CN2202989Y

CN2202989Y - Ground insulation monitoring protector

Info

Publication number: CN2202989Y
Application number: CN 93230813
Authority: CN
Inventors: 唐延明; 李瑞云
Original assignee: RODLESS OIL PRODUCTION PUMP CO SHENGLI PETROLEUM ADIMINISTRATION BUREAU
Current assignee: RODLESS OIL PRODUCTION PUMP CO SHENGLI PETROLEUM ADIMINISTRATION BUREAU
Priority date: 1993-04-24
Filing date: 1993-04-24
Publication date: 1995-07-05
Anticipated expiration: 2003-04-24

Abstract

The utility model relates to a protective device for the insulating property automatic monitoring of an electrical appliance apparatus system, which can do on-line continuous automatic measurement. The utility model is characterized in that a control cabinet and a machine set are respectively connected with a high-voltage isolator, an insulation resistance test system and a protection instrument. The utility model can set a setting value for doing fixed point protection according to the physical circumstance of electrical equipment, avoids the large area spark through damage of equipment, cables, etc., because of the decreasing of insulate resistance, and avoids accidents.

Description

Ground insulation monitoring protector

The utility model is a kind of protective device that insulating properties is monitored automatically of electrical equipment equipment system.

It is existing that to be usually used in measuring high-resistance instrument be portable megohmmeter; also be megger; or use the electronics megohmmeter; this type of instrument can only be measured its insulating resistance value after closing the power supply of power consumption equipment; measure and can not carry out on-line continuous, also just can not avoid power consumption equipment, equipment protected before the large tracts of land punch through damage effectively.Especially monitor and protect even more important to long-term work in the insulation property of high temperature, high pressure, submersible electric machine with oil equipment that corrosivity is strong, cable etc.

The utility model provides a kind of online auto monitoring protective device; and power consumption equipment, equipment do not have the problem of insulation protection; the insulation property of energy online auto monitoring electric pump unit and so on; and setting value is set according to the concrete condition of electric equipment; fix a point to protect, avoided reducing the equipment that causes, cable etc. by the large tracts of land punch through damage because of insulation resistance value.

Insulating monitoring fixed point protective device mainly is made up of following several parts, and high-voltage isolator, insulation resistance test system are arranged, and connects machine with adopting micro-processor controlled protection instrument.The fixed point protection is set, reaches the insulation values of the relevant unit equipment of long-term monitoring automatically, make operating unit equipment long-term work in the place of safety of insulation values.

Further describe below in conjunction with accompanying drawing, Fig. 1 is connection side's block diagram of this device, and Fig. 2 is protection instrument panel figure, and Fig. 3 is the insulation resistance test system structure chart.As Fig. 1; with A; B; the C three phase mains is introduced control cubicle (1); export through control cubicle (1); the cable of leading up to is received motor (2); high-voltage isolator (3) is received on another road; three groups of coils of its inductance are with Y-connection; asterism joins with the test dc high-voltage source; high direct voltage just can be added to tested electromechanical equipment like this; cables etc. are located; promptly be added in the measured signal; insulation resistance test system (4) is under protection instrument (5) control, and after the sampling loop sampled signal arrived protection instrument (5) processing again, protection instrument (5) sent the operating state of signal with decision unit (2) to control cubicle (1).And ac high-voltage disturbs because of the inductor coil impedance can't seal in high voltage direct current generator greatly, thereby has realized the isolation ac high-voltage and perfectly straight stream.High-voltage isolator (3) is made up of high voltage induction and electric capacity, according to the electrotechnics principle, the amplitude of three phase sine electromotive force equates, phase difference is 120 °, be added in the load with identical parameters when three-phase electricity, and during with Y-connection, its asterism alternating voltage is zero, therefore realized the purpose of isolated high-voltage, this high-voltage isolator is that coil by E shape iron core and three groups of identical parameters is with the Y-connection coiling, and its asterism lead-in wire and high direct voltage output joined, form the test loop of test insulation resistance.The protection instrument of Fig. 2 is to adopt social existing equipment and this device that supporting use is installed.Numeral shows that (6), indicator light (7) are shown as operation, underload, overload, situation such as single-phase, auxiliary respectively; being installed on opposite side by key control (8), binding post (9) links to each other with test macro and control flow; by protection instrument and test macro terminals AC power is introduced in the test macro; and control and treatment signal and carry out digital processing, show the insulating resistance value of surveying by display circuit.Insulation resistance test system mainly is made up of high voltage direct current generator and sample of signal two parts, tested insulation resistance Standard resistance range is in 0.001 to 99.9 megaohm, signal processing is at 0.001 to 10 volt, in addition, measured resistance direct voltage that two ends add is at 500 to 2500 volts, this just needs the design high pressure generator, will be AC power to its rectification, filtering voltage regulation (13), push-pull oscillator circuit (14) by two above triodes are formed through the oscillation transformer that boosts (15), promotes alternating voltage again, again through high pressure bridge rectifier filtering (16) and voltage stabilizing (17), rectification can obtain high-precision high direct voltage with 2 above diodes, voltage stabilizing with 2 above voltage-stabiliser tubes, when adopting the proof load of voltage-stabiliser tube energy to change greatly, selected high direct voltage is a steady state value.Sampling loop (18) is made of sample resistance, protective resistance and measured resistance series connection, measured resistance one end ground connection, and sample resistance one end is ground connection also, connects protective resistance between sample resistance and measured resistance.This protective resistance is when measured resistance is too small; prevent that loop current is excessive and damage element; limit the electric current of the sample resistance of flowing through in addition; the signal of sampling loop (18) is delivered to signal processing (19); signal makes its output corresponding one by one with measured resistance through relatively amplifying; this analog signal is delivered to protection controller (5) and is carried out analog-to-digital conversion again through showing processing, until the actual resistance that demonstrates measured resistance.Instrument terminals (21) after tested, the control signal that protection instrument (5) is sent to control sampling part (20) with sampling period of control sampling loop (18) and number of times etc.

In addition, this overlaps test macro, also is provided with a low-voltage power supply and partly supplies integrated work, is input into alternating current and reduces to low-voltage AC through transformer (10), constitutes one the tunnel through rectifying and wave-filtering (11) and voltage stabilizing (12), forms low-tension supply.

For example, when using this device to carry out the on-line continuous measurement, promptly when the unit operate as normal, need not powered-down and just can measure the relevant insulation situation of unit equipment at that time that shows, owing to adopted high-voltage isolator, high direct voltage is added on the unit equipment of operation always carries out online auto monitoring.Be in particular in the protection instrument situation that shows A, B, C three-phase current and insulating resistance value capable of circulation, in case but surpass just stoppage protection of the safety value set.

In addition, when causing the variation of insulation property owing to rainy or some other factor, can be by resetting the purpose that setting value reach the protection electromechanical equipment.Be set to 5 megaohms as certain unit insulation setting value; state all situations and make decreasing insulating to 5 megaohms when following when long playing electric pump unit meets; this covering device then can automatically shut down power supply; and demonstrate shutdown insulation resistance value of preceding moment, so just can reset rational setting value and continue monitoring and protecting.

Claims

1, insulating monitoring fixed point protective device is a kind of protective device of electrical equipment equipment; it is being connected high-voltage isolator, insulation resistance test system and protection instrument respectively by control cubicle and unit; its feature high-voltage isolator is made up of high voltage induction and electric capacity; insulation resistance test system partly is made up of high voltage direct current generator and sample of signal, and the protection instrument is connecting insulation resistance test system and high-voltage isolator.

2,, it is characterized in that coil by E shape iron core and three groups of identical parameters with the Y-connection coiling, and its asterism lead-in wire and high direct voltage output are joined by the high-voltage isolator of the described insulating monitoring of claim 1 fixed point protective device.

3, press the insulation resistance test system of the described insulating monitoring fixed point of claim 1 protective device; it is characterized in that testing the scope of insulation resistance in 0.001 to 99.9 megaohm; sampled signal is at 0.001 to 10 volt, and measured resistance direct voltage that two ends add is 500 to 2500 volts.

4, press the insulation resistance test system of claim 1 and 3 described these devices, it is characterized in that through voltage stabilizing (13), by the push-pull oscillator circuit (14) of two above triodes compositions with through the oscillation transformer that boosts (15), again through high pressure bridge rectifier filtering (16) and voltage stabilizing (17), rectification is with 2 above diodes, and voltage stabilizing is with the voltage-stabiliser tube more than 2.

5, press the insulation resistance test system of claim 1 and 4 described these devices; it is characterized in that sampling loop (18) is made of sample resistance and protective resistance and measured resistance series connection; the signal feed signals of sampling loop (18) is handled (19), and the control signal transported to of instrument terminals (21), protection instrument (5) is to control sampling part (20) control sampling loop (18) after tested.

6, by the insulation resistance test system of claim 1 and 5 described these devices, its feature low-voltage power supply partly is that alternating voltage constitutes one the tunnel through step-down transformer (10), rectifying and wave-filtering (11) and voltage stabilizing (12).