Source: Polaris Electric People
First, the general situation of the project
The incoming power supply of section I and section II of the 10KV substation comes from the regional substation respectively. The 10KV equipment is a three-phase AC insulated metal armored enclosed switchgear produced by Switch Co., Ltd., and the equipment is relatively advanced.
The protection is divided into: motor reverse time over-current protection, over-current protection, quick-break protection, under-voltage protection, zero sequence protection, and standby self-investment protection.
Second, the debugging process (as shown in the figure)
III. How to operate
1. Record the name brand information of electrical appliances
(1) Record the equipment model, power, rated voltage, rated current, short-circuit impedance, wiring group, and transformer ratio.
(2) Record the power cable model and specifications.
(3) Record the model and maximum breaking current of the vacuum switch.
(4) Record the model, rated voltage or current and conversion ratio of the transformer.
(5) Record the model and rated voltage of the reactor and arc suppression coil.
(6) Check whether the electrical equipment is consistent with the design principle and model.
(Check the model, specification and wiring principle of components and equipment according to the design drawings and data).
(7) The setting value of the equipment shall be subject to the design drawings according to the requirements of Party A.
(8) Check the wire section and the control line connection, both of which should meet the design requirements, and check the contact situation of each connection to ensure that the contact is good.
(9) Various grounding systems and their grounding resistance values should meet the design requirements.
(10) Before commissioning, all system protection devices should be set according to the design value, and their protection, operation and control systems, as well as accident alarm, display and signal systems should be simulated to confirm that they are correct and reliable.
2.10kV busbar
(1) Measure the insulation resistance
Measure the insulation resistance of the bus bar with a 2500V megohmmeter
(2) AC withstand voltage test
Perform AC withstand voltage test with an AC withstand device
3. Oil-immersed transformer
(1) Measure the DC resistance of the winding along with the bushing
Measurements should be taken at all locations of each tap
(2) Measure the transformer ratio of all taps
The transformer ratio of all taps is measured with a ratio bridge
(3) Check the wiring group and polarity
Check the wiring group and polarity with a variable ratio bridge
(4) Insulating oil test
Electrical strength tests are conducted
(5) Check the action characteristics of gas relay and temperature relay
The gas relay presses the test button to check the gas action signal. Check the temperature relay setpoint. Put the thermocouple in the water, heat the water to a little above the set value, and when the water temperature is stable, the
The temperature relay is set according to the set value, and the temperature relay acts.
(6) AC withstand voltage test of winding and casing
Select an AC withstand voltage with the appropriate test voltage and capacity for the withstand voltage test.
4. Vacuum circuit breaker
(1) Measure the insulation resistance
Measured with a 2500 megohmmeter.
(2) Measure the contact resistance of the main contact
The contact resistance of the main contact is measured with a double bridge.
(3) Measure the opening and closing time and synchronicity of the circuit breaker
At the rated operating voltage, it is measured with a high-voltage switching characteristic tester.
(4) Measure the insulation resistance value of open circuit opening and closing
Measure the insulation resistance value of the opening and closing coil with a 500 megaohmmeter.
Measure the DC resistance of the opening and closing coil with a multimeter.
(5) Inspection of the operating mechanism
Use a variable resistor to call up the test voltage and switch operation test.
(6) AC withstand voltage test
The AC withstand voltage test is carried out when the circuit breaker is closed.
5. Current transformer
(1) Measure the insulation resistance
Use a 2500V megohmmeter to measure the primary winding to the secondary winding and the housing. A 500V megohmmeter is used to measure the insulation resistance between the secondary windings and to the housing.
(2) Polarity test
Polarity check is performed using the induction method.
(3) Volt-ampere characteristic curve
The volt-ampere characteristic curve should be measured with voltage and ammeter, which should be above the saturation point. The number of points taken is based on the principle of obtaining a smooth curve.
(4) Variable ratio measurement
A large current is applied on the primary side to measure the secondary current.
(5) AC withstand voltage test
The secondary winding of the current transformer is shorted and grounded, and an AC withstand voltage is used. The primary winding is resistant to the secondary and ground resistance.
6. Voltage transformer
(1) Visual inspection
There should be no obvious damage outside the voltage transformer.
(2) Measure the insulation resistance of the winding
Use a 2500V megohmmeter to measure the primary winding to the secondary winding and the housing. A 500V megohmmeter is used to measure the insulation resistance between the secondary windings and to the housing.
(3) Measure the DC resistance of the primary winding of the voltage transformer
Measured with a single bridge.
(4) Check the wiring group, single mutual inductor polarity.
(5) Check for changes
Measured with a variable ratio bridge.
(6) AC withstand voltage test
The power frequency induction withstand voltage test is carried out with a triple frequency withstand voltage.
7. a reactor
(1) Measure DC resistance
Measure DC resistance with a double bridge
(2) Measure the insulation resistance
Measured with a 2500V megohmmeter.
(3) AC withstand voltage
The AC withstand voltage test is performed using an AC withstand voltage device.
8, Lightning arrester
(1) Measure the insulation resistance
Measured with a 2500 megohmmeter.
(2) Zinc oxide arrester: measure the voltage (V/1mA) value at DC leakage of 1mA and the leakage current at 0.75V/1mA, and measure it with DC leakage tester.
(3) TBP-A or TBP-B type. Measure AC breakdown test.
9. Pillar insulation resistance
(1) Measure the insulation resistance
Measured with a 2500 megohmmeter.
(2) AC withstand voltage test
It is carried out with an AC withstand voltage
10. a capacitor
(1) Measure the insulation resistance
Measuring shunt capacitors is performed between electrode housings.
(2) The AC withstand voltage of the shunt capacitor is the AC withstand voltage of the capacitor electrode to the shell.
11. a power cable
(1) Measure the insulation resistance
Measured with a 2500 megohmmeter
(2) DC withstand voltage test and leakage current measurement
During the test, the test voltage is evenly increased in 4 stages, staying for 1 minute in each stage, and the leakage current value is read.
12. Zero-sequence current transformer
The current value is added once, and the milliampere value is output twice, and the action is fixed to the fixed value.
13. Over-current speed break, voltage, zero sequence protection
(1) Functional parameter setting
(2) Delay protection action test
For time-limited protection, the relay protection test is used to perform the relay action according to the reference value.
(3) According to the reference value, use the relay protection tester to do the relay action test.
(4) Voltage protection
Overvoltage or undervoltage protection.
14. System operation interlocking function test
(1) Interlock test of operation of incoming cabinet and bus unit.
(2) Interlocking test of bus coupling cabinet and isolation switch cabinet.
(3) Interlock test between the incoming line and the PT cabinet.
(4) Test between high-voltage cabinet and transformer.
15. Simulated fault trip test
(1) The display between the operation of the high-voltage cabinet and the signal screen is correct. The smart protector is displayed correctly.
The individual light plates are displayed correctly.
(2) Simulate the overcurrent fault of each feedout circuit, and test the tripping action of each feedout switch.
Power transmission scheme
Fourth, the pre-transmission inspection and preparation
1. All kinds of debugging work of the 10kV power receiving cabinet should be completed before receiving power, and all the power receiving equipment should be in a normal state.
2. Prepare necessary measuring instruments, safety equipment and fire-fighting equipment.
3. Each power receiving cabinet should be equipped with communication equipment, and each power receiving location should be guarded by a special person.
4. The operating mechanism of the handcart cabinet should be flexible, the action should be reliable, and the grounding switch should be in the disconnected position.
5. There should be no loosening in the wiring inspection of the first and second circuits, the operating mechanism is flexible and reliable, and the handcart cabinet is in the test position.
6. Conduct insulation resistance test on the primary and secondary circuits, and the insulation resistance should meet the requirements of the specification.
7. Carry out system tests for control systems, protection systems, and signal systems, simulate various fault signals, relays, and circuit breakers must operate reliably, and signal systems must send out alarm signals.
8. Power can only be received after passing the inspection.
5. Power transmission steps
1. The incoming cabinet trolley and PT (section I) trolley of the section are placed in the working position, and the other feeder trolleys are placed in the test position.
2. The incoming line of section I is powered by section I of the 220kv substation, and the power is checked at the blast furnace 10kv transmission station, or the high-voltage live display should be indicated by a light to confirm that the high-voltage is electrified.
3. After everything is normal, prepare to receive power to the 10kvI section bus.
4. 10kvI section, I section bus is electrified.
Operation: Guardianship:
After everything is normal, measure the PT secondary voltage and phase sequence
| name | OFF | BC | CA | AN | BN | CN | LN |
| voltage |
Phase Sequence: Measurement: Recording:
5. Section II. incoming line cabinet trolley and Section II. PT trolley are placed in the working position, and other feeder trolleys are placed in the test position.
6. Section II. incoming line is powered by the 10 kvII section of the superior 220kv substation, and the power is checked at the blast furnace 10kv substation, or the high-voltage live display should be indicated by a light to confirm that the high-voltage is electrified.
7. After everything is normal, prepare to receive power to the 10kvII. bus.
8. 10kvII. section, II. bus receiving power.
Operation: Guardianship:
After everything is normal, measure the PT secondary voltage and phase sequence
| name | OFF | BC | CA | AN | BN | CN | LN |
| voltage |
Phase Sequence: Measurement: Recording:
9. Nuclear phase test
I. Segment inlet line closure II. Segment inlet denominator joint gate measurement:
| II. Dan I. Dan | A | B | C |
| A | |||
| B | |||
| C |
I., II. incoming line closure, bus coupling measurement
| II. Dan I. Dan | A | B | C |
| A | |||
| B | |||
| C |
Measurement:
Recording:
Wardship:
10. After everything is normal, send the transformer
The first time the transformer is impacted, the current is observed, and the sound of the transformer is opened, if there is any difference, it should be opened immediately, and recorded.
Each time the interval is 5 minutes, a total of five shocks, and after everything is normal, it is put into operation.
6. Instruments for debugging
1. Instruments for insulation protection test
(1) AC test withstand device:
50kv 5kvA一套
200kv 20kvA一套
(2) DC leakage tester:
50kv 1kvA一套
(3) Voltage regulator:
(Single-phase) 0-250v 3kvA per set
(Three-phase) 0-450v 3kvA one
(4) One high-voltage switch characteristic tester
(5) A set of lightning arrester testers
(6) Two multimeters
2. Relay protection test instrument
(1) A comprehensive protection instrument
(2) One voltage regulator (0-250V).
(3) One multimeter
(4) Ammeter
(5) Voltmeter
(6) One current generator
(7) One standard current transformer
Communication: two pairs of walkie-talkies
7. Quality standards
YBJ-89 Metallurgical Electrical Equipment Installation Engineering Construction and Acceptance Specification.
GB50150-91 AC test standard for electrical equipment in electrical equipment installation engineering.
8. Security measures
1. Organize the safety technology disclosure to the participants in the commissioning, so that each commissioning personnel can understand the on-site situation.
2. Commissioning personnel must wear labor protection equipment when entering the site.
3. In the commissioning, it is required to strictly implement safety technology, operating procedures, and obey commands.
4. During the withstand voltage test, the safety equipment should be complete, such as insulating rods, insulating shoes, insulating boots and insulating pads.
5. The cable is voltage-resistant, and the communication at both ends of the cable should be smooth. The test site is fenced, warning signs, and special guards are assigned.
6. When transmitting electricity, the personnel in each position must be clear about their responsibilities and the overall power receiving profile and requirements.
7. The operator must obey the command of the commander and stick to his post.
8. The high-voltage electric detector must be inspected before use, and when used, the electric detector should be gradually moved to the charged body, and should not be in a hurry to contact the voltage.
9. Set up a special person to command, a special person to supervise, a special person to operate, each operation by the commander issued an order, and by the guardian personnel agreed before the operation.
10. Conspicuous signs or fences should be hung on the power transmission equipment.