Maintenance of Diesel Generators for Communication Systems

Maintenance of Diesel Generators for Communication Systems

Abstract: Correct maintenance and maintenance of diesel generators will ensure that the performance of diesel generators is in good condition to ensure safe and reliable power supply for communication networks. The article describes the daily maintenance and maintenance of diesel generators.

1 Introduction

The diesel generator set is the backup power source for the communication system and its main function is to provide power when the utility power fails. In fact, the diesel generator set is in standby mode most of the time, and there is less opportunity for actual use. However, the diesel generator is an indispensable emergency power supply device and can play an important role in critical moments. If the load capacity and various electrical characteristics of the diesel generator set do not meet the communication power requirements, normal power supply will not be provided, which will result in communication interruption. Therefore, to ensure that the diesel generator set can be powered on in a timely manner and that the diesel generator set can be powered in a timely manner, the diesel generator set must be properly maintained and maintained.

2. The composition and characteristics of diesel generator sets

2.1 The composition of the diesel generator set

The diesel generator set consists of three parts: diesel engine, three-phase AC synchronous generator and control panel.

A diesel engine is an energy conversion device that converts thermal energy released by the combustion of fuel into mechanical energy. The diesel engine is the power part of the generator set. It is generally composed of a crankshaft linkage mechanism and body components, a valve distribution system and an intake and exhaust system, a diesel supply system, a lubrication system, a cooling system, and an electrical system.

The generator is mainly composed of a stator, a rotor and an end cap. Usually the armature winding of the three-phase AC synchronous generator is connected with the three-phase power supply circuit, and the excitation winding is connected with the DC power supply. In order to facilitate the introduction or withdrawal of armature currents, large and medium-sized synchronous generators generally adopt a rotating magnetic pole structure. Synchronous generator main salient pole and hidden pole two kinds of magnetic circuit structure.

The generator control (screen, box) system is the unit's supporting equipment, including automatic detection, control and protection devices. It is mainly responsible for the control, pressure regulation and power distribution of the unit. The unit supplies power to the electrical equipment through the control panel. At the same time, the operator can directly observe the operational status of the unit from the control panel. The excitation adjustment and control parts of the general small-capacity generating units are all concentrated in the control box and directly installed in the unit. The control screen of the large-capacity generator is floor-standing and is fixed on the ground of the equipment room or installed in the centralized control room isolated from the unit. .

2.2 Characteristics of Diesel Generators

(1) There are many stand-alone capacity levels, and the range of available capacity is large, which has the advantage of being suitable for a variety of capacity power loads.

(2) The supporting equipment has a compact structure and a flexible installation site.

(3) High thermal efficiency and low fuel consumption. The effective thermal efficiency of a diesel engine is 30-40%, and the fuel consumption is generally 0.23-0.26kg/KWh.

(4) Start quickly and achieve full power soon. The start-up of a diesel generator typically takes only a few seconds and can be brought to full load within 1 min under emergency conditions and brought to full load within about 5-30 min under normal operating conditions.

(5) The maintenance operation is simple, the number of operators required is small, and maintenance during the standby period is easy.

(6) The overall cost of the diesel generator set and generator is low.

3, diesel generator check before start

(1) Whether the oil level of the oil and cooling water meets the specified requirements. The oil level should be between the high (H) and low (L) markings of the oil dipstick. The engine oil should be replenished after 15 minutes of shutdown. The cooling water level should be below the neck of the expansion tank plus the water neck. The open circulation cooling system should be used. Water should be turned on.

(2) Whether the air inlet and exhaust air ducts are open.

(3) Check the amount of fuel in the daily fuel tank, and check whether the oil inlet and return oil lines are unobstructed.

(4) Check whether the electrical starting system is connected correctly, whether it is loose, and whether the starting battery voltage and liquid level are normal.

(5) Clean up the unit and nearby tools, parts and other items to avoid accidents when the unit is running.

(6) When the ambient temperature is lower than 5°C, the unit should be heated before starting up.

4, diesel generator start, running check

(1) Whether the oil pressure, oil temperature, and water temperature meet the requirements of the specification.

(2) Whether various meter indications are stable and within the specified range.

(3) Whether each signal indicator is normal or not.

(4) Cylinder work and exhaust smoke are normal.

(5) Whether there is severe vibration and abnormal sound when the oil machine is running.

(6) The voltage and frequency (rotational speed) can reach the specified requirement and operate stably after power supply.

(7) Whether the system has low-frequency oscillation after power supply.

(8) The starter temperature rise should not be too high, and the flywheel window should not have continuous sparks.

5, diesel generator shutdown

(1) Normal shutdown: When the utility power is restored after the power supply or testing is completed, the load is cut off first, then the throttle stop is stopped after idling for 3 to 5 minutes. After parking in winter or in cold areas, open the drain valve of the freshwater pump oil cooler (or u-shaped cooling pipe) and the radiator, etc. on the side of the machine, and let the cooling water to prevent freezing. If antifreeze is used, it is not necessary. Let go.

(2) Fault shutdown: When there is a low oil pressure, high water temperature, high speed, abnormal voltage, etc., it should be able to stop automatically or manually.

(3) Emergency stop: When the speed is too high (speed) or other personal accidents or equipment hazards occur, the emergency shutdown of the oil and air intake lines must be immediately stopped.

(4) After failure or emergency shutdown, check and record shall be made. The unit may not be restarted when the unit has not been removed from the fault and returned to normal.

6, diesel generator maintenance

(1) Check the meter. Observe that the reading is normal, otherwise repair or replace it in time.

(2) Check whether the start, cooling, lubrication, fuel, and ventilation systems are normal.

(3) Clean the air filter. The steel wool is taken out and cleaned in gasoline, and the compressed oil is washed with compressed air, and an appropriate amount of new engine oil is added.

(4) Clean the cooling water radiator. Rinse the radiator with clean water and remove the deposits until it is clean.

(5) Check the sealing of the intake and exhaust valves. Remove the cylinder head, observe the sealing and wear of the fitting taper, and polish and repair if necessary.

(6) Clean the oil and fuel system piping. Including cleaning oil sump, oil pipe, oil cooler, fuel tank and its pipes, remove dirt and blow dry.

(7) The three filters (oil filter, diesel filter and air filter) and oil must be replaced regularly as required by the instructions.

(8) Check the start battery. The positive and negative terminals of the start battery are often oxidized by the acid, so they should be cleaned in time to prevent the unit from starting. If the battery is used for a long time, the capacity will be reduced. When the capacity is reduced to 80% of the rated capacity or the unit cannot be started, the battery should be replaced. It is recommended that the battery be replaced every 2 years.

7. Conclusion

The power supply is the "heart" of the communication system. The diesel generator is the backup power source in the communication system. Its performance and running quality are directly related to the safe and reliable operation of the communication network. Therefore, we must pay attention to details, pay attention to specifications, and do a good job of routine maintenance and maintenance work to ensure that diesel generators are readily available and provide safe and reliable power for communication networks.