The heat dissipation index of the air-cooled radiator of a diesel generator set is mainly affected by three aspects such as the heat dissipation area, the thermal conductivity of the material, and the ambient temperature. General material thermal conductivity parameter table The heat sink generally chooses materials with high thermal conductivity, which can help heat dissipation. Generally, the selected materials are silver, copper, aluminum and other materials. The thermal conductivity of these materials can be seen The table shows that copper and silver have high thermal conductivity and strong thermal conductivity, especially silver. The thermal conductivity is twice that of aluminum, which has a very good thermal conductivity, but its cost is too high. For diesel generators There is no need to use it. According to the reference table, aluminum is selected according to the design requirements. Aluminum itself has good mechanical strength, but also has good machinability and thermal conductivity, which can well meet the heat dissipation requirements of silent units. Structural dimensions such as the size and thickness of the radiator
The specific effects of fast start on accelerating the aging of diesel generators include the following aspects: (a) The rapid rise of diesel generators makes the piston ring's force on the cylinder wall and the bearing on the bearing when the normal lubricant film is not completely formed. The load is huge. This metal-to-metal contact can cause wear on the cylinder walls and cam surfaces and accelerate wear on the main and connecting rod bearings. (B) During the rapid acceleration process, the crankshaft without the torsional vibration damping device will produce strong crankshaft torsional vibration. For some diesel engines without torsional vibration dampers, crankshaft cracks appear. The enlarged torsional vibration of the crankshaft is considered to be the cause of this situation. Torsional vibration also occurs in other diesel engine components, such as diesel-driven water pumps, camshafts, and gears. (C) Under the condition that the thermal equilibrium is not reached, the rapid rise of the diesel generator set and the load will cause the cylinder block and the crankcase to undergo high mechanical stress and
According to the analysis of the control circuit of the diesel generator set and the experience of electromagnetic compatibility design, the solutions to the problem of the LED interference of the AC power output indicator of the diesel generator set are as follows: 1. The anti-interference LED indicator with high trigger voltage is selected for diesel power generation. The AC output indicator of the unit is incorrectly indicating the problem. Many manufacturers of power generation equipment believe that the use of a high trigger voltage and strong anti-interference indicator can solve this problem. The internal circuit of this kind of indicator light has been improved. It has an additional threshold circuit than the ordinary indicator light, which increases the threshold voltage of the LED, so that the threshold voltage of the LED is increased from the principle of 3.6V to 30V. Interference problem of AC output indicator of diesel generator set. 2. Series resistance on the indicator light. A resistor is connected in series with the AC power output indicator to divide the voltage, which can effectively reduce the induced voltage of the indicator LED. But if electricity
Recently, Xingguang Company successfully delivered two 120kw Yuchai diesel generating units on the left bank of Evergreen Riverside in Jilin City
Compared with the city power, even the diesel generators with high output power are insignificant. Due to its limited output power capacity, it has adaptive requirements for the input power of the load, the higher harmonic components of the input current, and the input power factor. Otherwise, the electrical equipment and the generator set will be in poor working condition. When the engine generates power with a generator, the three-phase windings in the stator output voltage and current to the load in order of 120 ° electrical angle. In general, when electrical equipment with an input power equivalent to about 60% of the output power of a diesel generator set is connected to the output end of the generator set, it will cause obvious and even strong fluctuations in frequency and voltage. This is because the load needs to input a large current at the moment, which causes the current in the three-phase winding to increase sharply. The strong electromagnetic force generated by this current attracts the rotor of the generator, causing its speed to slow down and the frequency and voltage to drop instantly. It can be seen that when the electrical equipment is connected
The module is divided according to the structural characteristics of the unit to improve the versatility of parts, thereby saving design costs and ensuring the stability of production quality. As the universality of parts is further enhanced, the customer's single order is split into small batches for production, which will increase production efficiency. Because diesel generators have similar structural characteristics, it is relatively easy to divide structural modules. For example, the mute diesel generator set is composed of diesel engine, generator, control panel, water tank, muffler, mute box, shock absorber and chassis (fuel tank) and other components. The unit is divided into modules according to the structure and function of each component. The silent unit is divided into seven functional modules: silent box assembly module, chassis assembly module, power pack assembly module, battery assembly module, control system assembly module, hanger assembly module and muffler system assembly module, and At the time of shipment, some accessories and other components are included, such as
In order to cover the different requirements of each power supply system, the following four types of diesel generator set performance levels are defined: (1) G1 level This class of diesel generator set is suitable for use: only its basic voltage and frequency parameters are required to connect the load. Example: General purpose (lighting and other simple electrical loads) (2) G2 level This class of diesel generator set is suitable for use: its voltage characteristics are very similar to those of public power systems. When the load changes, there may be temporary but permissible deviations in voltage and frequency. Examples: lighting systems; pumps, fans and hoists. (3) The G3 level is suitable for the use of diesel generator sets: the connected equipment has strict requirements on the frequency, voltage and waveform characteristics of the generator set. Example: Telecom and thyristor controlled loads. It should be recognized that load pairs controlled by rectifiers and thyristors
As for the broadcasting stations in large and medium-sized cities, due to the wide radiation coverage, including many branches and branches, the number of diesel generator sets selected is larger. If these units use the same model series, they face a serious problem: monopoly. In the long run, after-sales service cannot be guaranteed. In order to avoid such problems, it is best to use products from several manufacturers. This promotes healthy competition among manufacturers. Those who have good product quality and better after-sales service will be more likely to be selected. Otherwise, they will be eliminated and the selection initiative will be controlled by various broadcasting stations. For the broadcasting stations in suburban counties and remote areas, generally equipped with a diesel generator set can meet the working requirements. When working with a single diesel generator set, more consideration must be given to the stability and quality control of the unit. In addition, manufacturing diesel generator sets is a mature technology. The equipment produced by domestic manufacturers is the same as the equipment produced by foreign manufacturers.
The effective adjustment of the rotational speed can ensure that even when the external load fluctuates or changes greatly during operation, the diesel generator set can adjust the fuel supply of the injection pump to ensure the stability of the rotational speed. So the solution to the stability of the diesel generator set is the governor with excellent performance.
Torsional vibration is an inherent characteristic of marine diesel generator sets. When the initial interference torque is applied to the shafting, the shafting will produce a periodically changing torsional elastic deformation motion, that is, torsional vibration. If there is no damping in the shaft system at this time, this torsional vibration will continue to be repeated, which is called undamped free vibration. Appears as the natural frequency of various modes. When the unit is running, the shaft system is stimulated by the gas force of the diesel engine cylinder and the reciprocating inertia force of the piston link mechanism. When the frequency of some simple harmonic components in the excitation torque is equal to or close to the natural frequency of the shaft system torsional vibration, the shaft system torsional vibration The amplitude will increase sharply, and the torsional vibration stress will also increase significantly. This phenomenon is called the shaft torsional vibration resonance. Severe primary harmonic torsional resonance can cause serious damage to the shaft system or even break the shaft. Shaft torsional vibration mode is the most intuitive manifestation of the torsional vibration of the diesel generator set shaft system. The shaft section where the node appears, especially the two ends of the shaft section are concentrated.