Common faults and measures of box-type substation

Common faults and measures of box-type substation

1.Heat treatment measures for box change. Overheating of electrical equipment in box-type substations can easily lead to insulation degradation and loose joints for a long time. The internal short circuit of the box-type substation will also increase the temperature and even cause a fire. Transformer windings are also prone to heat during operation, and continuous heat can easily damage the transformer. In view of the overheating of the box-type substation, it is necessary to clean up the residual materials inside the box-type substation, such as dust, etc. The second is to strengthen the temperature monitoring of each equipment in the box change, and send out high temperature warning signals in time.

2. The on-load switch of the box substation is faulty. Except for its own failure, the on-load switch in the box-type substation rarely fails. The failure of the on-load switch is mainly due to the following reasons: First, the switch has been used for a long time, and the switch frame is deformed, causing the switch to loosen and fall off; the second component is not strong enough to cause the tap switch to be damaged during the switching operation; The third is that the quality of the switch is not up to standard, and the spindle breaks after a period of use. In order to ensure the stable operation of the box substation, the on-load switch must be strictly selected during the production process to ensure the quality of the switch and the installation process.

3. The low-voltage switch of the box substation has tripped failure. There are two main factors for the tripping of the low-voltage switch of the box substation. One is the bus failure; the other is the switch malfunction. In the event of a low-voltage switch trip failure, the box-type transformer needs to be carefully inspected. Once over-current protection occurs on the low-voltage side of the main transformer, the relevant equipment needs to be inspected and protected immediately. At the same time, eliminate the malfunction of the switch and focus on whether it is a bus failure or a line failure. Further check the related equipment, check whether the protective plate of the used equipment is missed, and if necessary, take professional equipment inspection.

Inspection and repair of tripping faults in box-type substations

1. Box-type substation operation stage trips mainly include main transformer switch tripping and line switch tripping. The main transformer switch tripping is divided into three-side tripping fault of main transformer and low-voltage side tripping fault of main transformer. Judging what causes the transformer trip of the box-type substation mainly depends on various monitoring data analysis.

2. When the outdoor box-type substation has a trip failure, the maintenance personnel must rush to the scene as soon as possible and restore the power as soon as possible. The maintenance personnel first check whether the equipment is seriously damaged, and then check the working conditions of the trip switch and the arc suppression coil. For spring energy storage switches, check whether the spring energy storage fails, and for electromagnetic switches, check the switch power insurance.

3. When the low-voltage trip of the main transformer of the box-type transformer fails, check the line protection and main transformer protection in the substation equipment to find the cause of the accident. When the overcurrent protection on the low-voltage side of the transformer is the only cause of failure, the line fault can be eliminated, the output terminals should be checked, and then the substation equipment should be checked. When the overcurrent protection on the low voltage side of the transformer also has line protection, it can be directly determined as a line fault according to whether the line is broken. The maintenance personnel should not only check the line outlet position, but also check the entire line to eliminate the line fault After that, the switch trip fault processing can be performed.

Precautions for fire-proof and explosion-proof operation of box-type substations

1. Box-type substations cannot be overloaded for a long time, especially after a few years of use, you must start to pay attention to problems such as coil aging and insulation aging to prevent short circuits.

2. If an oil-immersed transformer is installed in a box-type substation, the insulation performance of the transformer oil should be checked regularly, and the unqualified ones should be replaced in time.

3. During the operation of prefabricated substations, the operating conditions of the transformer should be monitored at any time to prevent long-term heat generation of the transformer core and cause insulation aging, and care must be taken not to damage the insulation layer during maintenance.

4. Pay attention to wire contact problems during daily maintenance of box-type substations, and deal with poorly contacted wires in time.

5. The high-voltage switchgear, transformer, and low-voltage switchgear of pre-installed box-type substations will be equipped with lightning arresters, the purpose is to prevent lightning strikes from damaging related equipment and protect the safe operation of box-type substations.

6. In the design stage of the box-type substation, it is necessary to consider the ventilation and heat dissipation, and design enough vents and exhaust fans. Ziguang box-type substation is equipped with exhaust fans in the transformer and low-voltage rooms. The transformer room has an automatic temperature monitoring system that can be effectively controlled. Temperature inside the box-type substation.