2013年8月29日星期四

AC and DC optical current transformer data acquisition system has great similarity

AC and DC current transformer optical data acquisition system has great similarities Circuit breaker  the nature of the signal and the system requirements are different between the two, there are some differences in the design, the main control mode is the sampling and conversion the results of treatment methods, which were compared. From the theoretical analysis of the key exchange data  electric transformer  system design, from design performance requirements, detailing the design principles and methods, and the results used to deal with the root mean square error of air circuit breaker  analysis of algorithms. Data acquisition system performance of many, this article focuses on the dynamic performance evaluation method, and in accordance with the method of the exchange of data acquisition system dynamic performance tests.

Optical Current Transformer Data Acquisition System

Further study of the high-voltage AC and DC current digital measurement methods, and combined with the subject requirements, the design of the optical current transformer data acquisition system.  air circuit breaker  transformers to IEC standards as a starting point to compare the active photoelectric current transformers are several possible  Voltage stabilizer , the final choice based on a successive  mcb circuit breaker  analog-to-digital conversion of the digital measurement method for measuring accuracy, system extension sometimes small. Further, given the principle of active optical current transformer block diagram of the system is analyzed in detail the composition and function of each part, defined as the research object data acquisition system structure.

Developed electronic current transformer related standards

Production and living the high demand for power on the power system safe, reliable and economic operation put forward higher requirements, the traditional current  mcb circuit breaker  power system can not meet the development needs of current measurement for power  electric transformer  new technologies and new method has become imperative. To this end, the International Electrotechnical Commission (IEC) has developed an electronic current transformer related standards, current  air circuit breaker  for the new development has laid a good foundation. Active optical current transformer is electronic current transformer is an important direction of development, at home and abroad has been a lot of research work carried out and made ​​practical many valuable experience.

Standard electronic transformer itself features include interface functions

In order not to restrict the development of CT technology, the standard for electronic transformer itself features include interface functions to achieve is not specified, it just describes a function of externally visible functions and consistency requirements. Electronic transformer with conventional electromagnetic transformer is one of the biggest difference is that the  Air circuit breaker  to provide direct digital signal, it is this difference, the substation automation system will produce a comprehensive and far-reaching impact. Electronic  mcb circuit breaker  protection devices and metering rational interface design can not only simplify the secondary equipment, and can improve overall system accuracy and reliability. It also promotes the standardization of interfaces substation automation communication control system optimization, and ultimately to achieve information sharing within the substation and system integration. First introduced digital outputs combined unit, and electronic transformer digital interface communication model. Analysis based on the standard IEC61850 substation automation integration programs, and through the process of the substation communication layer and the spacer layer specification study discusses the application of electronic  electric meter substation automation system topology obtained phased improvements. On Electronic Transformer Digital Output Characteristics doing elaborated after a set according to IEC standard digital interface solutions, and developed based on IEC61850 standard digital interfaces. Finally, Electronic Transformer digital interface with the verification, the experimental results show that the digital interface developed to meet the substation automation system communication functions for stability and real-time requirements, to meet the standard IEC60044-8 error vs. 0.2 level electronic instrument transformers limited accuracy requirements, can be applied to 0.2 electronic transformer digital output.

Transformer and substation secondary equipment

In order to apply electronic transformer substation automation system, one of the key issues to be resolved is the transformer substation secondary equipment with the interface between. Electronic  Circuit breaker  secondary output is divided into two kinds of digital and analogue outputs. Analog output is to use existing analog interface  Air circuit breaker  secondary equipment, is a transitional measure. The digital output is a new electronic transformer substation on request. International  electric meter  Commission developed a standard file electronic transformer IEC60044-7/8, which includes parts of the interface described.

Multi-channel electronic transformer data reception and decimation filtering

Process level digital signal processing module's function is to complete the multi-channel electronic transformer data reception and decimation filtering, the paper discusses a follow IEC60044-8 standard combined unit to achieve synchronization of the new method to analyze the implementation of efficient decimation  Voltage stabilizer , using VHDL language programming and applied to the FPGA, FPGA high integration, flexible programming features, ensure the system's real-time and  electric meter . In the process layer coding module, in accordance with the requirements of the standard IEC60044-8 data after adding the extracted header, CRC checksum complete set of frames, then the complete data frame Manchester encoded  Air circuit breaker  the fiber to the spacer layer, the paper encoding module circuits were designed in detail and compared. The spacer layer, based on all-digital phase-locked loop technology, using Manchester code itself has a wealth of information bit timing characteristics of the design of the decoding circuit module, the realization of high-speed data stream reception and a synchronous clock signal extracted from the data decoding, and finally split frame check.

New digital electronic transformer

With the development of the power system, the traditional electromagnetic transformer has been unable to satisfy practical needs. New digital electronic transformer due to the introduction of optical fiber transmission, the new signal processing unit and a digital  electric meter , with insulation structure is simple and reliable, small size, high accuracy, and other equipment interface is compatible with other significant advantages, which gradually gained wide acceptance and  circuit breakers  . Paper, based on the principle of electromagnetic induction coil electronic  Electric transformer  (ECT) and the partial implementation of the design method to analyze the combined unit and laser for energy and other major part of the implementation plan. Type test results show that the prototype. The system is fully up 0.2 accuracy metrics and comply with the latest standards IEC61850 requirements.

Voltage transformer errors on the impact of distance protection

Current and voltage transformer error on the impact of distance protection, indicating current and voltage transformer protective impedance error will cause the distance  air circuit breaker  accuracy decreased, resulting in shortening of protected areas and other issues. On this basis, summed up the traditional solution saturation current transformer errors and basic methods, such as increasing the transformer ratio, reducing the current transformer secondary load, using the phase comparison principle, increasing the data windows. However, due to the traditional  electric meter  current transformer inherent defects, it is difficult to eradicate from the principle of protection of its lines caused problems. With the computer, optical fiber technology, emerging electronic current transformer is a set of electronics and optical technology as one of the new optical  Air circuit breaker , its precision, high reliability, wide bandwidth, non-magnetic saturation, anti-interference ability and other characteristics, the decision that it will gradually become the traditional electromagnetic current transformer alternatives. Therefore, this paper presents the use of electronic current transformers as a distance measuring element protection proposals demonstrated using optical current transformer on Distance Protection starter components, phase selector, impedance components and other functional elements also brings advantages. Analysis showed that the electronic current transformers distance protection will greatly enhance the accuracy and operation of each component reliability.

Sensor output signal acquisition and processing of

Active Electronic Current Transformer with Rogowski coil, coil, etc., as a low-power sensors, the need to use  air circuit breaker  side analog to digital converter module (ie remote module) to a sensor output signal acquisition and processing, and the Far end module must have the appropriate power supply, power supply designed for this  electric meter  and reliable work to become active electronic current transformer promote the application of a key.

Electromagnetic current transformer measuring and monitoring large current

For the current power system using electromagnetic current transformer measuring and monitoring of the existence of a large current issues related to study design of a fiber-optic  mcb circuit breaker  pressure differential current sensor. Based on Faraday effect and hybrid fiber current sensor research program compared to the high-pressure side of the system to take away the power and resolve optical properties affected by  electric meter  serious difficulties. Transformation of high current through the coil wound on the amount of voltage to modulate the piezoelectric ceramic fiber optical  electri cenergy meter  detected by the differential phase variation amount. Simple structure, large dynamic range, on the outside slow variables (such as temperature) is not sensitive to impact.

Transformer on-site testing requirements

With the transmission system voltage levels and transmission capacity to continuously improve, transformers undergone significant changes, the original test methods can not meet the requirements of transformer on-site testing. Comprehensive  mcb circuit breaker  for  Circuit breaker  testing technology field test methods, test model, test equipment and related standards and norms and other aspects of the situation and the level of development of a comprehensive introduction and exposition electric transformer  out that integrated transformer characteristic test technology development status unable to meet the needs of development and application of transformers, it is necessary in this area as the relevant technology methods and tools, test equipment and instruments for further in-depth study.

Voltage transformer is the power system energy metering

Power system voltage transformer power measurement, voltage measurement and relay protection and other essential electrical equipment. At present, the application of the more common is the electromagnetic voltage  electric transformer  and capacitor voltage transformers. The two voltage transformers in the design process involves a large number of  electric meter , insulation and other calculations. The traditional method of voltage transformer design efficiency is not high, the product development cycle is longer.

Current transformer is a very useful electrical equipment

Current transformers are electrical devices useful because it can be converted to high AC current can be easily controlled, low current. The current  Electric transformer  winding, the secondary winding, the core and the insulator composition, if the bus without a transformer, the  circuit breakers  the manufacturing process for the first time there is no winding. In contrast, in each susceptor through the conductor or bus may be configured as a primary winding.
Current  air circuit breaker  according to IEC44-1 production, and the secondary terminals below the transparent protective cover. Measuring voltage and current transformers are two types of protection.

Zero sequence current protection zero sequence CT installation process to comply with the relevant standards

For the zero-sequence current protection zero sequence CT installation process must comply with the relevant standards. For IT earthing system, as a result of single-phase ground fault, earth fault  Circuit breaker  not only along the cable back into the surface of the conductor, but also could not fault along the cable back into the conductor surface, it must be installed by the cable head ground zero sequence CT, so as to ensure the faulted phase and non-fault phase current through the ground capacitance, which can prevent external fault protection device malfunction, but also to ensure  electric meter  of equipment failure. For IT earthing system, generally installed on the neutral line N zero sequence CT, on the low  mcb circuit breaker  side of the zero-sequence CT busbar must be installed in the neutral line N and the work of ground (or repeating ground) between the busbars . Such as zero-sequence CT installed in the N line distribution panel busbars, power distribution panel metal housing because generally associated directly with the ground electrode, when the bus is shorted to ground occurs, the resulting fault current Id metal casing along the distribution panel transformer neutral grounding line flow, rather than through the zero sequence CT, not up to the demands of the protection function, which is in the on-site construction can easily neglect.

Zero sequence current protection specific applications in three-phase line

Zero sequence current protection specific applications can be installed one each on the three-phase line current transformer (CT), or let the three phase wires together through a  Circuit breaker  CT, can also be installed on a neutral line N zero sequence CT, the use of these CT to detect the phase current vector and that the zero-sequence current Io, IA + IB + IC = Io, when the line is connected to the three-phase load on the full balance (without ground fault, and does not consider the lines, electrical  electric meter  leakage current), Io = 0; when the line connected on the three-phase load imbalance, then Io = IN, at this time of the zero-sequence current  electric transformer  current iN; when one phase ground fault occurs, inevitably produce a single ground fault current Id, at this time the detected zero-sequence current IO = IN + Id, a three-phase and single-phase unbalanced current vector sum of currents.

Adapt to zero-sequence current transformer

Zero sequence current transformer is the cable type, using ABS plastic shell, resin casting, fully sealed; using insulating oil cooling cutting process, effectively avoiding the transformer in the long-term use in the process of corrosion.  electric transformer , beautiful appearance. High sensitivity, good linearity, reliable operation,  Circuit breaker  installation. Its performance is superior to the general zero-sequence current transformer, using a wide range, not only for  air circuit breaker  relay, but also apply to electronic and computer protection device. Users can run the system approach effectively earthed neutral or non-effectively grounded neutral point difference, the choice to adapt zero sequence current transformer.

Induction meter for process requirements

Induction meter high requirements on the process, materials cover a wide range, metal, plastic, gems, glass, rare earth, which, products related materials are clearly defined standards and requirements. With cheap inferior materials instead of standard materials,  mcb circuit breaker  products that affect the quality of one of the major problems, so like most commodities, low commodity prices will not have a good quality assurance. Energy meter complex process, but the production technology is  electric meter  and stable, but also a comprehensive package tooling equipment. Production environment, temperature, humidity and air purification higher degree Circuit breaker  energy meter: is the use of analog or digital circuits to get the product of voltage and current vectors, and then through analog or digital circuits metering functions. Due to the application of digital technology, sharing billing meter, prepaid energy meter, energy meter multi-user, multi-function meter have appeared, further meet the science of electricity, reasonable demand for electricity.

Electricity meter using the meter charge mode terminal operator

Smart meter electricity meter terminal using the estimated cost way. My state is using the smart meter's verification department authorized by the State certified by the measuring  Electric transformer , all of the test items are in strict accordance with the relevant rules of order the items, the performance parameters of the product indicators do strict checks to ensure that equipment out of the All test items per meter are  power transformers  pilot. Have questioned the accuracy of the smart meter customers can go to the operating room for re-checking power supply, power supply enterprise staff will accompany the body to the verification of measuring instruments calibration again.

Using both mechanical energy meter energy meter or single function electronic energy meter

Currently, most electricity customers are using mechanical energy meter energy meter or single function electronic energy meter, while smart meters by the measurement unit, a data processing unit, a communication unit and other components, is based on the energy measurement focus expanded information storage and processing air circuit breaker , automatic control, information exchange and other functions of energy meter, but also to achieve distributed power metering, two-way interactive services, smart home, smart cell technology base, with high accuracy,  mcb circuit breaker  deductions, price inquiries, capacity memory, balance alarm, remote  Circuit breaker  of information such features. Users can use the electricity in recent months to develop electricity from the line plan, according to Guang Shan alarm recharge time, to avoid the inconvenience of power outages arrears to achieve understand the consumer, plans electricity, efficient energy. Power supply companies can provide users real-time smart metering of electricity information to help customers optimize the power consumption, analyzing the cost of electricity, to provide customers with a more in-depth range of energy management services.

2013年8月25日星期日

Anti-shake electrical contactor powerful pull system

Anti-shake electrical contactor dual set of coils, pull fast, powerful, excellent operating characteristics. mcb circuit breaker or release time, neat, no harmful jitter, avoiding the loss of pressure occurs when the power grid caused by electric meter contacts welding, thus reducing contact wear. · Circuit breaker technology, the installation angle of the ± 30o. · Controller attached to the side of the contactor, small size and high reliability. · Use the power energy storage principle, to achieve delay release. · Standards · G4M20310-2364-E-16 · QB/440100-29-0459-2005 · Q/BUP01-2004.

Anti-shake function electric AC contactor

Anti-shake electrical contactor for AC 50HZ, 60HZ, rated working voltage up to 1140V power system and breaking the circuit for continuous production line of work because of lightning, and other power transformers short circuit occurs cb circuit breaker instantaneous loss of pressure, loss of power (commonly known as Akira power) to maintain contact is not tripped. The operation is switched on. Breaking with Voltage stabilizer contactors are identical. When the outage exceeds definite time period, the contactor tripping, reaching escaped Akira power to maintain continuous production downtime purposes.