving equipment via a lead wire 9, and a high voltage, which is a charge remaining in the high-voltage capacitor 1, is discharged from the terminal 1a. It discharges to the ground through the lead wire 9, the discharge high-voltage resistor 2, and the discharge current detection resistor 3.

Then, in this case, the discharge current flows through the discharge current detecting resistor 3 to detect the voltage generated in the discharge current detecting resistor 3 as the discharge current, and based on the detected voltage, the high voltage capacitor is detected. The voltage accumulated in 1 is judged. More specifically, the voltage proportional to the discharge current generated in the discharge current detection resistor 3 is supplied to the first, second and third comparison circuits 5a, 5b and 5c after the noise component is removed by the filter 4. And compared with the first, second and third reference voltages, respectively. The output signals from the first, second and third comparison circuits 5a, 5b, 5c are supplied to the first, second and third light emitting diodes 6a, 6b, 6c, and the light emitting diodes 6a, 6b, The display of 6c shows how much the voltage stored in the high voltage capacitor 1 is discharged. In FIG. 1, numeral 7 is a power supply for supplying an operating voltage to each part of the discharge rod 10.

In the discharge rod having the discharge level display function configured as described above, the first, second and third reference voltages of the first, second and third comparison circuits 5a, 5b and 5c are If the voltages stored in the high-voltage capacitor 1 are, for example, 100 V, 30 V, and 5 V, and are set to voltages V ₁ , V ₂ , and V ₃ , respectively, the first, second, and The comparator circuits 5a, 5b, and 5c of No. 3 generate a voltage (hereinafter, referred to as a compared voltage) generated in the discharge current detection resistor 3 supplied through the filter 4 into the first, second, and third voltages. When the compared voltages are respectively compared with the reference voltages V ₁ , V ₂ and V _3, and the compared voltages are higher than the first, second and third reference voltages V ₁ , V ₂ and V ₃ , the comparison circuits 5a, 5b and 5c output signals to the first, second and third light emitting diodes. To the first, second, and third light emitting diodes 6a, 6b, 6c.

Now, assuming that the voltage accumulated in the high voltage capacitor 1 (hereinafter referred to as residual voltage) is, for example, 200 V, the compared voltage across the discharge current detecting resistor 3 corresponding to this residual voltage 200 V is , The reference voltages V ₁ , V ₂ and V _{3 of the} comparison circuits 5a, 5b and 5c corresponding to the residual voltages of 100V, 30V and 5V are higher than the reference voltages V ₁ , V ₂ and V ₃ , respectively. It is understood that the diodes 6a, 6b and 6c are supplied to each of the light emitting diodes 6a, 6b and 6c to emit light, and the residual voltage of the high voltage capacitor 1 is at least greater than 100V.

Next, the residual voltage of the high-voltage capacitor 1 is further discharged through the discharging high-voltage resistor 2 and the discharge current detection resistor 3 of the discharge rod 10, and as a result, the residual voltage of the high-voltage capacitor 1 drops to, for example, 70V. Then, the compared voltages across the discharge current detecting resistor 3 corresponding to the residual voltage 70V are the reference voltages V ₁ , V ₂ , V ₃ corresponding to the residual voltages 100V, 30V, 5V and the comparison circuit 5a. , 5b, 5c respectively, but in this case, it is smaller than the reference voltage V ₁ of the first comparison circuit 5a and smaller than the reference voltages V ₂ , V _{3 of} the second and third comparison circuits 5b, 5c. Therefore, the first comparison circuit 5a does not supply the output signal to the first light emitting diode 6a, and only the second and third comparison circuits 5b and 5c output the output signal to the respective light emitting diodes 6b and 6c. Supply. As a result, the first light emitting diode 6a does not emit light, and only the second and third light emitting diodes 6b and 6c emit light, whereby the residual voltage of the high voltage capacitor 1 is at least less than 100V and less than 30V. It turns out that it is larger than.

If the residual voltage of the high-voltage capacitor 1 is further discharged and the residual voltage of the high-voltage capacitor 1 is reduced to, for example, 20V, the same applies to the first, second and third comparison circuits 5a, 5b and 5c. By the comparison operation, the first and second light emitting diodes 6a and 6b do not emit light, and only the third light emitting diode 6c emits light. Therefore, the residual voltage of the high voltage capacitor 1 is smaller than 30V. It turns out that it is larger than 5V.

When the high voltage capacitor 1 is further discharged, and as a result, none of the first, second and third light emitting diodes 6a, 6b, 6c of the discharge rod 10 emits light, the high voltage capacitor 1 It can be seen that the residual voltage has dropped to 5 V or less.

As described above, to what extent the residual voltage of the high voltage capacitor 1 is discharged can be identified by the light emitting states of the first, second and third light emitting diodes 6a, 6b, 6c. Therefore, in addition to ensuring safety, the light emitting diode 6a does not have to be continuously discharged for a period of time calculated from the capacitance of the high-voltage capacitor 1 and the high-voltage resistor 2 for discharge. , 6b, 6c, it is possible to appropriately stop the residual voltage when it is found that the residual voltage has dropped to a predetermined voltage or less, and the discharge work can be shortened.

In the above embodiment, the first, second and third light emitting diodes 6a, 6b, 6c emit light when the residual voltage of the high voltage capacitor 1 is high, and as the residual voltage decreases, the first Although the light emitting diodes 6a are configured to sequentially stop emitting light, conversely, the light emitting diodes 6a may sequentially emit light as the residual voltage of the high voltage capacitor 1 decreases.

Also, instead of using the light emitting diodes 6a, 6b, 6c, various display means, such as using a meter such as a voltmeter, or using a digital display, various methods are conceivable. Is.

Further, in the above embodiment, the residual voltage of the high voltage capacitor 1 is detected by using the discharge current detecting resistor 3, but the present invention is not limited to this, and for example, a current transformer or the like is used. It is also possible to do so.

[0021]

[Effect of device]

 As described above, according to the present invention, the discharge current of the high-voltage capacitor discharged through the high-voltage resistor is detected by the current detection resistor, and the high-voltage capacitor remains based on the detected discharge current. Since the electric charge is displayed, the voltage remaining in the high-voltage capacitor can be identified during the discharge work, which can ensure safety and improve the efficiency of the discharge work.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a structure of a discharge rod having a discharge level display function according to an embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 high-voltage capacitor 2 high-voltage resistance for discharge 3 resistance for discharge current detection 5a, 5b, 5c 1st, 2nd and 3rd comparison circuits 6a, 6b, 6c 1st, 2nd and 3rd light emitting diode 10 discharge level display Discharge rod with function

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication location H02J 1/00 309 J 7429-5G 3/18 C 7522-5G

Claims (1)

[Scope of utility model registration request] 1. A discharge rod for discharging residual electric charge of a high-voltage capacitor provided in high-voltage power receiving equipment through a high-voltage resistor, the discharge rod being connected in series to the high-voltage resistor and discharging through the high-voltage resistor. A current detection resistor for detecting the current,
A discharge rod having a discharge level display function, comprising: a display unit for displaying the electric charge remaining in the high voltage capacitor based on the discharge current detected by the current detection resistor.