CN207164187U

CN207164187U - Digital AC line insulation monitor

Info

Publication number: CN207164187U
Application number: CN201721171206.6U
Authority: CN
Inventors: 苑芳; 宋大卫
Original assignee: Shandong Navigation Electrical Equipment Co Ltd
Current assignee: Shandong Navigation Electrical Equipment Co Ltd
Priority date: 2017-09-13
Filing date: 2017-09-13
Publication date: 2018-03-30
Anticipated expiration: 2027-09-13

Abstract

The utility model discloses digital AC line insulation monitor, solves the problems, such as that spot ship AC network insulating monitoring precision and reliability are low.It includes N number of current transformer, N number of low pass filter, a/d converter, switching value MIM message input module, switching value message output module, the first photo-coupler, the second photo-coupler, information monitoring main frame and PC computers；N number of current transformer is arranged on each short-circuiting device of load screen, and the high low value of each branch road line insulation of detection is communicated after corresponding low pass filter is transmitted to a/d converter and changed through CAN and Ethernet interface with information monitoring main frame or PC computers.Its current transformer detects fault current, and fault current is carried out into correlation computations processing and logic judgment, and judged result is communicated to operator on duty by information monitoring main frame or PC computers, understands line insulation trouble point in time.The utility model insulating monitoring precision is high, improves power network power supply reliability.

Description

Digital AC line insulation monitor

Technical field

The utility model belongs to fault test set technical field, especially a kind of digital AC line insulation monitoring Instrument.

Background technology

Modern ships power system generally use phase three-wire three insulation system, it is long-term sudden and violent because long-term running environment is severe Expose outside, influenceed by environmental factors such as sunlight, stormy waves, greasy dirt, seawater and moulds so that network of ship decreasing insulating, Line insulation failure happens occasionally, and gently then causes electrical equipment to damage, heavy then cause Ship Electrical Power System short-circuit fire, or even heavy The major accident such as ship or casualties.Therefore, how effectively to search network of ship insulation fault turns into marine vessel power technical staff One of research contents.

And when insulation reduction failure occurs for the AC network of ship, faulty line is found out as early as possible and recovery system is normally transported OK, it is the task of top priority, but power system network is distributed in each position of ship, and lookup fail operation amount is huge, wastes time and energy, The normal operation of ship is influenceed, therefore a precision of design is high, the high insulating monitor to ship AC network of reliability is ten Divide necessary.

The content of the invention

In order to overcome the problem of precision of spot ship AC network insulating monitoring is low, workload is big low with reliability, this The purpose of utility model is to provide the digital AC line insulation monitor that a kind of monitoring accuracy is high, reliability is good.

Technical scheme is used by the utility model solves its technical problem：Digital AC line insulation monitor, Including N number of current transformer, N number of low pass filter, a/d converter, switching value MIM message input module, switching value information output mould Block, the first photo-coupler, the second photo-coupler, information monitoring main frame and PC computers, wherein, N is just whole more than or equal to 2 Number, the number of described low pass filter and the number of current transformer correspond；N number of current transformer is arranged on negative On each short-circuiting device for carrying screen, and low pass filter corresponding to the high low value warp of each branch road line insulation of detection is transmitted to AD Converter, after a/d converter is changed, led to through CAN and Ethernet interface with information monitoring main frame or PC computers Letter；The switching value MIM message input module is connected with the first photo-coupler, the switching value message output module and the second optocoupler Clutch connects, first photo-coupler and the second photo-coupler through CAN and Ethernet interface and information monitoring main frame or PC computers are communicated；Described switching value MIM message input module is used to carry out each way switch amount input signal isolation turn Change；Described switching value message output module is used for external output quantity.

Wherein it is preferred to the low pass filter uses second order all-pass filter.

Wherein it is preferred to the a/d converter uses AD7686 analog-digital converters.

Wherein it is preferred to first photo-coupler and the second photo-coupler use high-speed light coupling isolator 6N137。

Wherein it is preferred to described information monitoring host computer is connected with touching display screen, to show current state information, Fault message and warning information and by operate touching display screen send instruction, with complete control perform, data acquisition.

Wherein it is preferred to the switching value MIM message input module and switching value message output module use module plug Pattern.

Compared with prior art, the beneficial effects of the utility model are as follows：

The utility model is to detect fault current using current transformer, will be carried out by the fault current of detection related Processing and logic judgment are calculated, judged result is communicated to operator on duty, CAN by information monitoring main frame or PC computers With high bit rate, high electromagnetism interference, low cost and high bus utilization, the steady of monitoring system intercommunication ensure that It is fixed, reliable and quick, save substantial amounts of manpower and materials.The precision of the utility model insulating monitoring is high, and improving power network power supply can By property.

Brief description of the drawings

The utility model is described further with reference to the accompanying drawings and examples.

Fig. 1 is a kind of principle assumption diagram of the present utility model；

Fig. 2 be switching value MIM message input module of the present utility model, switching value message output module, the first photo-coupler, The interface connection figure of second photo-coupler and CAN；

Fig. 3 is the circuit connection diagram of low pass filter of the present utility model.

Marked in figure：1. current transformer, 2. low pass filters, 3.AD converters, 4. switching value MIM message input modules, 5. Switching value message output module, 6. first photo-couplers, 7. second photo-couplers, 8.CAN buses, 9. Ethernet interfaces, 10. letters Cease monitoring host computer, 11.PC computers, 12. touching display screens.

Embodiment

In Fig. 1, a kind of digital AC line insulation monitor, including N number of current transformer 1, N number of low pass filter 2nd, a/d converter 3, switching value MIM message input module 4, switching value message output module 5, the first photo-coupler 6, the second optical coupling Device 7, information monitoring main frame 10 and PC computers 11.Wherein, N is the positive integer more than or equal to 2.The number of low pass filter 2 with The number of current transformer 1 corresponds.

As shown in figure 1, N number of current transformer 1 is arranged on each short-circuiting device of load screen, N number of current transformer 1 will be examined Low pass filter 2 corresponding to the high low value warp for each branch road line insulation surveyed is transmitted to a/d converter 3, is changed through a/d converter 3 Afterwards, communicated through CAN 8 and Ethernet interface 9 with information monitoring main frame 10 or PC computers 11.Electricity of the present utility model Current transformer detects fault current, correlation computations processing and logic judgment will be carried out by the fault current of detection, judgement As a result operator on duty is communicated to by information monitoring main frame or PC computers.

A/d converter 3 of the present utility model uses AD7686 analog-digital converters, the electric current that N number of current transformer 1 is gathered Signal is converted into data signal；CAN has high bit rate, high electromagnetism interference, low cost and high bus utilization, The stabilization, reliable and quick of monitoring system intercommunication is ensure that, saves substantial amounts of manpower and materials.

Low pass filter 2 of the present utility model filters out high-frequency noise and anti-aliased.As shown in figure 3, low pass filter 2 uses Second order all-pass filter, it inputs the current signal of collection to resistance R2 one end, the other end and the electricity of the resistance R2 Hold C2 one end connection, electric capacity the C2 other end and comparator U1：A inverting input connection, resistance the R2 other end and electricity Hold C1 one end connection, resistance the C1 other end and comparator U1：A output end connection, electric capacity the C2 other end and resistance R1 One end connection, the resistance R1 other end and comparator U1：A output end connection, resistance R2 one end and resistance R3 one end Connection, resistance the R3 other end and comparator U1：A in-phase input end connection, the comparator U1：A in-phase input end warp Resistance R4 is grounded GND, comparator U1：A output end output digit signals, its phase shift performance are good, it is contemplated that the power frequency of electric current and It is good with preferable sensitivity, the linearity nearby and all-pass filter is in quality factor Q=1.

In Fig. 1, switching value MIM message input module 4 is connected with the first photo-coupler 6, switching value message output module 5 with Second photo-coupler 7 connects；In Fig. 1, Fig. 2, the first photo-coupler 6 and the second photo-coupler 7 are through CAN 8 and Ethernet Interface 9 is communicated with information monitoring main frame 10 or PC computers 11.Wherein, switching value MIM message input module 4 and switching value letter Breath output module 5 uses module plug pattern, and switching value MIM message input module 4 is used for each way switch amount input signal Carry out isolation conversion；Switching value message output module 5 is to be used for external output quantity.

In the present embodiment, the input signal of switching value MIM message input module 4 includes：Systematic reset signal, auto-manual Control signal, manual control signal and switch changed position signal.It is normal that the output signal of switching value message output module 5 includes DSP Run indication signal, ARM normal operations indication signal, the normal indication signal of communication, self test failure indication signal, the operation of injection source Indication signal, electric network fault phase alarm signal, line insulation failure alarm signal and distant signal reset signal.

In order to increase the antijamming capability of each control node, crosstalk between circuit is prevented, as shown in Fig. 2 the first optical coupling The photo-coupler 7 of device 6 and second uses high-speed light coupling isolator 6N137.

It should be further stated that directly observe and operate in order to facilitate staff, in Fig. 1, information monitoring master Machine 10 is connected with a touching display screen 12, for showing current state information, fault message and warning information；Staff Instruction is sent by operating touching display screen 12, is performed with completing control, data acquisition.

After the low-pass filtered device 2 of signal that current transformer 1 of the present utility model gathers filters, then pass through through a/d converter 3 Analog signal is converted into data signal, and by the data transfer of CAN 8, information monitoring main frame 10 is analyzed, and operator on duty is with regard to energy Recognize line insulation trouble point and fix a breakdown in time, without power-off in whole process, improve the reliability that power network is powered, Failure artificially need not be being investigated one by one, save manpower and materials.

While there has been shown and described that embodiment of the present utility model, for the ordinary skill in the art, It is appreciated that these embodiments can be carried out with a variety of changes in the case where not departing from principle of the present utility model and spirit, repaiied Change, replace and modification, the scope of the utility model are defined by the appended claims and the equivalents thereof.

Claims

1. digital AC line insulation monitor, including N number of current transformer, N number of low pass filter, a/d converter, switch Measure MIM message input module, switching value message output module, the first photo-coupler, the second photo-coupler, information monitoring main frame and PC Computer, wherein, N is the positive integer more than or equal to 2, and the number of described low pass filter and the number of current transformer are one by one It is corresponding；N number of current transformer is arranged on each short-circuiting device of load screen, and by the height of each branch road line insulation of detection Low pass filter corresponding to low value warp is transmitted to a/d converter, after a/d converter is changed, through CAN and Ethernet interface with Information monitoring main frame or PC computers are communicated；The switching value MIM message input module is connected with the first photo-coupler, described Switching value message output module is connected with the second photo-coupler, and first photo-coupler and the second photo-coupler are through CAN Communicated with Ethernet interface with information monitoring main frame or PC computers；Described switching value MIM message input module is used for each Way switch amount input signal carries out isolation conversion；Described switching value message output module is used for external output quantity.

2. digital AC line insulation monitor according to claim 1, it is characterised in that：The low pass filter is adopted With second order all-pass filter.

3. digital AC line insulation monitor according to claim 1, it is characterised in that：The a/d converter uses AD7686 analog-digital converters.

4. digital AC line insulation monitor according to claim 1, it is characterised in that：First photo-coupler High-speed light coupling isolator 6N137 is used with the second photo-coupler.

5. digital AC line insulation monitor according to claim 1, it is characterised in that：Described information monitoring host computer It is connected with a touching display screen, to show current state information, fault message and warning information and be touched by operating Formula display screen sends instruction, is performed with completing control, data acquisition.

6. digital AC line insulation monitor according to claim 1, it is characterised in that：The switching value information is defeated Enter module and switching value message output module and use module plug pattern.