CN106443224A - Lightning arrester resistive current testing sensor - Google Patents

Abstract

A lightning arrester resistive current testing sensor belongs to the field of electronic technology. The lightning arrester resistive current testing sensor comprises a single-turn straight-through current sensor circuit. The single-turn straight-trough current sensor circuit is connected with an electric power acquisition line. The single-turn straight-through current sensor circuit is provided with a bidirectional transient voltage suppressor which performs an overvoltage protection function; a resistor R1 and a resistor R6 which convert a current signal to a voltage signal and perform voltage dividing sampling; a diode D1 and a diode D2 which perform clamping on the sampled voltage; diodes D3, D4, D5, D6 which are used for performing rectification on an instantaneous lightning overvoltage; an LM358 dual operational amplifier which is used for conditioning the rectified voltage; and a CPU which counts number of action times of the lightning arrester. The lightning arrester resistive current testing sensor improves detection accuracy of an MOA lightning arrester sensor and furthermore has advantages of high interference resistance, high stability and high convenience in online detection.

Description

A kind of testing current in resistance property of lightning arrester sensor

Technical field

The present invention relates to electronic technology field, particularly to a kind of testing current in resistance property of lightning arrester sensor.

Background technology

In power system, for ensureing safe power supply, generally use in ultra-high-tension power transmission line and arrester is set comes to thunder Electricity and switching overvoltage are protected, and Zinc-Oxide Arrester (Metal Oxide SurgeArrester is called for short MOA) is from 20 generation Record since the appearance of the initial stage seventies, progressively instead of traditional Si C arrester with its excellent characteristic, widely at each electricity The electrical network of pressure grade puts into operation.

MOA has the advantage that：

1) protection feature is good

MOA has good nonlinear characteristic, presents very high resistance under normal working voltage, by its electric current only There is microampere order, close to state of insulation；When being added in the voltage above it and exceeding reference voltage, increased sharply by its electric current, Can effective over-voltage suppression, protect the safe operation of other electrical equipments.

2) robust to repeated, Motor ability is strong

MOA protection act is only released lightning current, lightning current release (being less than 100 μ s) finish, return to immediately to carry out again Secondary Motor ability, therefore MOA has continuous thunder and lightning surge protection ability, robust to repeated, Motor ability is strong.

3) through-current capability is big

The through-current capacity of MOA is determined by its valve block completely, unlike Si C arrester, is not only limited by Si C valve block between being also subject to The impact of gap arc extinguishing ability, meanwhile, the density of zinc oxide valve plate is high, and specific heat is big, the through-flow energy of general unit are Zn O valve block Big 4～4.5 times of force rate Si C.

4) volume is little, lightweight

MOA has good nonlinear characteristic without series gap because of it, the through-current capability of its unit are simultaneously Greatly, so simplifying its structure, more traditional Si C arrester height can reduce by 1/3～1/2, and quality can mitigate more than 1/3, can Save the floor space of transformer and distribution station, investment reduction.

In China, MOA is widely used in the electrical network of 3～500k V, and in terms of ruuning situation, most operations are good Good.

In order to improve the reliability that transmission line of electricity is powered, prevent Lightning Over-voltage from causing circuit breaker trip, high voltage etc. Level transmission line of electricity extensively applies Zinc-Oxide Arrester (MOA), and therefore the quality of MOA arrester performance directly affects power system peace Row for the national games.MOA arrester is connected under power frequency high voltage for a long time, can gradually form aging, is in operation it may happen that punch through damage And lose protective effect, produce extremely serious consequence, for ensureing MOA arrester safe operation, it is necessary to carry out MOA arrester Strict monitoring.

But, one does not detects more reliable MOA arrester at present.

Content of the invention

The deficiency less reliable in order to make up above MOA arrester checks means, the invention provides a kind of lightning arrester block Property testing current sensor, to solve the problem in above-mentioned background technology.

The technical scheme is that：

A kind of testing current in resistance property of lightning arrester sensor, including

Single turn core current sensor circuit, described single turn core current sensor circuit is connected to power taking circuit, single turn Punching current sensor circuit arranges two-way Transient Suppression Diode, plays overvoltage protection effect, be provided with current signal It is converted into voltage signal resistance R1, the resistance R6 of dividing potential drop sampling, be provided with the diode D1 clamped to sampling voltage and two poles Pipe D2, and for carrying out the diode D3 of rectification, diode D4, diode D5, diode D6 to instantaneous Lightning Over-voltage,

LM358 dual operational amplifier, described LM358 dual operational amplifier is in order to nurse one's health the voltage after rectification；

And CPU, described CPU is to lightning arrestor movement counting how many times.

As the technical scheme of a kind of optimization, by leakage current of an arrester sampled signal, deliver to the electric current input of A/D chip End.

As the technical scheme of a kind of optimization, by leakage current of an arrester sampled signal first through active second order bandpass filtering Obtain the third-harmonic component of sampled signal after device filtering, be then sent through the voltage input end of A/D chip.

As the technical scheme of a kind of optimization, described A/D chip is CS5460.

As the technical scheme of a kind of optimization, measurement result is carried out digital radio transmission by interface of internet of things, it is achieved Monitoring in real time.Make staff grasp at any time and advanced processing accident potential, ensure electric power network safe power supply.

As the technical scheme of a kind of optimization, digital radio transmission uses ZigBee-network to realize group-net communication.

As the technical scheme of a kind of optimization, ZigBee-network uses CC2530 chip as sensor node.

Owing to have employed technique scheme, the present invention has the advantages that：

The current detecting of MOA arrester sensor uses single turn core current sensor, it is achieved full isolation taking without residual voltage Sample loading mode, uses the current in resistance property of " triple-frequency harmonics method " measurement MOA arrester, and the advanced microprocessor technology of application enters line linearity Change processes and calculates.The present invention utilize technology of Internet of things operating MOA arrester is carried out " online, in real time, teletransmission, intelligence, Monitoring reliably ", this requires that each MOA arrester sensor becomes a node of Internet of Things, thus forms a MOA System monitored by arrester, monitors the operational factor of MOA arrester in real time, ensures safe operation of power system.

In sum, the present invention improves the correctness of MOA arrester sensor detection, and antijamming capability is strong, and stability is strong, It is easy to on-line checking.

Brief description

In order to be illustrated more clearly that the embodiment of the present invention or technical scheme of the prior art, below will be to embodiment or existing In having technology to describe, the accompanying drawing of required use is briefly described, it should be apparent that, the accompanying drawing in describing below is only this Some embodiments of invention, for those of ordinary skill in the art, on the premise of not paying creative work, also may be used To obtain other accompanying drawing according to these accompanying drawings.

Fig. 1 is the single turn core current sensor circuit schematic diagram of the present invention；

Fig. 2 is the A/D chip schematic diagram of the present invention；

Fig. 3 is the schematic diagram of the active second-order bandpass filter of the present invention.

Detailed description of the invention

Describe the present invention below in conjunction with specific embodiment.

As it is shown in figure 1, a kind of testing current in resistance property of lightning arrester sensor, including single turn core current sensor circuit, institute State single turn core current sensor circuit and be connected to power taking circuit, single turn core current sensor circuit arranges two-way transient state and presses down Diode processed, plays overvoltage protection effect, is provided with resistance R1, the electricity that current signal is converted into voltage signal dividing potential drop sampling Resistance R6, is provided with the diode D1 clamped to sampling voltage and diode D2, and for instantaneous Lightning Over-voltage is carried out whole The diode D3 of stream, diode D4, diode D5, diode D6, LM358 dual operational amplifier, the double operation amplifier of described LM358 Device in order to nursing one's health the voltage after rectification, includes inside LM358 dual operational amplifier that two independent, high-gain, interior The frequency compensated dual operational amplifier in portion, is suitable for the very wide single supply of supply voltage scope and uses, be also applied for dual power supply work Operation mode, under the condition of work recommended, source current is unrelated with supply voltage.Its range include sensor amplifier, The occasion of the use operational amplifier that DC current gain module and other all available single supplies are powered.By infrared ray sensor, letter The compositions such as number amplifying circuit, voltage comparator, delay circuit and audible alarm circuit.Infra-red detection sensor IC1 detects During the infrared signal that front human body radiation goes out, by the 2. pin faint signal of telecommunication of output of IC1, through the compositions such as triode VT1 the One-level amplifying circuit amplifies, then is input in operational amplifier IC2 carry out high-gain, low noise amplification by C2, now by IC2 1. the signal of pin output is sufficiently strong.IC3 makees voltage comparator, and its 5. pin is provided reference voltage by R10, VD1, works as IC2 1. when the signal voltage of pin output reaches the 6. pin of IC3, the voltage of two inputs compares, and now the 7. pin of IC3 is by former The high level coming becomes low level.IC4 is warning and delaying circuit, R14 and C6 forms delay circuit, and its time is about 1 minute.When When 7. pin becomes low level of IC3, C6 is discharged by VD2, and now the 2. pin of IC4 becomes low level, its 3. pin benchmark with IC4 Voltage compares, and when it is less than its reference voltage, the 1. pin of IC4 becomes high level, and VT2 turns on, and the energising of buzzer BL is sent out Go out chimes of doom.After the infrared signal of human body disappears, the 7. pin of IC3 recovers again high level output, now VD2 cut-off.Due to C6 The voltage at two ends can not suddenly change, therefore is slowly charged to C6 by R14, when the voltage at C6 two ends is higher than its reference voltage, IC4's 1. pin just becomes low level, and the time is about 1 minute, i.e. persistently within 1 minute, reports to the police.VT3, R20, C8 are formed start delay circuit, Time, its setting mainly prevented user from reporting to the police immediately after starting shooting, and allows user have time enough well also about 1 minute Leave supervision scene, when sending a telegram here again after can preventing from having a power failure, produce wrong report simultaneously.This device uses 9-12V dc source to power, by T is depressured, full-bridge U rectification, and C10 filters, and testing circuit uses IC578L06 to power.This device AC/DC, automatic non-interruption Conversion.

Also including CPU, described CPU is to lightning arrestor movement counting how many times.

Wherein X0, Y0 are leakage current of an arrester sampled signal, access in single turn core current sensor circuit.

As shown in Figures 2 and 3, in the present invention, by leakage current of an arrester sampled signal X0, Y0, the electricity of A/D chip is delivered to Stream input.First leakage current of an arrester sampled signal X0, Y0 are sampled after the filtering of active second-order bandpass filter The third-harmonic component of signal, is then sent through the voltage input end of A/D chip, and described A/D chip is CS5460.CS5460 is The single phase bidirectional power/energy measuring IC chip with serial line interface of the up-to-date release of CRYSTAL company.Exist with current Electron watt-hour meter application in widely used AD7750 and AD7755 (see《External electronic devices and components》3rd phase article in 1999) Comparing, CS5460 adds following functions：

● there is WatchDog Timer (Watch Dog Timer) and internal electric source monitor in piece；

● there is transient current, instantaneous voltage, instantaneous power, current effective value, voltage effective value, power effective value measurement And electric energy metrical function；

● provide external reset pin；

● bi-directional serial interface can be connected with microprocessor easily with internal register array；

● external clock highest frequency is up to 20MHz；

● there is power direction output instruction.

These functions increasing easily facilitate and microprocessor (MPU) interface, and can conveniently realize voltage, electric current, work( The functions such as the measurement of rate and power consumption accumulation.

In order to realize on-line real time monitoring, measurement result is carried out digital radio transmission by interface of internet of things, it is achieved real When monitoring.Make staff grasp at any time and advanced processing accident potential, ensure electric power network safe power supply.Digital radio transmission ZigBee-network is used to realize group-net communication.ZigBee-network uses CC2530 chip as sensor node.

CC2530 is to be on a real piece for 2.4-GHz IEEE 802.15.4, ZigBee and RF4CE application System (SoC) solution.It can set up powerful network node with low-down total material cost.CC2530 combines neck The premium properties of first RF transceiver, enhancement mode 8051CPU of industrywide standard, In-System Programmable flash memory, 8-KB RAM and being permitted Other powerful functions many.CC2530 has four kinds of different flash versions：CC2530F32/64/128/256, is respectively provided with 32/ The flash memory of 64/128/256KB.CC2530 has different operational modes so that it especially adapts to the system of super low-power consumption requirement. Conversion time between operational mode is short further ensure that low energy expenditure.The 8051CPU using in CC253x chip series Kernel is monocyclic 8051 compatible kernels.It has three kinds of different internal storage access bus (SFR, DATA and CODE/ XDATA), the monocycle accesses SFR, DATA and main SRAM.It also includes that a debugging interface and 18 input expandings interrupt single Unit.Interrupt control unit provide a total 18 interrupt sources, is divided into six interrupt groups, each and one of four interrupt priority levels phase Close.When equipment returns to idle pulley from activity pattern, arbitrary breakout service request is just excited.Some interruptions can also be from sleep Pattern (powering mode 1-3) wake-up device.Internal memory moderator is positioned at system centre, because it passes through SFR bus CPU and DMA Controller and physical storage and all peripheral hardwares couple together.Internal memory moderator has four internal storage access points, and accessing every time can To be mapped to one of three physical storages：One 8-KB SRAM, flash memories and XREG/SFR register.It is responsible for holding Row arbitration, and determine the order simultaneously accessing between same physical storage.8-KB SRAM be mapped to DATA memory space and Part XDATA memory space.8-KB SRAM is the SRAM of a super low-power consumption, though numerical portion power down (powering mode 2 He 3) its content can also be retained.This is a function critically important for low-power consumption application.32/64/128/256KB flash block Provide the non-volatile program memory of interior circuit programmable for equipment, be mapped to XDATA memory space.Except save routine Beyond code and constant, nonvolatile memory allows application program to preserve the data that must retain, after such equipment is restarted These data can be used.Use this function, for example, can utilize the concrete data of saved network, avoid the need for through Start completely, network is found and adition process.

Clock and power management

Digital core and peripheral hardware are powered by the low poor voltage-stablizer of 1.8-V.It provide power management function, it is possible to achieve Use the low power operation of the long battery life of different powering mode.Five kinds of different reset source are had to carry out homing device.

Peripheral hardware

CC2530 includes many different peripheral hardwares, it is allowed to the advanced application of application designer exploitation.Debugging interface is held The proprietary two-wire serial interface of row one, is used for interior circuit debugging.By this debugging interface, whole flash memory storage can be performed Which oscillator the erasing of device, control enable, stop and starting performing user program, perform instruction that 8051 kernels provide, set Put code breakpoint, and the single-step debug all instructing in kernel.Use these technology, the tune of interior circuit can be performed well Examination and the programming of external flash.

Equipment contains flash memories to store program code.Flash memories can pass through user software and debugging interface is compiled Journey.Flash controller processes write and erasing embedded flash memory memory.Flash controller allows page erasing and 4 bytes to compile Journey.

All general purpose I/O pin is responsible for by I/O controller.CPU can configure peripheral module whether control certain pin or it Whether under software control, if it does, each pin configuration is an input or output, if connect in liner Individual pullup or pulldown resistance.CPU interrupts enabling on each pin respectively.Each peripheral hardware being connected to I/O pin is permissible Select between two different I/O Pin locations, to guarantee the flexibility in different application.

System can use a multi-functional Five-channel dma controller, uses XDATA memory space to access memory, Therefore, it is possible to access all physical storages.Each passage (trigger, priority, transmission mode, addressing mode, source and target Pointer and transmission counting) configure Anywhere at memory with dma descriptor.Many hardware adaptor (AES kernel, flash memory control Device, USART, timer, ADC interface) between SFR or XREG address and flash memory/SRAM, enter line number by using dma controller According to transmission, it is thus achieved that high efficiency manipulation.Timer 1 is 16 bit timing devices, has timer/PWM function.It has one can compile The frequency divider of journey, 16 bit period values, and five respective programmable counter/capture passages, each with one 16 Fiducial value.Each counter/capture passage can serve as the sequential at a PWM output or capture input signal edge.It also may be used Producing pattern with configuration at IR, calculating timer 3 cycle, output is ANDed, and the output of timer 3 is interactive with minimum CPU Produce the consumption-orientation IR signal of modulation.

MAC timer (timer 2) is exclusively for the agreement supporting other time slots in IEEE 802.15.4MAC or software Design.Timer has a configurable timer period and 8 spilling counters, may be used for holding and follows the tracks of warp The periodicity crossed.One 16 capture register is also used for recording and receives/send the precise time that a frame starts to define symbol, or The precise time of the end of transmission, also one 16 output comparand registers can produce different gating command in the concrete time (start RX, start TX, etc.) arrive wireless module.Timer 3 and timer 4 are 8 bit timing devices, have timer/counter/ PWM function.They have a programmable frequency divider, the periodic quantity of 8, a programmable counter passage, have The fiducial value of one 8.Each counter passage can serve as a PWM output.

Sleep timer is the timer of a super low-power consumption, calculates the week of 32-kHz crystal oscillator or 32-kHz RC oscillator Phase.Sleep timer constantly runs under all working pattern except powering mode 3.Typical case's application of this timer is to make For real-time counter, or wake up timer up as one and jump out powering mode 1 or 2.

ADC supports the resolution ratio of 7 to 12, the bandwidth at 30kHz or 4kHz respectively.DC and audio frequency conversion can use height Reach eight input channels (port 0).Input may select for single-ended or difference.Reference voltage can be builtin voltage, AVDD Or a single-ended or difference external signal.ADC also has a TEMP input channel.ADC can perform periodically to take out automatically Sample or the program of ALT-CH alternate channel sequence.

Randomizer uses 16 LFSR to produce pseudo random number, and this can be read or ordered by gating by CPU Processor is made directly to use.Such as random number can serve as producing random key, is used for safety.

AES encryption/deciphering kernel allows user to use the aes algorithm encrypting and decrypting data with 128 keys.This Kernel can support the AES operation that IEEE 802.15.4MAC safety, ZigBee-network layer and application layer require.

One built-in house dog allows CC2530 to reset self in the case that firmware is hung up.When WatchDog Timer by Software enables, and it must periodically be removed；Otherwise, equipment is reset upon when its time-out resets upon it.Or it can be configured for use as one Individual general 32-kHz timer.

USART 0 and USART 1 each be configured to that SPI is master/slave or a UART.They provide for RX and TX Double buffering, and hardware flow control, be therefore very suitable for the full duplex applications of high-throughput.High accuracy each with oneself Baud rate generator, therefore can make general timer free out as other purposes.

Wireless device

CC2530 has the compatible wireless transceiver of an IEEE 802.15.4.Nuclear control simulation wireless module in RF.Separately Outward, it providing an interface between MCU and wireless device, this allows to send order, reading state, be automatically brought into operation and Determine the order of wireless device event.Wireless device also includes a Packet Filtering and Address Recognition module.

The above is only the better embodiment of the present invention, thus all according to the construction described in present patent application scope, The equivalence that feature and principle are done changes or modifies, in the range of being all included in present patent application.

Claims (7)

1. a testing current in resistance property of lightning arrester sensor, it is characterised in that：Including

Single turn core current sensor circuit, described single turn core current sensor circuit is connected to power taking circuit, single turn core Current sensor circuit arranges two-way Transient Suppression Diode, plays overvoltage protection effect, be provided with and current signal is changed Become voltage signal resistance R1, the resistance R6 of dividing potential drop sampling, be provided with the diode D1 clamped to sampling voltage and diode D2, And for carrying out the diode D3 of rectification, diode D4, diode D5, diode D6 to instantaneous Lightning Over-voltage,

LM358 dual operational amplifier, described LM358 dual operational amplifier is in order to nurse one's health the voltage after rectification；

And CPU, described CPU is to lightning arrestor movement counting how many times.

2. a kind of testing current in resistance property of lightning arrester sensor as claimed in claim 1, it is characterised in that：By arrester leakage electricity Stream sampled signal, delivers to the current input terminal of A/D chip.

3. a kind of testing current in resistance property of lightning arrester sensor as claimed in claim 2, it is characterised in that：By arrester leakage electricity First stream sampled signal obtains the third-harmonic component of sampled signal after the filtering of active second-order bandpass filter, is then sent through AD core The voltage input end of piece.

4. a kind of testing current in resistance property of lightning arrester sensor as claimed in claim 3, it is characterised in that：Described A/D chip is CS5460.

5. a kind of testing current in resistance property of lightning arrester sensor as described in any one of claim 1-4, it is characterised in that：Will measurement Result carries out digital radio transmission by interface of internet of things, it is achieved monitor in real time.

6. a kind of testing current in resistance property of lightning arrester sensor as claimed in claim 5, it is characterised in that：Digital radio transmission is adopted Realize group-net communication with ZigBee-network.

7. a kind of testing current in resistance property of lightning arrester sensor as claimed in claim 6, it is characterised in that：ZigBee-network uses CC2530 chip is as sensor node.