1. The generator stator voltage should not be higher than the rated voltage (110%), the minimum voltage should not be lower than the rated voltage (90%), and should meet the (factory) voltage requirements.
2. The normal running frequency of the generator should be kept at (50) Hz, the allowable variation range is (±0.2) Hz, and it can be continuously operated according to the rated capacity. When the frequency changes, the stator current, excitation current and temperature of each part shall not exceed (rated value).
3. The generator stator voltage is allowed to fluctuate within the rated value range (±5%). When the power factor is rated, its rated capacity does not change, that is, when the stator voltage fluctuates within this range, the stator current can be changed proportionally. . However, when the generator voltage is lower than the rated value (95%;), the long-term allowable value of the stator current shall not exceed the rated value (105%.).
4. The hydrogen purity of the generator operation shall not be lower than (96%), and the oxygen content shall be less than (2%). 
5. The rated power factor of the generator is (0.85). Generators that have not been subjected to the phase-in-phase test, when the excitation regulator device is automatically activated, the power factor is allowed to operate for a long period of time in the range of 0.96 to 1; when the power factor is changed, the power factor should be The power of the power does not exceed the range of the (PQ) output curve at the time of hydrogen pressure.
6. After the generator is juxtaposed, the active load increase speed is determined by (turbine), and the reactive load increases speed (not limited), but the stator voltage change should be monitored.
7. The insulation resistance of the generator rotor winding is measured with a (500V) shaker. The insulation value shall not be less than (0.5MΩ).
8. When the three-phase current of the stator is unbalanced, a (negative sequence) current will be generated.
9. During the boosting process, the generator should check that the three-phase voltage of the stator should rise (smoothly) and the rotor current should not exceed (no-load value).
10.6KV motor measurement insulation should be measured using a (2500V) volt table, and the measured insulation resistance should be greater than (6) MΩ.
11. Under normal conditions, the motor of the squirrel-cage rotor is allowed to start in the cold state (2 times), and each time interval is not less than (5) minutes, allowing to start (1) times in the hot state, only in the accident Motors that have been processed or started for less than (2 to 3) seconds can be started more often.
The insulation resistance of the motor of 12.6KV high voltage factory is measured under the same environment and temperature. If the current measurement is lower than (1/3~1/5) times of the previous measurement value, the cause should be checked and the absorption must be measured. This value should be greater than (1.3) than "R60/R15".
13. The motor can be operated within the rated voltage and the power frequency (±l%), and its rated output is unchanged.
14. The main transformer cooler (full stop) is allowed to operate at the lower limit of the rated load. If the load is small, the main transformer upper oil temperature does not reach the specified value, and it is allowed to rise to the specified value, but the longest running time of the main transformer must not exceed (60). )minute.
15. The three-phase unbalance current of the AC motor must not exceed the rated value (10%), and the current of any one phase must not exceed (rated value).
16. For oil-immersed self-cooling and oil-immersed air-cooled transformers, the maximum allowable oil temperature of the upper layer shall not exceed (95) °C, and generally should not exceed (85) °C.
17. When the gas protection secondary circuit is grounded at one point, the heavy gas protection should be changed to the (signal) position.
18. The temperature of the upper layer of the transformer that forces the oil circulation to be air-cooled generally does not exceed (75) °C, and the maximum does not exceed (85) °C.
19. The transformer is applied with a primary voltage, generally not exceeding the rated value of the tap (105%). At this time, the secondary side of the transformer can be rated current.
20. The general power plant adopts double busbar wiring. During normal operation, one component (grounding) should be guaranteed on each entry line. The main transformer is generally grounded (grounded blade), and the neutral point is normally (directly) grounded.
21.6KV switchgears are equipped with "five-proof" mechanical locking devices. Generally, the locking function of the forced mechanical locking device is (the trolley switch cannot be moved when it is closed). (When the grounding knife is closed, the trolley switch Can not be pushed into the working position), (when the switch is in the working position, the grounding knife can not be closed), (the grounding knife does not close, can not open the back panel of the switch cabinet).
22. After all the isolating switches are closed, the contact (three-phase contacts) must be in good contact.
23. Before closing the grounding switch, it must be known that the power switch on each side is in the (disconnected) position and after the verification (no voltage).
24. If a load-carrying broach is generated, it should be quickly (closed) before the arc is broken. If the arc is broken, it is forbidden to re-close. If the load is closed, it is forbidden to restart (disconnect).
25. When no switch is provided in the circuit, the isolation switch can be used to perform loop equalization current with the pull-in voltage not exceeding 10KV and the current below (70A).
26. The normal operating voltage of the cable line shall not exceed (15%) of the rated voltage of the cable.
27. Under normal circumstances, electrical equipment is not allowed to operate (no protection). If necessary, partial protection can be deactivated, but (main protection) is not allowed to be deactivated at the same time; it is forbidden to open the protection cabinet door during operation, and it is forbidden to continue in the centralized control room. Guaranteed indoor use (wireless) communication equipment.
Insulation resistance is measured by a (500) V shaker for AC and DC low voltage factory motors below 28.380V. The insulation resistance of the motor must not be less than (0.5) MΩ.
29. Generator definite time overload protection reflects the size of the generator (stator current).
30. The overvoltage protection of the generator stator winding reflects the magnitude of the (terminal voltage).
31. Generator Timing The negative sequence overcurrent protection reflects the size of the generator stator (negative sequence current) and prevents the generator (rotor surface) from overheating.
32. The four limiting factors on the PQ curve of the generator are (heating of the stator winding, heating of the rotor winding, heating of the iron core at the end of the stator, stable operating limit).
33. Generator reverse power protection for protection (turbine).
34. The order of installing the grounding wire is first (grounding) and rear (conductor).
35. Electrical insulation materials are graded according to their maximum working temperature (temperature) under normal operating mode.
36. The current value indicated by the AC ammeter indicates the (effective) value of the current.
37. The safety distance of equipment without power failure is (0.7)m for 6kV, (1.5)m for 110KV, and (5)m for 500KV.
38. In a power plant, the phase sequence of the three-phase busbar is represented by a fixed color, and the (phase), phase B, and phase C are specified by (yellow), (green), and (red), respectively.
39. The equipment ground voltage is below (250) volts for low voltage equipment, so we often say that the 380V plant power system is (low voltage equipment).
40. When the generator is in normal operation, the three-phase unbalance value of the stator current generally cannot exceed the rated value of the stator (10%).
41. The operation of phase differential high frequency protection uses a (high frequency) signal to compare the current (phase) across the protected line.
42. When the isolating switch is found to be hot, the equipment (load) should be lowered until it does not heat up, and the ventilation and cooling of the device should be strengthened. If the heat is severe, it should be stopped (stop) after the equipment is operated.
43. When the temperature difference between the highest and lowest temperatures between the stator bars of the water-cooled generator is (8) °C or the temperature difference of the stator bar water pipe is (8) °C, the alarm should be reported and the cause should be ascertained. Reduce load) processing.
44. The temperature difference between the stator bars of the water-cooled generator is (14) °C or the temperature difference of the stator inlet pipe is (12) °C, or the temperature of the temperature measuring component in any stator slot exceeds (90) °C or the outlet temperature exceeds ( 85) At °C, after confirming that the temperature measuring component is correct, in order to avoid a major accident, it should be immediately (stopped), (backwashing) and related inspection processing.
45. The product of the rms value of the total voltage in the sinusoidal AC circuit and the rms value of the current, both (active power) and (reactive power), we call it (apparent power).
46. ​​In a circuit, the current flowing into the node (equal to) the current flowing from the node, which is Kirchhoff.
47. Starting from any point in the loop, one cycle along the loop, the sum of the potential rises (equal to) the sum of the potential drops, which is Kirchhoff (second law).
48. In the various methods of calculating complex circuits, the (branch current) method is the most basic method.
49. In an (inductive) circuit, the voltage leads the current; in a (capacitive) circuit, the voltage lags the current.
50. In power systems, a shunt reactor is commonly used to absorb excess (reactive) power and reduce (system voltage).
51. In a three-phase AC circuit, a delta-connected power supply or load, their line voltage (equal to) phase voltage.
52. The total power of a symmetrical three-phase AC circuit is equal to (3) times the single-phase power.
53. For a symmetric three-phase AC circuit, the neutral point voltage is equal to (zero).
54. In a power system, a short circuit is an abnormal connection between (phase and phase) or (phase to ground) through an arc or other lesser impedance.
55. A battery is an energy storage device that converts (electrical) energy into (chemical) energy storage; in use, it converts (chemical) energy into (electrical energy) and is released through an external circuit.
56. The size of the conductor resistance is related not only to the (length) and (cross-sectional area) of the conductor, but also to the (material) and temperature of the conductor.
57. In a closed circuit, the voltage is a condition for generating a current, and the magnitude of the current is related to both the (resistance) magnitude of the circuit and the magnitude of the (terminal voltage).
58. In a series circuit, the voltage distribution across the load is proportional to the magnitude of each load resistor; in a parallel circuit, the distribution of each branch current is inversely proportional to the resistance of each branch.
59. When the (current) in the coil changes, the (self-inductance) electromotive force is generated at both ends of the coil.
60. After the conductor is energized, the direction of the electromagnetic force received in the magnetic field is determined by (left-hand rule), and the direction in which the induced electromotive force is generated when the conductor is subjected to the cutting magnetic field in the magnetic field is determined by (right-hand rule).
61. The number of periodic changes in alternating current per second is called (frequency), represented by the letter (f), the unit name is (hertz), and the unit symbol is expressed in (Hz).
62. The maximum instantaneous value of a sinusoidal alternating current in a cycle is called the (maximum) value of the alternating current, also known as (amplitude) or (peak).
63. The maximum value of the rms value of the alternating current is divided by (√2).
64. In a circuit composed of a resistor, an inductor, and a capacitor, only a (resistive) component consumes power, and an (inductor) component and a (capacitor) component exchange energy without consuming power.
65. The power supply mode of the star connection not drawn at the neutral point is (three-phase three-wire) system, and the current relationship is that the line current is equal to (phase current).
66. The greater the current through a coil, the stronger the (magnetic field) produced, the more (magnetic) lines that pass through the coil.
67. The current-carrying coil can generate a magnetic field, and its (strong) is in a (proportional) relationship with the magnitude of the current through the current-carrying conductor.
68. The voltage between the three-phase end lines is called (line voltage); the voltage between the end line and the neutral point is (phase voltage); in a symmetric circuit with a star connection, the line voltage is equal to (√3) times the phase Voltage.
69. The main cause of short circuit in the power system is that the (insulation) of the current-carrying part of the electrical equipment is destroyed.
70. Short-circuit damage to electrical equipment mainly includes: (1) current (thermal effect) causes equipment to burn or damage insulation; (2) (electric power) causes electrical equipment to be deformed and destroyed.
71. Electrical equipment and current-carrying conductors must have sufficient (mechanical) strength to withstand the electrodynamic forces of short circuits and adequate thermal (stability).
72. Transformer is based on (electromagnetic induction) principle, the voltage and current of an alternating current become the same (frequency) but different (value) voltage and current.
73. The principle of induction motor is that when three-phase is set in the winding, a three-phase symmetrical alternating current flows, and a (rotating) magnetic field is generated. The magnetic field line of the magnetic field cuts the wire on the rotor to induce (current), because the stator magnetic field interacts with the rotor current. Produce electromagnetic (torque) and turn it up.
74. Both the copper wire and the aluminum wire are connected by a conversion joint. If they are directly connected, the copper and aluminum wires have a potential difference. If there is moisture in the joint, the formation of (ionization) and electro-corrosion occurs.
75. In the vicinity of the transmission line, if an insulator is placed, an (inductive) charge is generated. This phenomenon is called (electrostatic) induction of the transmission line.
76. Sulfur hexafluoride (SF6) is a (colorless), (odorless) non-combustible gas with very stable properties.
77. The battery is used as a (control) and (protected) DC power supply in the power plant, which has the advantages of stable voltage and reliable power supply.
78. The active material on the (positive) plate of the battery is lead dioxide, and the active material on the (negative) plate is spongy lead.
79. The capacity of a group of batteries is 1200AH. If it is discharged at a current of 100A, the continuous power supply time is (12 hours).
80. Under normal circumstances, electrical equipment only bears its (rated) voltage. Under abnormal conditions, the voltage may rise more and the voltage that is dangerous to the insulation of electrical equipment rises. We call it (overvoltage).
81. In the power system, the external overvoltage is also called (atmospheric) overvoltage, which can be divided according to the form of overvoltage: (direct) lightning overvoltage, (inductive) lightning overvoltage.
82. In the power system, the internal overvoltage can be divided into: (operation) overvoltage, (arc grounding) overvoltage, (electromagnetic resonance) overvoltage.
83. Megger terminals have three L, E, G, which mean: L (line), E (ground), G (shield).
84. When measuring the insulation resistance of electrical equipment, the insulation is generally judged by the absorption ratio. When the absorption ratio is greater than 1.3, it means (insulation is good); when it is close to 1, it means (insulation is damp).
85. The multimeter's meter head is the main component of the multimeter. It is a high-sensitivity (magnetoelectric) type DC (current) meter.
86. The purpose of the circuit breaker is to enable (turn on) or (disconnect) the circuit when it is normal; to automatically (cut off) the fault current when a fault occurs, and to automatically (coincident) when necessary, to play both control and protection. .
87. The role of the oil in the circuit breaker is (arcing) and (insulating).
88. The function of the high-voltage isolating switch is: (1) turn on or off (allow) the load circuit; (2) cause an obvious (open) point to ensure personal safety; (3) cooperate with (breaker) switching Operation mode.
89. The insulation of the high-voltage isolating switch mainly includes: (grounding) insulation; (fracture) insulation.
90. The primary wiring of the power plant should meet the requirements of (safe) reliability, (method) flexibility, and (overhaul) convenience.
91. The secondary rated voltage of the voltage transformer is generally (100)V, and the secondary rated current of the current transformer is generally (5)A.
92. Insulating materials have good (dielectric) properties, ie high (insulation) resistance and compressive strength.
93. People classify substances in nature as (conductors), (semiconductors) and (insulators) according to their conductivity.
94. When the charged bodies are close to each other, they will have a powerful effect. When the objects with the same charge are close to each other, the action is (mutually exclusive); when the objects with the opposite charge are close to each other, the action is (attractive to each other).
95. When two coils respectively flow or flow current from a fixed end, the (magnetic flux) generated by them is mutually enhanced, and the ends are said to be (same name) ends.
96. Capacitive components exhibit a very small capacitive reactance to (high-frequency) currents, while pairs (DC) can be considered as open circuits, so capacitors have a (straight-straight) effect in the circuit.
97. The unit of active power is used (watts), the unit of reactive power (fail), and the unit of apparent power (volt-amperes).
98. In a single-phase circuit, the apparent power is equal to the product of the (voltage) and (current) rms values.
99. In order to increase the cross-section current of the busbar, the number of parallel busbars is usually used to solve, but the more the number of parallel bars, the more (uneven) the current distribution, the current flowing through the intermediate busbar (small), flowing through the busbars on both sides. Current (large).
100. Circuit breakers can be divided into: (gas) dielectric circuit breakers, (liquid) dielectric circuit breakers, (vacuum) circuit breakers, etc. according to the arc extinguishing medium.
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