How To Maintain A Wide Range Voltage Stabilizer

Wide Range Voltage Stabilizer is one of the most common power equipment in the distribution network. It is also the most contacted power equipment in the basic management work. Let's talk about the experience of wide-range voltage stabilizer maintenance.

1. Strengthen daily inspection, maintenance and regular testing

Key inspection contents include:

(1) Look at the appearance. First of all, check whether there is oil leakage on the outside of the wide-range voltage stabilizer, whether there is smoke or discharge from the parts. Because the wide-range voltage stabilizer shell is not tightly welded or the rubber pad is not solid, it may cause the wide-range voltage stabilizer to leak oil. If the oil level is too low, it will lose insulation protection, resulting in discharge between the conductive parts or between the conductive parts and the shell. In severe cases, the wide-range voltage stabilizer will be burned. Therefore, the fault should be eliminated and the oil should be replenished in time to ensure that the oil level is maintained at 1/4-3/4 of the oil mark. For loose parts, poor contact or even discharge, the wide-range voltage stabilizer should be disconnected and secured in time to eliminate hidden dangers.

(2) Listen to the sound. A wide-range voltage stabilizer in normal operation will emit a uniform and subtle humming sound. When a wide-range voltage stabilizer has a fault of different nature, the sound will change. At this time, measures should be taken according to the on-site situation to find the cause of the fault.

(3) Check the oil stains on the distribution transformer and the dust on the high and low voltage bushings, and clean and wipe the oil stains and dust in time to prevent flashover discharge in humid or rainy weather, resulting in short circuit between bushings, high-voltage fuses blowing, and distribution transformers failing to operate normally. Our institute requires inspection personnel to clean at least once every two months.

(4) Observe the oil color and regularly check the oil temperature, especially in weather with large load changes, large temperature differences, and severe weather, increase the number of inspections. The top oil temperature of the oil-immersed distribution wide-range voltage stabilizer during operation shall not be higher than 95°C. In order to avoid excessive deterioration of the windings and oil, the temperature rise of the top oil should not often exceed 45°C.

(5) Shake and test the insulation resistance of the distribution transformer to check whether each lead is strong. Pay special attention to whether the low-voltage outlet connection has good contact and abnormal temperature.

(6) Strengthen the measurement of power load. During the peak period of power consumption, strengthen the load measurement of each distribution transformer. If necessary, increase the number of measurements. Adjust the wide-range voltage stabilizer with unbalanced three-phase current in time to prevent the neutral line current from burning out the lead, causing damage to user equipment and distribution transformer. For distribution transformers with connection group Yyn0, the three-phase load should be as balanced as possible. Only one or two phases should not be used for power supply. The neutral line current should not exceed 25% of the rated current on the low-voltage side. Strive to ensure that the distribution transformer is not overloaded or unbalanced.

(7) Check and replace primary and secondary fuses regularly. It is strictly forbidden to replace safety wires with aluminum wires. As we all know, primary fuses have a protective effect on the system, and secondary fuses have a protective effect on wide-range voltage stabilizers. The selection of fuses must be adapted to the capacity of the voltage stabilizer.

2. Avoid external force damage:

(1) Choose the installation location of the distribution transformer reasonably, and try to get the installation location close to the load center, and control the power supply radius within 0.5km. At the same time, try to avoid installing it in areas that are prone to lightning strikes or low-lying waterlogging. Because it is located in the county town, there are many voltage stabilizers at the intersection. In order to reduce the accident of cars hitting the pole towers, anti-collision strips are posted on all the pole towers along the road.

(2) Try to avoid installing low-voltage meter boxes on the distribution voltage stabilizers. Due to long-term operation, the glass of the meter box is damaged or the low-voltage pile head of the distribution transformer is damaged and cannot be replaced in time, resulting in the burning of the energy meter due to rain and other reasons, causing damage to the distribution transformer. More than 95% of our shared distribution transformers are all installed in JP cabinets, which has a good protective effect on the safe operation of the voltage stabilizer.

(3) It is not allowed to adjust the tap changer privately to prevent the tap changer from being adjusted in place and causing phase short circuits, resulting in burning of wide-range voltage stabilizers.

(4) Install insulation covers at the high and low voltage ends of the distribution transformer to prevent damage from natural disasters and external objects. Install high and low voltage insulation covers in communities with narrow roads and forest areas where animals frequently enter and exit to prevent objects from falling on the wide-range voltage stabilizer terminal posts and causing low-voltage short circuits and burning distribution transformers.

(5) Regularly inspect the lines and cut down the line channels to prevent branches from hitting the wires and causing low-voltage short circuits and burning distribution stabilizers.