Power system voltage levels include 220/380V (0.4 kV), 3 kV, 6 kV, 10 kV, 20 kV, 35 kV, 66 kV, 110 kV, 220 kV, 330 kV, and 500 kV. With the improvement of the electric motor manufacturing process, 10 kV motors have been mass-produced, so 3 kV, 6 kV have been used less often, and 20 kV and 66 kV are rarely used. The power supply system is dominated by 10 kV and 35 kV. The transmission and distribution system is mainly above 110 kV. There are two kinds of power plant generators, 6 kV and 10 kV, and now 10 kV is the main one, and the users are 220/380V (0.4 kV) low-voltage system.
According to the "Urban Electricity Network Provisions Design Rules", the transmission network is 500 kV, 330 kV, 220 kV and 110 kV, the high-voltage distribution network is 110 kV and 66 kV, the medium-voltage distribution network is 20 kV, 10 kV and 6 kV, and the low-voltage distribution network is 0.4 kV (220V/380V).
The power plant sends out 6 kV or 10 kV electricity, and in addition to the power plant's own use (factory power), it can also be sent to the users near the power plant with 10 kV voltage. 10 kV power supply range is 10 Km, 35 kV is 20~50 Km, 66 kV is 30~100 Km, 110 kV is 50~150 Km, 220 kV is 100~300 Km. 330 kV is 200~600 Km, and 330 kV is 200~600 Km, 330 kV is 200~600Km, 500 kV is 150~850Km.
2. Types of substations
Electric power system voltage levels are converted by power transformers, voltage rise for step-up transformers (substations for step-up stations), voltage reduction for step-down transformers (substations for step-down stations). A voltage into another voltage selection of two coils (winding) of the double-turn transformer, a voltage into two voltage selection of three coils (winding) of the three-turn transformer.
Substation in addition to step-up and step-down points, but also the size of the hub station, regional station and terminal station. Hub station voltage level is generally three (three-turn transformer), 550kV / 220kV / 110kV. regional stations generally also have three voltage levels (three-turn transformer), 220 kV / 110kV / 35kV or 110kV / 35kV / 10kV. terminal station is generally directly connected to the user, most of the two voltage levels (two-turn transformer) 110kV / 10kV or 35 kV / 10kV. The user's own substation is generally only two voltage levels (two-turn transformer) 110 kV /10kV, 35kV /0.4kV, 10kV /0.4kV, of which 10kV /0.4kV is the most.
3. Substation primary circuit wiring program
1) Primary wiring type
Substation primary circuit wiring refers to the transmission line into the substation, all the power equipment (transformers and inlet and outlet switches, etc.) of the interconnection method. Its wiring scheme: line transformer group, bridge wiring, single bus, single bus segmentation, double bus, double bus segmentation, ring network power supply.
2) line transformer group
Substation only one way into the line with a transformer, and then no development of the case using line transformer group wiring.
3) Bridge connection
There are two incoming lines and two transformers, and there is no further development, the bridge connection is used. For transformers, the contact breaker is inside the two incoming circuit breakers for internal bridge wiring, and the contact breaker is outside the two incoming circuit breakers for external bridge wiring.
4) single bus
Substation in and out of the line is more, the use of single bus, there are two incoming, generally all the way to power, a standby (not at the same time), the two can be equipment with the power supply mutual self-transfer, more out of the line by a section of the bus lead out.
5) single bus segmentation
There are more than two incoming, multiple outgoing, the choice of single bus segmentation, two incoming respectively to the two sections of the bus, the two sections of the bus with the bus switch connected. Outgoing lines are connected to the two sections of the bus.
Single bus segmentation operation is more. Generally all the way to the main supply, a standby (not closed), the bus joint, when the main supply power failure, standby closed, main supply, standby and bus interlocking. Standby power capacity is small, standby power closed, to disconnect some outgoing lines. This is a more commonly used mode of operation.
For particularly important loads, both incoming lines are the main supply, the bus switch is disconnected, when one incoming line is disconnected, the bus is closed, and the incoming call disconnects the bus and then closes the incoming switch.
Single bus segmentation is also conducive to the substation internal maintenance, maintenance can stop a section of the bus, if the single bus is not segmented, maintenance will be the whole station blackout, the use of bypass bus can be non-stop, bypass bus is only used for power system substations.
6) double bus
Double bus is mainly used in power plants and large substations, each route by a circuit breaker through two disconnect switches were connected to two buses, so that in the bus maintenance, you can use the disconnect switches will be reversed in a condition of the bus line. Double bus also has two kinds of segmentation and non-segmentation, double bus segmentation and then add bypass circuit breaker, wiring is complex, but maintenance will be very convenient, the scope of power outages can be reduced.
4. Secondary circuits of power substation
1) Types of secondary circuits
Secondary circuits of power substation include: measurement, protection, control and signaling circuits. Measurement circuit includes: measurement and protection measurement. The control circuit includes: local manual closing and closing, anti-tripping interlock, test, mutual interlock, protection tripping and closing and closing execution part. Signal circuit includes switch operation status signal, accident trip signal and accident preview signal.
2) Measurement circuit
The measurement circuit is divided into current circuit and voltage circuit. Current circuit of various devices in series with the secondary side of the current transformer (5A), the current transformer is the original side of the load current into a unified 5A measurement current. Measurement and protection with their respective transformers (measurement with high accuracy requirements of the transformer), measurement measurement in series with the ammeter and meter, power meter and power factor meter current terminals. Protection measurement is connected to the current terminals of the protection relay. Microcomputer protection will generally be measured and protection is concentrated in one, respectively, measurement current terminals and protection current terminals.
Voltage measurement circuit, 220/380V low-voltage system directly connected to 220V or 380V, 3KV or more high-voltage system all through the voltage transformer will be a variety of levels of high voltage into a uniform 100V voltage, voltmeter, as well as the meter, power meter and power factor meter voltage coils through its terminals and connected to the 100V voltage bus. Microcomputer protection unit metering voltage and protection voltage is unified into a voltage terminal.
3) control circuit
(1) closing and splitting circuit
Closing and splitting circuit through the closing and splitting changeover switch for operation, conventional protection for the prompting of the operator and the accident tripping alarm needs, the changeover switch selection of the pre-closing - closing - closing and pre-splitting - splitting - splitting after the multi-grade changeover switch. In order to utilize the non-corresponding wiring for closing and splitting prompts and accidental tripping alarm, the state has a standard diagram design. After the use of microcomputer protection, to be far after the closing operation, but also to the local transfer switch alignment operation, which loses the significance of the operation of the far, so it should be canceled does not correspond to the wiring, the choice of the middle of the self-resetting only the closing and splitting of the three-stage transfer switch.
(2) anti-tripping circuit
When the closing circuit faults for the breaking, or short-circuit accident is not ruled out, and closing (misoperation), then there will be a circuit breaker repeatedly closing and splitting, not only easy to cause or expand the accident, but also cause damage to the equipment or personal accidents, so the high-voltage switching control circuit should be designed to anti-tripping. Anti-tripping is generally used to start the current, voltage holding double-coil relay. The current coil is connected in series to the breaking circuit as the starting coil. The voltage coil is connected to the closing circuit as a holding coil, and the current coil is activated by the opening circuit when the gate is opened. If there is a fault in the closing circuit, or in the manual closing position, the voltage coil starts and self-holds through its normally open contact, and its normally closed contact immediately breaks the closing circuit to ensure that the circuit breaker cannot be reclosed immediately during the opening process. The current circuit of the anti-trip relay can also self-hold the current coil through its normally open contact, which can reduce the load of the protective relay's exit contact disconnection, and also reduce the holding time requirements of the protective relay.
Some microcomputer protection devices have their own anti-trip function, so you can no longer design anti-trip circuit. Circuit breaker operating mechanism selected spring energy storage, if the selection of energy storage can be used after a spring energy storage operating mechanism (also used for reclosing energy storage can be used after the second closing and breaking spring energy storage operating mechanism), because the energy storage generally require about 10 seconds, when the energy storage switch is often in the disconnected position, storage of a time when the energy storage, close after the energy storage switch is then in the disconnected position, can jump a gate; after tripping the energy storage switch is then in the disconnected position, can jump a gate; after tripping the energy storage switch is then in the disconnected position, can jump a gate; after the tripping of the energy storage switch is then in the disconnected position, can jump a gate. Can be tripped once; after tripping, to manually store energy before closing, at this time, can also no longer design anti-trip circuit.
(3) test and mutual interlocking and control
For the handcart switchgear, after the handcart is launched to carry out circuit breaker closing and splitting test, should be designed to close and split the test button. Into the line with the busbar disconnect, generally should be required to interlock or control of mutual investment.
(4) protection trip
Protection trip exit through the connecting piece connected to the trip circuit, the connecting piece is used to protect the debugging, or operation process to lift some of the protection function.
(5) Closing and splitting circuit
Closing and splitting circuit is to provide power for the operating mechanism through the closing and splitting bus, as well as its control circuit, generally should be drawn separately.
4) Signal circuit
(1) switching operation status signal by the closing and breaking instructions for the two signal lamps mounted on the switchgear: through the operation of the changeover switch does not correspond to the wiring connected to the positive power supply. After the adoption of microcomputer protection, the transfer switch canceled the non-corresponding wiring, so the positive pole of the signal lamp can be directly connected to the positive power supply.
(2) accident signals have accident trip and accident preview two kinds of signals, accident trip alarm also through the conversion switch does not correspond to after receiving the accident trip signal bus, and then lead to the central signaling system. Accident preview signal through the signal relay contact to the central signaling system. After the adoption of microcomputer protection, the auxiliary contact of the circuit breaker operating mechanism and the contact of the signal relay are respectively connected to the switching input terminals of the microcomputer protection unit. When a central signaling system is required, if the microcomputer protection unit can provide the output contact of accident trip and accident preview, it can be led to the central signaling system. Otherwise, another pair of contacts of the signal relay should be used to lead to the central signaling system.
(3) the central signaling system for the installation of the centralized alarm system in the watchman's office, by the accident trip and accident preview two sets of sound and light alarm, light alarm with a light sign, without signal lamps, light signs are centralized and decentralized two kinds. After the use of substation automation system, you can no longer design the central signaling system, or simplify it, only the design of the centralized alarm as a backup alarm computer alarm.
5. substation relay protection
1) the role of substation relay protection
The substation relay protection can be in the substation during the operation of faults (three-phase short-circuit, two-phase short-circuit, single-phase grounding, etc.) and abnormal phenomena (overload, over-voltage, under-voltage, low peripheral wave, gas, over-temperature, control and measurement circuit disconnection, etc.). Rapidly and selectively issue a trip command to remove the fault or issue an alarm, thereby reducing the scope of power outages caused by faults and the extent of damage to electrical equipment, to ensure the stable operation of the power system.
2) substation relay protection basic working principle
The substation relay protection is based on the substation faults occurring in the course of the operation of the substation increase in current, voltage increase or decrease in frequency, gas, temperature rise and other phenomena over the set value of the relay protection (given value) or exceed the limit value in the set time, selective tripping commands or alarm signals. Alarm signal.
The selective tripping according to the current value is the inverse time limit, the larger the current value, the faster the tripping. Selective tripping according to the time is called fixed time protection, fixed time in the fault current exceeds the set value, after the time set value of the time given by the trip command. Gas and temperature etc. are non-electrical protection.
Reliability coefficient is an empirical data, the calculation of the relay protection action value, to multiply the results of the calculation by the reliability coefficient to ensure that the relay protection action is accurate and reliable, the range of 1.3 ~ 1.5.
The occurrence of a fault in the minimum and the protection of the action value of the ratio of the sensitivity factor of the relay protection, generally 1.2 ~ 2, according to the design specification should be selected.
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3) substation relay protection according to the nature of protection
4) substation relay protection according to the protected object classification
(1) generator protection
generator protection stator winding phase-to-phase short-circuit, stator winding grounding, stator winding turn-to-turn short-circuit, generator short-circuit external, symmetrical overload, stator winding over-voltage, a point of excitation circuit and two-point grounding, demagnetization fault. Two-point grounding of excitation circuit, demagnetization fault, etc. The way of exit is to stop the generator, unplug the generator, reduce the scope of influence of the fault and send out a signal.
(2) power transformer protection
Power transformer protection has a winding and its lead wire phase-to-phase short circuit, neutral point directly grounded side of the single-phase short circuit, winding turn-to-turn short circuit, external short circuit caused by overcurrent, neutral point directly grounded in the power network caused by the external grounding short circuit overcurrent and neutral over-voltage, overload, the oil level is lowered, the temperature of the transformer rises, the oil tank pressure or the cooling system failure. Cooling system failure.
(3) line protection
Line protection according to the different voltage levels, grid neutral grounding different ways, transmission lines and cables or overhead lines of different lengths, respectively: phase-to-phase short-circuit, single-phase short-circuit, single-phase grounding, overloading and so on.
(4) bus protection
Power plants and important substation bus should be equipped with special bus protection.
(5) power capacitor protection
Power capacitors have capacitor internal faults and their lead wires short-circuit, short-circuit capacitor bank and circuit breaker between the connecting line, capacitor bank in a fault capacitor removal caused by over-voltage, capacitor bank over-voltage, the bus connected to the voltage loss.
(6) high-voltage motor protection
High-voltage motors have stator winding phase-to-phase short circuit, stator winding single-phase grounding, stator winding overload, stator winding low voltage, synchronous motor out of step, synchronous motor demagnetization, synchronous motor out of synchronization inrush current.
6. Microcomputer protection devices
1) Advantages of microcomputer protection
(1) high reliability: a microcomputer protection unit can complete a variety of protection and monitoring functions. Instead of a variety of protection relays and measuring instruments, it simplifies the wiring of the switchgear and control panel, thus reducing the failure of the relevant equipment links and improving reliability. Microcomputer protection unit using highly integrated chips, software with automatic detection and automatic error correction functions, but also to improve the reliability of the protection.
(2) high precision, speed, multi-function. The digitization of the measurement part greatly improves its precision, the CPU speed can be improved so that various events can be timed by m s, and the improvement of software functions can be completed through a variety of complex algorithms for a variety of protection functions.
(3) flexibility, through the software can easily change the protection and control characteristics, the use of logic judgment to achieve a variety of interlocks, a type of hardware using different software, can constitute a different type of protection.
(4) maintenance and debugging is convenient, less types of hardware, line unity, external wiring is simple, greatly reducing the maintenance workload, protection, debugging and adjustment of the use of input buttons or above the computer downlink, debugging is simple and convenient.
(5) good economy, high performance-price ratio, due to the multifunctionality of the microcomputer protection, so that the substation measurement, control and protection part of the comprehensive cost reduction. High reliability and high speed, can reduce the power outage time, save manpower, improve the economic efficiency.
2) microcomputer protection device features
Microcomputer protection device in addition to the advantages of the above microcomputer protection, compared with similar products have the following characteristics:
(1) complete varieties: microcomputer protection device, the varieties of particularly complete to meet the various types of substation power distribution station of various types of equipment for a variety of protection requirements, which gives the design of the substation power distribution station and computer networking Provides a great convenience.
(2) hardware using the latest chips to improve the technical sophistication, the CPU uses 80C196KB, measurement for 14-bit A/D conversion, analog input loop up to 24 ways, the data collected with DSP signal processing chip for processing, the use of high-speed Fourier transform, to get the fundamental wave to the 8th harmonic, special software auto-correction, to ensure that the measurement of high precision. Utilizing dual-port RAM and CPU to transform the data, it constitutes a multi-CPU system, and the communication adopts CAN bus. Has a high communication rate (up to 100MHZ, generally running at 80 or 60MHZ) anti-interference ability and other characteristics. Through the keyboard and liquid crystal display unit can be convenient for on-site observation and a variety of protection methods and protection parameter settings.
(3) Hardware design in the power supply, analog input, switch input and output, communication interfaces and other special isolation and anti-jamming measures, anti-jamming ability, in addition to the centralized group screen, can be installed directly on the switchgear.
(4) The software is rich in functions, in addition to various measurement and protection functions, through the cooperation with the upper processing computer, it can complete the fault recording (1-second high-speed fault recording and 9-second fault dynamic recording), harmonic analysis and small-current grounding and routing functions.
(5) RS232 and CAN communication can be selected, supporting a variety of remote transmission protocols, convenient and various computer management system networking.
(6) using a wide temperature band background 240 × 128 large screen LCD liquid crystal display, easy to operate, beautiful display.
(7) high degree of integration, small size, light weight, easy to centralize the group screen installation and decentralized installation in the switchgear.
3) The use of microcomputer protection devices
(1) Small and medium-sized power plants and their step-up substations.
(2) 110 kV /35 kV /10 kV regional substations.
(3) 10 kV opening and closing stations of urban 10 kV grids
(4) 110 kV /10 kV or 35 kV /10 kV general bucking stations for customers.
(5) User 10 kV substation
4) Types of microcomputer protection devices
(1) microcomputer protection devices **** there are four major categories.
(2) Line protection devices
Microcomputer line protection devices Microcomputer capacitor protection devices Microcomputer directional line protection devices
Microcomputer zero-sequence distance line protection devices Microcomputer cross-differential current directional line protection devices
(3) Main equipment protection devices
Microcomputer double-winding transformer differential protection devices Microcomputer three-winding transformer differential Microcomputer transformer backup protection device Microcomputer generator differential protection device Microcomputer generator backup protection device
Microcomputer generator backup protection device Microcomputer motor differential protection device Microcomputer motor protection device
Microcomputer plant (station) substation protection device
(4) Measurement and control devices
Microcomputer telemetry remote control device Microcomputer telemetry remote control device Microcomputer telecontrol device Microcomputer remote adjustment device Microcomputer automatic quasi-simultaneous device
Microcomputer self-provisioning device Microcomputer PT switching device Microcomputer impulse power measurement device
Microcomputer multifunctional transformer measurement device Microcomputer de-linking device
(5) Management device unit
Communication unit management unit Dual-computer management unit
5) Microcomputer Protection device function
Microcomputer protection device of the general technical requirements and indicators (working environment, power supply, technical parameters, device structure) and the main functions (protection performance indicators, the main protection function, the principle of protection, the fixed value and parameter settings, as well as the external terminals and the secondary diagram) are described in detail in the relevant product specifications.
7. 220/380V low-voltage power distribution system microcomputer monitoring system
1) 220/380V low-voltage power distribution system features
(1) a wide range of applications, now the industrial and civil power supply in addition to mines, medical care, hazardous materials storehouse, etc., are 220/380V, so the scope of application is very broad.
(2) low-voltage distribution systems are generally TN-S, or TN-C-S system. TN-C system for three phase (A, B, C) and a neutral (N), N line in the transformer neutral grounding or in the building into the house. The N line is grounded at the neutral point of the transformer or repeated at the building entry point. Transmission line is four wires, cable is four cores, no protective earth (PE), one less wire. Equipment shell, metal conductive part of the protective grounding connected to the neutral (N), known as the zero system, zero system security is poor, interference with electronic equipment, design specifications have been stipulated no longer used.
TN-S system for the three-phase, a neutral (N) and a protective earth (PE). N and PE lines in the transformer neutral centralized grounding or repeated grounding in the building into the house line. The transmission line is five, the cable is five cores. The neutral (N) and the protective earth (PE) are connected together at the grounding point and can no longer have any connection, so the neutral (N) must also be insulated. Neutral line (N) lead out if you do not use insulation to the ground insulation, or lead out and protective earth line has a connection, although the use of five wires, but also for the TN-C system, which should be especially noted. TN-S or TN-C-S system security is good, on the TN-S or TN-C-S system security is good, small interference with electronic equipment, you can *** with the grounding wire (CPE),, the use of equipotential connection security is better, less interference. Therefore, the design specification provides that in addition to special places, are used TN-S or TN-C-S system.
(3) 220/380V low-voltage distribution system protection is still using low-voltage circuit breakers or fuses. So 220/380V only monitoring and control without protection. Monitoring includes current, voltage, degree, frequency, power, power factor, temperature and other measurements (telemetry), switch operating status, accident trip, alarm and accident preview (overload, overtemperature, etc.) alarm (telecom) and the electric switch remote closing and splitting operation (remote control) and other three contents (referred to as the three remotely), and there is no protection.
(4) 220/380V low-voltage distribution system circuit are generally single bus or single bus segmentation, two or more transformers are single bus segmentation, there are several transformers are divided into several segments, this is because the user substation transformers are generally not used in parallel operation, which is to reduce the short-circuit current, reduce the short-circuit capacity, or else, the low-voltage circuit breaker to increase the capacity of the disconnect.
(5) 220/380V low-voltage distribution system into the line, bus, large loads out of the line with the low-voltage contact line because of the capacity, generally all the way (1 circuit breaker) occupies a low-voltage cabinet. According to the different size of the power supply load current, a low-voltage switchgear cabinet with two outlets (installation of two circuit breakers), four outlets (installation of four circuit breakers), as well as five, six, eight and ten outlets, unlike the high-voltage distribution system, a circuit breaker occupies a switchgear cabinet. Therefore, the low-voltage monitoring unit should be used for all the way, two or more points, the design should be based on the number of outgoing circuits of each low-voltage switch and low-voltage monitoring unit specifications to design.
(6) low voltage circuit breaker in addition to manual operation, but also can choose electric operation. Large-capacity low-voltage circuit breakers generally have manual and electric operation, the design should be selected with remote control of the low-voltage monitoring unit, small-capacity low-voltage circuit breakers, design, most of the selection of only manually operated circuit breakers, so that the low-voltage monitoring unit of the remote exit can not be wired, or the selection of low-voltage monitoring unit without remote control.
2) 220/380V low-voltage distribution system microcomputer monitoring system design
(1) 220/380V low-voltage distribution system microcomputer monitoring system, first of all, according to the primary system and the user's requirements for telemetry, telemetry and remote control design.
(2) Measurement circuit design
A Measurement part of the secondary wiring is the same as the high-voltage, the current loop is connected in series to the secondary circuit of the voltage transformer, and the voltage loop is connected in parallel to the voltage measurement circuit. As 220/380V low-voltage distribution system without voltage transformer, voltage measurement can be directly connected to the 220/380V bus, and the meter voltage circuit can generally not add fuse protection, but the cabinet wiring should be as short as possible, when possible, it is best to add fuse protection to facilitate maintenance.
B power measurement can be used to bring their own power with pulse output pulse meter, for the calculation of power and electricity function of the low-voltage monitoring unit, only as an internal billing, you can no longer use the pulse meter.
C Selection of low-voltage monitoring unit with a display function, you can no longer design current and voltmeter, selection of low-voltage monitoring unit without display function should also be designed current or voltmeter, should not be designed both.
(3) signaling circuit design
Design, low-voltage circuit breaker to increase a pair of normally open contacts to the low-voltage monitoring unit switching status input terminals. If there is an accident trip alarm output contact, then it will be connected to the accident preview terminal of the low-voltage monitoring unit.
(4) remote control circuit design
Low-voltage monitoring system remote control design is relatively simple, electric operation of low-voltage circuit breakers have a pair of closing and splitting buttons, as long as the low-voltage monitoring unit closing and splitting output terminals and in the closing and splitting buttons can be, if necessary, can be designed to a local and remote control operation of the change-over switch, to prevent local maintenance of the switch, the remote operation of the accident.
(5) power supply and communication cable design
Low-voltage monitoring unit power supply for AC 220V power supply, power consumption is generally only a few watts, the design of the power supply from the terminal to a 220V/5A two-pole low-voltage circuit breaker, and then lead to the switchgear terminal, and then unified with the KVV-3 × 1.0 cable centralized to the low voltage cabinet all the way to the small capacity outlets. Low-voltage cabinet all the way to a small capacity out of the line. A UPS power supply can be added when needed.
Communication cable general distance does not exceed 200 meters can choose KVV-3 × 1.0 ordinary shielded control cable, more than 200 meters should be shielded twisted-pair cable (preferably with a sheath type) or computer communication cable.
8. Substation automation system
1) System Composition
High-voltage microcomputer protection, low-voltage monitoring unit, and then the communication cable will be networked with the computer can be composed of a modern substation management system - substation automation system.
2) substation automation system design
A high-voltage microcomputer protection unit (group screen or installed in the switchgear) selection and design of the secondary diagram.
B low-voltage microcomputer monitoring unit (installed in the switchgear) selection and design of the secondary diagram.
C management computer (placed in the duty room, unmanned can be placed in the power dispatching room) selection.
D analog disk (placed in the duty room or dispatching room) design.
E upper computer (with the plant computer or power department scheduling network) networking program design.
F communication cable design (including management computer and the host computer).
3) Management computer
Management computer can be configured according to system requirements.
4) analog disk
Users require an analog disk, you can design the analog disk, small systems can be wall-mounted, large systems with floor-to-ceiling, the analog disk size according to the power supply system once the map and the area of the duty room to decide. Analog disk using a dedicated control unit, its communication cable to the management computer. Analog disk also needs all the way AC 220V power supply, capacity is only a few dozen watts, the design should be considered together with the management computer power supply.
5) substation automation system main functions
Substation automation system management computer through the communication cable and installed in the field of all microcomputer protection and monitoring unit for information exchange. Management computer can send down the remote control operation command and the relevant parameter modification, at any time to accept the microcomputer protection and monitoring unit up to the telemetry, telemetry and accident information. Management computer can be processed through the information, storage and preservation, through the record printing and screen display, but also to analyze the operation of the system, through the telematics can be found at any time to deal with accidents, reduce the accident blackout time, through the remote control can be reasonable allocation of the load, to achieve optimal operation, thus providing the necessary conditions for the realization of the modernization of the management.
Management computer software to be standardized, the operation should be simple and convenient, good man-machine interface, convenient configuration, user use and secondary development is simple and easy to master.