The central signal system (centresignalsystem) is set on the main control panel to centrally monitor the electrical and lighting signal system of the substation electrical equipment faults and abnormal conditions. The central signal system usually consists of an accident signal device, a warning signal device (collectively referred to as a central signal device), and a monitoring circuit of the circuit breaker and the electrical device. Its role is to facilitate the on-duty personnel and dispatchers to understand and deal with electrical equipment failures and abnormal conditions to ensure the normal operation of the substation.
Commonly used central signaling devices consist of electromagnetic relays or transistors, integrated logic circuit components. According to the different sound signal action and reset mode, it is divided into repeated action and non-repetitive action, automatic reset and manual reset, etc., thus forming a central signal device circuit with different functions. Traction substation and railway substation under normal circumstances, due to the small number of circuit breakers and fast switches, most of them use the central reset signal, non-repetitive action signal circuit, and the warning signal uses the central reset, repeated action circuit.
The electromagnetic central signal device with central reset and non-repetitive action is realized by a circuit consisting of several intermediate relays, flash relays, acoustic devices (buzzers and bells), several signal small bus bars and various case switches. When the accident signal device is automatically opened by the circuit breaker accident, the position of the control switch does not correspond to the actual position of the circuit breaker (referred to as the principle of non-correspondence), which causes the small bus of the accident signal to be charged and the accident signal relay to start, the buzzer The loop is turned on and the sound is loud. When the central signal device disc presses the contact acoustic signal button switch (or is automatically completed by the action of the intermediate relay contact), the acoustic signal relay circuit is turned off to release the sound (return). The accident signal circuit is blocked by the self-holding contact of the canceling sound relay in the bribe of the audible signal button switch, and at the same time, if the second circuit breaker has an accidental trip, the buzzer does not sound, thus It is not repeated. However, when the circuit breaker control switch is reset (corresponding to the opening position), the accident signal small busbar is ten points, and the new accident information can still be accepted again. The circuit principle of the electromagnetic central warning signal device with central reset and non-repetitive action is similar to that of the above-mentioned accident signal device, but the activation of the warning signal relay is realized by the action of various monitoring relays in which the device is in an abnormal state.
Electromagnetic central signal device with central reset and repetitive action. The accident or warning signal device ensures that the core period and the starting component of the repetitive action are shock relays composed of a pulse current transformer, a sensitive spring relay and an exit relay, and several signals are set. The small busbar, the accident or the warning signal is automatically reset after the impact relay is actuated by the corresponding small busbar, the other circuit breaker is opened by the accident, or the other monitoring relay acts in the abnormal state of the equipment, due to the serial connection in the pulse relay The loop resistance of the input loop (in this case, two sets of parallel light-emitting brand lamp resistors) changes, causing the pulse current of the pulse converter to suddenly increase, and the pulse relay is activated again, thereby achieving repeated action.
At the same time that the equipment has an accidental audible signal, the circuit breaker position signal of the accident trip flashes, indicating the location of the accident. In addition, it should be able to directly display the nature of the accident on the light plate of the central signal device, so that the operator can judge and handle the accident in time.
The notice signal usually only has the instantaneous notice information. When an abnormal operation occurs, the light board displays the light signal while the sound signal is being emitted. For some transient signals, such as the short-term disappearance of the DC power supply, it may be quickly eliminated. If the sound is emitted, it will interfere with the attention of the duty officer and four digits, so the warning signal can be delayed by 0.3s~0.5s. For individual signals that require long delays, such as overload signals, etc., it can be implemented by adding a time relay. The sound of the warning signal can be manually reset, or it can be wired with automatic delay reset.
A test loop is set up for both the accident warning signal and the warning signal bribe. A power outage clock loop can also be set up when an accident warning signal occurs to determine when the accident occurred. The power supply of the central signal system can be either a strong power source or a weak power source. Strong power control can use strong or weak electric signals; weak electric power line control mostly uses weak electric signals.
Another component of the central signal system is the position signal included in the circuit breaker control circuit (see the substation control system). The position signals of the circuit breaker are both light monitoring and acoustic monitoring. The light monitoring usually has a traffic light, the red light indicates the closing state, and the green light indicates the opening state. The acoustic monitoring signal typically indicates the position of the circuit breaker with a light embedded in the handle of the control switch.
The central signal device of the transistor and the integrated logic circuit is composed of a pulse forming loop, an inverter, a monostable flip-flop with a memory function, a delay and reset loop, and a flash power supply component. The pulse forming circuit of the trotters receives the input current and converts into a pulse signal, and the inverter and the single-stabilizer form a starting link, and perform a function of turning on or delaying the sound signal to make it occur; And when it is reset, the acoustic signal is released. The delay and reset loops perform automatic reset of the acoustic signal and manual release of the sound. The device can be used for repetitive work.
The components of the central signal device are powered by a self-contained voltage regulator. The function, operation and test situation of the whole device are basically the same as those of the electromagnetic central signal device, but it has a small volume, fewer secondary circuit lead-out contacts, non-contact and reliable operation of the main components, and is gradually popularized by people. application.
The realization of the central signal of the microcomputer monitoring system When the substation adopts the microcomputer-based hierarchical distributed digital monitoring system, the electrical equipment, the line data acquisition module, the control module and the monitoring host can exchange information in real time, and monitor the state of the device. Control, and can realize the CRT screen monitoring and display of the main wiring diagram operating conditions of the substation. When the circuit breaker accident is opened, the CRT screen automatically exits the fault of the circuit breaker pattern by the switch displacement processing and logic operation. The display and the analog light plate are flat, and the accident alarm is activated, the sound alarm signal is also activated, the accident sound is emitted, and the printer prints out all accident information and parameters. Thereby achieving various functions of the central accident signal. The central notice signal is realized by monitoring the electric quantity parameter and the electric quantity upper and lower limit values ​​of the electrical equipment. In the abnormal situation and over the limit, the over-limit alarm can be issued, and the CRT screen automatically displays the relevant parameters and starts the printer. Printout.
Compared with the functions of the traditional central signal device, the microcomputer monitoring system adds functions such as screen display and record printing and storage, providing convenient and scientific monitoring means for the duty personnel. Central signal and control, monitoring, relay protection and RTU integration constitute an integrated integrated automation system, which can comprehensively improve the automation and intelligent management level of the substation and enhance the overall function (see the substation integrated automation system). The development trend.High Capacity Pvc Pe Pipe Production Line,Precision Pvc Pe Pipe Production Line,Affordable Pvc Pe Pipe Production Line,Customizable Pvc Pe Pipe Production Line
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