One, what is electrical once, twice?

Reflected in the electrical equipment and secondary equipment on the difference between:

 A device is a high-voltage electrical device that is used directly in the production, delivery and distribution of electrical energy. It includes generators, transformers, circuit breakers, disconnectors, automatic switches, contactors, knife switches, busbars, transmission lines, power cables, reactors, motors and so on.

By a device connected to each other, constitute the power generation, transmission, distribution or other production process of electrical equipment known as a device.

Secondary equipment refers to the work of a device to monitor, control, regulation, protection and operation, maintenance personnel to provide operating conditions or production of command signals required for low-voltage electrical equipment. Such as fuses, control switches, relays, control cables, and so on.

By the secondary equipment connected to each other, constitute a primary equipment for monitoring, control, regulation and protection of electrical equipment known as the secondary equipment.

 

Second, the electrical classification once

Electrical primary equipment according to its role in the production can be divided into six categories:

(1) equipment for the production and conversion of electrical energy. Such as the generator will be converted into electrical energy, the motor will be converted into mechanical energy, the transformer will increase or decrease the voltage to meet the power transmission and distribution needs.

(2) Switch on or off the circuit. Such as circuit breakers, disconnectors, fuses, contactors and so on. When they are used in normal or accidental state of the power system, the circuit is closed or disconnected.

(3) limit the fault current and defense over-voltage electrical appliances. Such as limiting the short-circuit current reactor and anti-over-voltage arrester and so on.

(4) grounding device. It is buried in the ground directly with the earth in contact with the metal conductor and electrical equipment connected to the metal wire. Whether it is the work of the power system neutral grounding or protection of personal safety protection grounding, are buried in the ground connected to the ground device.

(5) Current carrying conductor. Such as bare conductors, cables and so on. According to the design requirements, the electrical equipment will be connected.

(6) AC electrical conversion equipment between the first and second times. Such as voltage and current transformers, through which the primary voltage and current are transferred to the secondary system.

Third, the electrical secondary circuit small classification

 1, control (operation) loop: by the control switch and control objects (such as circuit breakers, disconnectors) transmission mechanism, the implementation (or operation) institutions. Its role is to a device for "together", "sub" operation.

2, adjust the loop: refers to the regulation of automatic devices. Such as by the VQC system on the main transformer on-load voltage regulator device, the generator excitation adjustment device. It consists of a measuring mechanism, a conveying mechanism, a regulator and an actuator.

Its role is based on a device operating parameters of the changes, real-time online adjustment of the working state of a device to meet the operational requirements.

3, relay protection and automatic device circuit: by the measurement loop, the comparison part, the logic part and the implementation of the composition and so on.

Its role is based on a device and the system running state, to determine its failure or abnormal, automatically issued a trip command to selectively cut off the fault and send a corresponding signal, when the fault or abnormal disappearance, the rapid input of the circuit breaker ( Reclosing and standby power supply automatically into the device), to restore the normal operation of the system. (Note: The above is mainly refers to the conventional electromagnetic relay and other components of the protection and automatic devices)

4, measuring circuit: by a variety of measuring instruments and related circuits.

Its role is to indicate or record the operating parameters of a device and system in order to run the staff to master the operation of a system, but also the analysis of power quality, calculate the economic indicators, understand the system and the main equipment operating conditions of the main basis. (Note: integrated automation has made the demarcation point of the loop and the triple circuit more and more blurred)

5, the signal loop: by the signal transmission agencies and signal relays and other components.

Its role is to reflect the work of a secondary equipment.

 6, operating power system: from the power supply and power supply network, which often includes DC power supply system and AC power system.

Its role is to control, protect, signal and other equipment to provide power and operating power for the main transformer cooling, water and coal and other power equipment to ensure that all power plants and substation equipment to work properly.

 

 

The electrical secondary circuit connecting the protection device has the following circuits:

 (1) from the current transformer, voltage transformer secondary side of the terminal to the relevant relay protection device secondary circuit (for multi-oil circuit breakers or transformers and other casing transformers, starting from the terminal box).

(2) from the relay to protect the DC shunt fuse to the secondary circuit of the relevant protection device.

(3) from the protective device to the control panel and the central signal between the DC circuit.

(4) relay protection device outlet terminal row to the circuit breaker operation box terminal block jump, closing circuit.

(5) Current carrying conductor. Such as bare conductors, cables and so on. According to the design requirements, the electrical equipment will be connected.

(6) AC electrical conversion equipment between the first and second times. Such as voltage and current transformers, through which the primary voltage and current are transferred to the secondary system.

Third, the electrical secondary circuit small classification

 1, control (operation) loop: by the control switch and control objects (such as circuit breakers, disconnectors) transmission mechanism, the implementation (or operation) institutions. Its role is to a device for "together", "sub" operation.

2, adjust the loop: refers to the regulation of automatic devices. Such as by the VQC system on the main transformer on-load voltage regulator device, the generator excitation adjustment device. It consists of a measuring mechanism, a conveying mechanism, a regulator and an actuator.

Its role is based on a device operating parameters of the changes, real-time online adjustment of the working state of a device to meet the operational requirements.

3, relay protection and automatic device circuit: by the measurement loop, the comparison part, the logic part and the implementation of the composition and so on.

Its role is based on a device and the system running state, to determine its failure or abnormal, automatically issued a trip command to selectively cut off the fault and send a corresponding signal, when the fault or abnormal disappearance, the rapid input of the circuit breaker ( Reclosing and standby power supply automatically into the device), to restore the normal operation of the system. (Note: The above is mainly refers to the conventional electromagnetic relay and other components of the protection and automatic devices)

4, measuring circuit: by a variety of measuring instruments and related circuits.

Its role is to indicate or record the operating parameters of a device and system in order to run the staff to master the operation of a system, but also the analysis of power quality, calculate the economic indicators, understand the system and the main equipment operating conditions of the main basis. (Note: integrated automation has made the demarcation point of the loop and the triple circuit more and more blurred)

5, the signal loop: by the signal transmission agencies and signal relays and other components.

Its role is to reflect the work of a secondary equipment.

 6, operating power system: from the power supply and power supply network, which often includes DC power supply system and AC power system.

Its role is to control, protect, signal and other equipment to provide power and operating power for the main transformer cooling, water and coal and other power equipment to ensure that all power plants and substation equipment to work properly.

The electrical secondary circuit connecting the protection device has the following circuits:

 (1) from the current transformer, voltage transformer secondary side of the terminal to the relevant relay protection device secondary circuit (for multi-oil circuit breakers or transformers and other casing transformers, starting from the terminal box).

(2) from the relay to protect the DC shunt fuse to the secondary circuit of the relevant protection device.

(3) from the protective device to the control panel and the central signal between the DC circuit.

(4) relay protection device outlet terminal row to the circuit breaker operation box terminal block jump, closing circuit.

 

Electric secondary is the secondary equipment for research, management of the professional. And we want to know the electrical secondary is the division of this level.

1, relay protection: electrical important important aspects of the two, responsible for the safety of a device protection, is a safe operation of the equipment protection, commonly known as "patron", the relevant equipment to change group protection, line protection, plant protection (station Protection), fault recorder, protection and fault information sub-station (master).

2, electrical measurement, measurement: is responsible for monitoring the operation of a device to facilitate the relevant personnel to monitor, such as transmitters, ammeter, voltmeter, power meter, metering with the power meter is used for energy-saving analysis and power settlement. The professional related to the regular instrument calibration and maintenance, to ensure that the data is true and reliable.

3, automation: generally used for connection with the grid dispatching system and information exchange equipment management, common with PMU (phasor measurement device), RTU (remote device), AVC (automatic voltage control), electricity market, Charge (sub station or master station).

4, communication: responsible for the automation of data transmission equipment to provide channel and channel-related equipment maintenance, management. The main equipment is Guangduan Ji, digital patch panels, audio patch panels, administrative \ scheduling switches, fiber patch panels and other equipment.

5, automatic control: the reason why the independent, because it is different from the relay protection, automation and professional protection and automation associated. Such as excitation system, frequency conversion system, soft start device, fast cutting device is essentially an automatic control system.

 6, power supply equipment: for the secondary equipment to provide power equipment, known as power equipment. Such as 110V, 220V DC system, battery, UPS system, etc. can be called power equipment.

 

Fourth, electrical secondary control

Secondary control is a high voltage side of the voltage into a low voltage side of the voltage to control the high voltage components of the control circuit, called the second control. The answer is wrong.

Simple understanding is a load directly open and close the circuit called a line, in a line to install the AC contactor and the like, by controlling the AC contactor pull off to control the circuit of a circuit called the secondary control circuit