CN2755615Y

CN2755615Y - Non-residual pressure on-line monitor

Info

Publication number: CN2755615Y
Application number: CN 200420093374
Authority: CN
Inventors: 邹积俊
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-09-08
Filing date: 2004-09-08
Publication date: 2006-02-01
Anticipated expiration: 2014-09-08

Abstract

The utility model relates to a non-residual pressure on-line monitor for arresters and non-residual pressure monitoring technique. The utility model has the technical scheme of adopting a high-frequency pulse current mutual inductor and a 50Hz power frequency current mutual inductor, which separately pick up lightning wave pulse current signals and AC 50Hz current signals from a grounding wire of the arrestor through an induction mode. Picking up the current signals through the induction mode can not generate residual pressure and can completely insulate a monitor and the arrester for not influencing each other and making the grounding end of the arrester to be normally grounded and to lie in zero potential all the time. The utility model is an ideal and optimum proposal which realizes non-residual pressure monitoring, and hence, the arrestor no longer has forbidden zones in the technical field of on-line monitoring which can be carried out as long as the arrestor is applied. The technical scheme of the utility model is considered as great breakthrough in the monitoring technology of arrestors and is an essential product of technology renewal and product replacement, and the utility model can inevitably replace residual pressure monitoring technology.

Description

No residual voltage on-line monitoring device

Technical field

The utility model is about exchanging the instrument of gapless metal-oxide lighting arrester (abbreviation lightning arrester) on-line monitoring.

Background technology

At present, what electric system was used is a kind of monitor that residual voltage is arranged, this monitor has produced 3KV voltage (abbreviation residual voltage) at the monitor two ends when the discharge of record lightning arrester makes arrester ground terminal also have 3KV voltage rather than zero status, therefore its application has the forbidden zone, worries to press the stack back to puncture winding and dare not use as the lightning arrester of genset outlet.

Summary of the invention

The purpose of this utility model is to release a kind of no residual voltage monitoring technology scheme, guarantees the normal ground connection of lightning arrester, and its ground terminal is in zero potential all the time.

The utility model is achieved through the following technical solutions

The utility model adopts high-frequency pulse current transformer inductive pick-up lightning wave pulsed current signal, and transformer induced the picking up of power current exchanges the 50HZ current signal, realizes no residual voltage sample of signal, thereby realizes no residual voltage monitoring.

Description of drawings

1, Fig. 1 is the synoptic diagram that residual pressure monitor is arranged, monitor input end and earth terminal insert a valve block RU (abbreviation of zinc oxide varistor) as can be seen from Figure, and arrester ground terminal will be through this valve block ability ground connection, when discharge current by the time valve block two ends certainly lead to voltage drop, residual voltage that Here it is, therefore it also is the voltage of arrester ground terminal, should be the increment that the ground terminal of zero potential but presents the monitor residual voltage.

The purpose that adds this valve block is to pick up the lightning wave current signal for dividing potential drop, valve block is connected with lightning arrester, in fact lightning arrester self is made of tens of times and even hundred times of valve blocks to RU, so just formed 1/tens or centesimal dividing potential drop ratio, take out from the RU upper end, enter the Q1 bridge rectifier circuit, through C1, R1, the action of C2 filtering rear drive message register, record lightning arrester discharge time.

Q2 is a bridge rectifier circuit, is to take out the power current signal from the RU upper end, enters reometer after C3, R2, C4 filtering, shows the lightning arrester persistent current.L prevents that lightning wave from scurrying into and the radio frequency choke established among the figure.

RL is a message register, and mA is the electric current gauge outfit.

2, Fig. 2 is the electrical schematic diagram of non-residual pressure monitor, as can be seen from the figure L1 is a high-frequency pulse current transformer, inductive pick-up lightning wave pulsed current signal from the arrester ground line, through the full-wave rectification of D1, D2, C1, C2 composition, again through C3, R3, C4, C5 filtering rear drive message register action record lightning arrester discharge time.R1 is a voltage dependent resistor (VDR), is to establish for holding circuit tolerance heavy current impact, and R2 establishes for shaping pulse.

L2 is a power frequency 50HZ AC current transformer, also is inductive pick-up power current signal from the arrester ground line, after L3 and W enter the electric current gauge outfit, shows the persistent current of lightning arrester through D3 half-wave rectification, C7 filtering.C6 is the high-frequency impulse filter capacitor among the figure, and L3 is a radio frequency choke, and the both establishes for preventing that high frequency from scurrying into, and W is a calibration gauge outfit potentiometer, and D4 prevents that pulse current from impacting gauge outfit and establish.

Embodiment

Embodiment is described in detail the utility model below in conjunction with accompanying drawing

1, adopt high frequency ferrite magnetic material iron core, design is also made the pulse current mutual inductor, as L1 among Fig. 2.This mutual inductor efficient height can pick up the pulsed current signal of abundance from the arrester ground line.

2, for picking up maximum power current signal, I select for use the permalloy low-frequency magnetic material of high permeability to make iron core, design and produce highly sensitive power current mutual inductor, as the L2 among Fig. 2.L2 picks up the 50HZ ac current signal from the arrester ground line, shows persistent current for the direct current gauge outfit behind rectifying and wave-filtering, and this electric current belongs to the clamp on amperemeter circuit in fact.

3, for guaranteeing that big electric current (4/10 μ S 100KA peak value) impacts resistance test and reaches a standard, I have adopted the piezoresister (R1) of lightning arrester special use to be connected in parallel on the L1 two ends, form circuit overcurrent protection, to guarantee the circuit reliably working.

4, for guaranteeing the precision and the reliability of electric current gauge outfit, the direct current gauge outfit that I select for use Japanese Yokogawa company technology to produce, this gauge outfit indicator rotating part adopts pull spring supporting way, thus than hairspring mode antivibration, shock resistance, guarantee reliability.

5, for making product not be subjected to age limit, all units, device all adopt the kind of no age limit in the circuit, guarantee that product forever uses.

Claims

1, a kind of no residual voltage on-line monitoring device, in outer cover of steel plate, high-frequency pulse current transformer, counter driving circuit, message register are electrically connected in proper order; Power current mutual inductor, current rectifying and wave filtering circuit and reometer are electrically connected in proper order, it is characterized in that: two shared same input ends of current transformer, and input end is that electromagnetic induction is connected with output terminal, the high-frequency pulse current transformer output terminal is electrically connected with counter driving circuit input end, and its circuit output end is electrically connected with message register; Power current mutual inductor output terminal is electrically connected with the current rectifying and wave filtering circuit input end, and its circuit output end is electrically connected with reometer.

2, no residual voltage on-line monitoring device according to claim 1, it is characterized in that: two shared input ends of current transformer are leads that pass two annular coil axle center that are arranged in parallel successively, one end of line leads to lightning-arrest ground terminal, the other end leads to ground wire terminal, mutually insulated between lead and the coil, between coil and the coil.

3, no residual voltage on-line monitoring device according to claim 1 is characterized in that: high-frequency pulse current transformer adopts the ring-like magnetic material of high frequency ferrite; The power current mutual inductor adopts the ring-like magnetic material of permalloy.