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
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 recent years. A large number of diesel generator sets are equipped on newly-built air-conditioning generator cars. With the increase of applications, the fire danger caused by them is gradually increasing. Therefore, the most urgent task is to carefully find and analyze the fire hazards existing in the diesel generators of power generators in combination with the use, maintenance and use of the situation, and put forward preventive measures. Potential fire hazards in diesel generator sets (1) Leakage of fuel from the pipes of the body accumulates for a long time, and it is easy to smoke and catch fire at high temperatures. (2) The quality of the high-pressure oil pipe and the fittings of the oil pipe are not good, which may cause the fuel to be sprayed outward to the high-temperature turbocharger or the exhaust pipe. (3) Fires caused by abraded short circuits or loose wiring may ignite high temperature atomized fuel. (4) Incorrect adjustment of the intake valve, exhaust valve, and fuel injection advance angle of the diesel engine, the joint between the cylinder head and the body or the exhaust pipe is not tight, which can cause high temperature and high pressure fuel to not be completely burned in the cylinder, and the joint is injected Combustion and fire.
Diesel generator sets generate high temperature due to the combustion of diesel during operation. In order to ensure that the heated parts of the diesel generator set and the shell of the supercharger are not affected by high temperatures, and to ensure the lubrication of each working surface, it is necessary to cool the heated parts.
In order to complete the power supply for the diesel generator set, in addition to the unit itself, the power distribution system, parallel system and related control accessories are required to work normally and reliably. All links are more important, otherwise they may fail. Unable to complete emergency power supply. For example, the parallel operation of diesel generator sets requires the cooperation of related control cables, relays, and contactors. In a humid environment, the relays and contactors may appear rusted and adhered, and may fail during real use, or even control line connections. Looseness and fall-off may cause failure to achieve parallel operation. Therefore, daily inspections should pay attention to check whether the related accessories of the diesel generator set work normally, whether the knob is in the correct position, pay attention to every detail, and find out the hidden dangers and deal with it in time. The monthly test machine also directly adopts the parallel test machine in order to find out in time whether there is a problem with the related accessories of the parallel system. Do a good job of maintaining the diesel generator set.
A diesel engine is an important part of a small diesel generator set. Once a diesel engine fails, it will greatly affect the normal operation of the generator set. Therefore, it is very important to research and analyze the common faults of diesel engines. Under normal circumstances, the failure of the diesel engine part is as follows: ① The air filter is blocked. The air filter is an important component to ensure that the intake and exhaust valves of the diesel engine are unobstructed. However, after the diesel engine is used for a period of time, the air filter is likely to become clogged, causing the intake and exhaust valves to be blocked and the diesel engine to emit black smoke , Can not start normally. This requires cleaning or replacing the air filter of a small diesel generator set that has been used for a long time. ② Diesel engine oil pipe is blocked. The fuel pipe is a device that guarantees the smooth fuel supply of the diesel engine. If the fuel pipe or the diesel filter is blocked, it will affect the fuel supply and cause the diesel engine to fail to start normally. At this time, the tubing should be cleaned or replaced. ③
The electronic governor and the generator form a closed-loop speed control system. Its stability depends on factors such as generator inertia, system time constant, engine link gain, governor link gain, and disturbance. The stability adjustment range of any closed-loop control system, if it exceeds the stability range shown in the figure, the system is unstable. In the stability domain diagram, the diesel generator set can run stably when the differential and gain are in the shaded area. If it is less than the low gain stability line, the diesel generator set will run at low frequency; if it crosses the high gain stability line, the diesel generator set will run at high frequency Cruise. Under the premise of ensuring that the system has a certain stability margin, the differential and gain should be close to the high-gain stability line to ensure that the electronic governor has excellent dynamic and steady-state speed regulation indicators. For stability adjustment, you need to adjust the gain and differential (stable) potentiometer. Adjust the gain potentiometer to adjust the sensitivity of the system to obtain a suitable transient response
The on-site verification device for diesel generator set output characteristics mainly consists of hardware and software. The system is mainly composed of AC electronic load module, power acquisition module, temperature acquisition module, data processing software and human-computer interaction system. The block diagram of the system is shown in the figure. The main working process of the system is: 1) After the system is powered on, the user sets the AC electronic load to output the simulated load through the touch screen input according to the test and detection needs. The embedded computer sends instructions to the AC electronic load through the serial port to control the AC electronic load. Output resistive load. 2) The power collection module collects the three-phase voltage, three-phase current, and frequency and other related information output by the diesel generator set under test in real time. After analog-to-digital conversion, the analog quantity is converted to digital quantity and sent to the embedded computer via the serial port. 3) The temperature acquisition module collects the system ambient temperature in real time. After analog-to-digital conversion, the analog value is converted into a digital value and sent to the embedded computer via the serial port.
The diesel generator set running in parallel is an important operating state. Taking the ship operation industry as an example, when a ship ’s power grid has a large amount of power consumption or the ship is docked at a dock or a narrow waterway, it will start a second or more diesel generators to participate in power generation to meet larger ships. Load requirements. The power supply quality and reliable operation of two or more diesel generator sets running in parallel must meet the three basic prerequisites: consistent phase sequence, consistent frequency, and consistent voltage. The phase sequence is determined by the generator manufacturing and cable layout, and the frequency and voltage are the same as The operating parameters and operating characteristics of diesel generators are inseparable. The steady-state speed regulation of the diesel engine and the static voltage regulation of the generator are the decisive factors for the normal parallel operation of the diesel generator set and the running quality. When diesel generators are operated in parallel, if uneven load distribution and unstable load distribution occur, it will directly affect the operating safety of the power plant system, and even