The quality of power supply (power quality) characterizes the quality level of Utilities Electric Co.'s power supply, also is the reflection of power consumer electricity consumption quality, is the important indicator of weighing the electrical power services level in the electricity market evolution.Along with development of electronic technology, on the one hand, nonlinear device and equipment obtain application more and more widely, and waveform distortion of the power supply network is more and more serious, and harmonic wave (wave form distortion) content also significantly increases; On the other hand, along with various complexity, precision, constantly universal to the consumer of quality of power supply sensitivity, people improve constantly the requirement of the quality of power supply.Power quality problem in the electric system can be divided into stable state and transient state two big classes.The stable state power quality problem is a principal character with the wave form distortion, and the duration is longer, can be divided into following several types again: harmonic wave, a harmonic wave, Voltage unbalance, superpotential and under-voltage.The transient power quality problem is a feature with frequency spectrum and duration weak point normally, comprises pulse transient state and vibration transient state two classes, and its form of expression has: voltage transient, voltage flicker, voltage swells, rapid drawdown, short supply interruption.
Electric energy quality monitoring is an important means of finding power quality problem, can be used for determining the reason of electric power system fault.Equipment for monitoring power quality is by monitoring voltage, the electric current mass parameter of electrical network (grid side or load are surveyed) in real time, to realize the assessment to monitoring point quality of power supply level.Because be subjected to the data storage quantitative limitation, at present commercially available equipment for monitoring power quality all needs to be provided with activation threshold value, only monitor data variation surpass threshold value just can record; The easy like this omission that causes effective information is difficult to synthetically investigate the quality of power supply comprehensively.In addition, cycle sampling rate problem also is the technical barrier of electric energy quality monitoring, and the cycle sampling rate is low, usually causes losing of short transient power information of frequency spectrum and duration.
The utility model content
Technical problem to be solved in the utility model provides a kind of electric energy quality monitoring analytical equipment, and this device can comprehensive detection, record and the analysis quality of power supply, determines the electric power system fault reason.Specifically, this device is not provided with threshold value aspect data recording, thereby has avoided the omission problem of quality of power supply information; This device adopts wave height sampling rate weekly, thereby has avoided losing of transient power quality information; A plurality of these devices can also be in big regional inter-sync operation.
For solving the problems of the technologies described above, the utility model electric energy quality monitoring analytical equipment comprises monitoring terminal machine and display, and described monitoring terminal machine is connected with three-phase circuit by the mutual inductor module, is connected with display by data line again; Wherein, monitoring terminal comprises:
The mutual inductor module comprises that it is that light current is pressed the voltage of signals mutual inductor and is the current transformer of weak current signal with the heavy current conversion of signals on the three-phase line that the forceful electric power of three-phase line is pressed conversion of signals;
Analog-to-digital conversion module with analog to digital conversion passage of multidiameter delay is that digital signal is passed to the DSP sampling module again with the light current pressure of mutual inductor module transmission, the analog signal conversion of weak current;
The cycle sampling rate is connected with analog-to-digital conversion module at the DSP sampling module more than 512 o'clock, and the digital signal of analog-to-digital conversion module input is carried out continuous sampling, and the data information transfer that collects is compressed memory module to CPU;
CPU compresses memory module, and the data of DSP sampling module transmission are directly compressed, and the data after the compression are stored or outwards sent by communication module;
Communication module comprises local communication port, wired network interface and/or radio network interface;
Power module links to each other with analog-to-digital conversion module, DSP sampling module, CPU compression memory module, communication module, comprises AC AC power, DC direct supply, reserve battery power supply.
As further improvement of the utility model, the real-time clock of the also built-in precision of described DSP sampling module more than 0.1ms keeps calibration by communication module and Utilities Electric Co. clock source.
In the utility model quality of power supply management devices, the cycle sampling rate can not omitted any transient power quality problem at the DSP sampling module more than 512 o'clock, CPU compression memory module is directly compressed the data of DSP sampling module transmission, any threshold value, trigger value are not set, realize continuous recording.The all right built-in real-time clock of described DSP sampling module is guaranteed the time synchronized of the interior a plurality of quality of power supply management devices in zone greatly.
See also Fig. 1, the utility model electric energy quality monitoring analytical equipment comprises monitoring terminal and display, and described monitoring terminal is connected with three-phase circuit by the mutual inductor module, is connected with display by Ethernet cable again; Wherein, monitoring terminal comprises:
The mutual inductor module comprises that it is that light current is pressed voltage of signals mutual inductor (PT) and is the current transformer (CT) of weak current signal with the heavy current conversion of signals on the three-phase line that the forceful electric power of three-phase line is pressed conversion of signals.
Analog-to-digital conversion module with 6 road analog to digital conversion passages that walk abreast is that digital signal is passed to the DSP sampling module again with the light current pressure of mutual inductor module transmission, the analog signal conversion of weak current; All analog to digital conversion passages of described analog-to-digital conversion module are sampled simultaneously, do not need to exchange calculating between each passage (as current channel, voltage channel, temperature channel etc.), thereby have optimized result of calculation; Each input channel all comprises normal range and two ranges of full scale.
The cycle sampling rate is connected with analog-to-digital conversion module at the DSP sampling module more than 512 o'clock, and the digital signal of analog-to-digital conversion module input is carried out all data continuous sampling, and the data information transfer that collects is compressed memory module to CPU.Described DSP sampling module adopts the real-time flicker measurement of high precision 16 000V/75A, and gamut reads, and can realize weekly the continuous sampling function of 512 data of ripple, and writes down transient electric-energy quality informations such as detailed voltage fluctuation, flickering, a harmonic wave.
CPU compresses memory module, and DSP sampling module and load module data are compressed, and adopts the high compression ratio data compression technique, has realized 500: 1 compressibility, can store the total data of 20ms grid cyclic wave more than a year continuously.Data storage after the compression or outwards transmit by communication module for example passes to display by Ethernet cable.After the compression storage was finished, operational analysis software can can't harm true curve, harmonic wave histogram and the written record of the power waveform in arbitrary moment of reduction.
Communication module comprises local communication port, wired network interface and/or radio network interface; Local communication port comprises RS232 interface, RS485 interface, RS422 interface, USB interface etc.; Wired network interface comprises the Ethernet cable port; Radio network interface comprises various public radio communication network ports such as GSM, GPRS, CDMA, WCDMA, CDMA2000, TD-SCDMA.
Power module and analog-to-digital conversion module, DSP sampling module, CPU compression memory module, communication module link to each other, comprise the AC AC power (100-240V, 50Hz), DC direct supply (48V ± 10%) and internal cell power supply.
Described display is independent mutually with monitoring terminal, adopts LCD usually.Monitoring terminal connects display by Ethernet cable, and this Ethernet cable realizes that simultaneously electric energy (48V direct current) transmits and the signal transmission.Display separates with main frame, has made things convenient for that the related personnel consults, management information, and need not to open chamber door contact monitoring terminal can long-range reading display.Described display can also be a touch-screen display, and the staff can revise correlation parameter by touch-screen.
Can also comprise computing machine in the above-mentioned electric energy quality monitoring analytical equipment, adopt portable computer usually.When a plurality of electric energy quality monitoring analytical equipments are disposed simultaneously, can attach and dispose one or more computing machine, every computing machine connects one or more electric energy quality monitoring analytical equipments by wired or wireless network, and each electric energy quality monitoring analytical equipment also connects one or more computing machine by wired or wireless network.Described wired or wireless network comprises proprietary net, also comprises common network, as internet, TD-SCDMA network etc.Can built-in electric energy quality monitoring analysis software in the computing machine, thus obtain, show, manage and analyze the electric network data of any monitoring terminal at any time.For example monitor the network operation state in real time, generate the customized form of client etc. with Email or comprehensive quality of power supply report and fault alarm, the automatic or manual of short message transmission.
Can also comprise load module in the above-mentioned monitoring terminal, this module is monitored the status information of power information, switchgear, protective relay, isolating switch by remote measurement and remote signalling means.The data transfer that this module collects to CPU compression memory module is compressed.
In the above-mentioned CPU compression memory module, the data after the compression can also pass to any computing machine or Utilities Electric Co. dispatching center etc. by communication module.
All right built-in high precision (precision is more than the 0.1ms) real-time clock of above-mentioned DSP sampling module keeps calibration with communication module and Utilities Electric Co. clock source.When a plurality of electric energy quality monitoring analytical equipments operate the big regional power grid circuit of monitoring simultaneously, just can guarantee the time synchronized of all electric energy quality monitoring analytical equipments.
See also Fig. 2, this is the deployment synoptic diagram of the utility model electric energy quality monitoring analytical equipment.In the preferred case, data after the CPU compression memory module of each electric energy quality monitoring analytical equipment will be compressed are sent to special data analysis storage center by the Ethernet cable port or the wireless network port of communication module, managerial personnel or user according to different rights by this data storage center of wired or wireless access to netwoks, thereby obtain the quality of power supply situation of respective lines.
The quality of power supply can synthetically be monitored, be write down, analyze to the utility model electric energy quality monitoring analytical equipment, to determine the electric power system fault reason.This utility model has overcome effective information record disappearance, and drawbacks such as transient information omission have realized all data uninterrupted recording.The utility model also solved quality of power supply terminal Monitoring and Controlling simultaneously, the problem of poor synchronization.When many electric energy quality monitoring analytical equipments are disposed, can guarantee time synchronized with Utilities Electric Co. by built-in real-time clock, and write down the continuous parameters of electric power of all measurement points, form region-wide electric energy quality monitoring.The utility model also is particularly suitable for being installed in unattended place, and does not need to lay specially communication line, only relies on existing public radio communication network to get final product.