A kind of MOA current in resistance property detection system
Technical field
The present invention relates to a kind of MOA (Zinc-Oxide Arrester) current in resistance property detection system.
Background technology
Traditional Zinc-Oxide Arrester detection system is introduced required voltage signal and current signal in the same equipment; Voltage signal is that the secondary side of the capacitance type potential transformer (CVT) from transformer station takes out; Current signal can take out through current transformer from the ground wire of Zinc-Oxide Arrester (MOA); The perhaps lightning stroke counter through the Zinc-Oxide Arrester lower end is clipped in the two ends of lightning stroke counter with current clamp, gets method of current through small resistor resistive total current is taken out.Measuring method is as shown in Figure 1.The voltage of obtaining and current signal are carried out a series of processing obtain resistive current component.
The defective of this metering system is the metering system of voltage signal, need be in the secondary side wiring of CVT in whole measuring process.This has just caused 2 problems:
(1) because CVT is the transformer of a step-down; The short circuit meeting of secondary side in operating process causes passing through of big electric current; Make and the protection action cause the loss on the person and the national wealth, more can in measuring process, can cause threat the power system stability operation.
(2) in the power station; If desired secondary side is carried out wiring; Need strictly observe a series of rules, CVT is carried out the operation of cutting load etc. and so on, some transformer station even need to wait for that the relay protection group carries out the boundary of CVT secondary side; This has just caused very big influence to the simplicity of measuring process, has increased greatly and has measured the required time.
Summary of the invention
The objective of the invention is to overcome the defective of prior art and a kind of MOA current in resistance property detection system is provided; Save the CVT secondary side wiring in the measuring process; And original single equipment is divided into two; Both pass through the GPS synchro measure time, thereby accurately obtain MOA voltage and circuital phase differential, obtain current in resistance property thereby calculate.
The technical scheme that realizes above-mentioned purpose is:
A kind of MOA current in resistance property detection system, the MOA monitor cartridge that comprises the CVT monitor cartridge that connects CVT and be connected the lightning stroke counter two ends that the MOA lower end is connected in series, said CVT monitor cartridge and the wireless connections of MOA monitor cartridge, wherein:
Said CVT monitor cartridge and MOA monitor cartridge are through the GPS synchro measure time; Said MOA monitor cartridge is measured the total current of MOA; The three-phase voltage of said CVT monitor cartridge synchronous acquisition CVT secondary output terminal calculates the instantaneous phase of three-phase voltage and sends to said MOA monitor cartridge;
Said MOA monitor cartridge combines MOA total current that records and the instantaneous phase that receives, and calculates the current in resistance property of MOA.
Above-mentioned MOA current in resistance property detection system; Wherein, Described CVT monitor cartridge comprises first microprocessor; And first amplifying circuit, a GPS (GPS) module, first wireless communication module and a Flash (Flash Memory) storer that are connected respectively with this first microprocessor, and first holding circuit that connects said first amplifying circuit, this first holding circuit connects described CVT.
Above-mentioned MOA current in resistance property detection system; Wherein, Described MOA monitor cartridge comprises second microprocessor; And second amplifying circuit, the 2nd GPS module, second wireless communication module, the 2nd Flash storer, keyboard and the display screen that are connected respectively with this second microprocessor, and second holding circuit that connects said second amplifying circuit, this second holding circuit connects the two ends of said lightning stroke counter.
The invention has the beneficial effects as follows: the present invention has saved the CVT secondary side wiring in original measuring process; Original single equipment is divided into two; One is fixedly installed in the CVT side, and another one is made mancarried device, and both are through the GPS synchro measure time; Thereby realize the measurement of MOA voltage and circuital phase differential, obtain current in resistance property thereby calculate.Simultaneously, the present invention is with low cost, has extremely strong practicality.
Description of drawings
Fig. 1 is a traditional M OA current in resistance property measuring method synoptic diagram;
Fig. 2 is the structural representation of MOA current in resistance property detection system of the present invention.
Embodiment
To combine accompanying drawing that the present invention is described further below.
See also Fig. 2, MOA current in resistance property detection system of the present invention, the MOA monitor cartridge 2 that comprises the CVT monitor cartridge 1 that connects CVT and be connected the lightning stroke counter two ends that the MOA lower end is connected in series, CVT monitor cartridge 1 and 2 wireless connections of MOA monitor cartridge, wherein:
The three-phase voltage of CVT monitor cartridge 1 monitoring CVT secondary output terminal; CVT monitor cartridge 1 is passed through the GPS synchro measure time with MOA monitor cartridge 2; When MOA monitor cartridge 2 is measured MOA circuital; CVT monitor cartridge 1 is sampled to three-phase voltage synchronously, calculates the instantaneous phase of three-phase voltage, and through wireless transmission the instantaneous phase value that obtains is transferred to MOA monitor cartridge 2; MOA monitor cartridge 2 combines MOA total current that records and the instantaneous phase that receives, and calculates the current in resistance property of MOA.
Among the present invention; CVT monitor cartridge 1 comprises first microprocessor 11; And first amplifying circuit 12 that is connected respectively with this first microprocessor 11, a GPS module 13, first wireless communication module 14 and a Flash storer 15; And first holding circuit 16 that connects first amplifying circuit 12, this first holding circuit 16 connects the secondary output terminal of CVT, wherein:
The 2nd GPS module 23 in the one GPS module 13 and the MOA monitor cartridge 2 is used for the synchro measure time jointly;
The one Flash storer 15 plays the effect of power down protection in order to the historical data of storage three-phase voltage.
MOA monitor cartridge 2 comprises second microprocessor 21; And second amplifying circuit 22 that is connected respectively with this second microprocessor 21, the 2nd GPS module 23, second wireless communication module 24, the 2nd Flash storer 25, keyboard 26 and display screen 27; And second holding circuit 28 that connects second amplifying circuit 22; This second holding circuit 28 connects the two ends of lightning stroke counter, wherein:
Second wireless communication module 24 is used for the data transmission of MOA monitor cartridge 2 and CVT monitor cartridge 1;
The 2nd Flash storer 25 is used for the historical voltage data of the measurement result and the CVT monitor cartridge 1 of store M OA total current, current in resistance property, capacity current and phase differential;
Keyboard 26 is used for the input operation instruction;
Display screen 27 shows current state and measurement result.
Among the present invention, first holding circuit 16 and second holding circuit 28 all are used for protecting device interior device and personal security, and with existing techniques in realizing, the simplest structure is a protective resistance; First amplifying circuit 12 and second amplifying circuit 22 make measurement in gamut, keep higher degree of accuracy in order to amplifying signal, and with existing techniques in realizing, the simplest structure is an amplifier; In the present embodiment, the model that the first microprocessor 11 and second microprocessor 21 are selected for use is C8051F040; The model that first wireless communication module 14 and second wireless communication module 24 are selected for use is RFC-30A.
The present invention realizes synchronously with GPS; Its principle is: when needs carry out the measurement of MOA current in resistance property; MOA monitor cartridge 2 is come interim in a PSS (umber of pulse/second) pulse; Trigger controller with its rising edge, CVT monitor cartridge 1 is sent measuring command, and begin step-by-step counting PPS from next PPS pulse.After CVT monitor cartridge 1 is received measuring command, also begin the step-by-step counting to PPS from next PPS pulse, when counting down to a predetermined value, both sides begin acquired signal respectively and calculate.
Above embodiment only supplies to explain the present invention's usefulness; But not limitation of the present invention; The technician in relevant technologies field under the situation that does not break away from the spirit and scope of the present invention, can also make various conversion or modification; Therefore all technical schemes that are equal to also should belong to category of the present invention, should be limited each claim.