Diesel generator set selection rules, must learn!
2021-10-02
With the rapid development of science and technology and the improvement of public awareness of environmental protection, the increasing demand for functions and the changing application conditions, the traditional diesel generator set and its supporting products (hereinafter referred to as the unit) have been endowed with the connotation of high technology and environmental protection in modern times. The selection rules aims to provide a comprehensive solution for the selection and use of modern units, so as to achieve the purpose of selecting the best performance price ratio, high reliability and environmental protection.
1、 Main characteristics of the unit
Fully functional high integrated control
The traditional separation element control with simple function is developed into modular and highly integrated control widely used in modern high-tech achievements. On the one hand, add control functions, including unit protection, display of operating parameters, historical records and remote computer monitoring, load optimization management, etc; On the other hand, less or even no contact control is realized to improve the reliability of operation.
Environmental protection and low noise operation
Environmental protection and low noise operation can be realized by installing sound proof enclosure or noise reduction device in the machine room; If necessary, install smoke exhaust purifier to realize cleaner exhaust emission.
Fast moving emergency power supply
Vehicle mounted mobile power station and trailer power station can meet the emergency power supply of rapid movement.
2、 Unit category
Standard unit
Standard units are widely used in general places installed in machine rooms. The unit is mainly composed of diesel engine, generator, control system, base, damping device, cooling system, oil supply system, output protection switch, etc.
Protective unit
Protective units shall be used in outdoor places without special requirements for noise. It is mainly composed of standard unit, protective cover, smoke exhaust system, etc. Since the protective cover is not equipped with noise reduction device, as long as it meets the conditions of ventilation, rain and snow protection, it has small appearance and volume and low cost.
Open doors and windows for ventilation during unit operation. Protective power stations can be used in single or multiple parallel. Multiple parallel power stations are especially suitable for occasions with large load change, high reliability requirements for continuous operation and low cost economy, such as supporting oil field drilling rigs.
Sound proof unit
Sound proof units are widely used in outdoor or indoor places requiring protection and noise reduction with special requirements for environmental protection. It is mainly composed of standard unit, sound enclosure, inlet and exhaust noise reduction device and exhaust noise reduction device. The utility model is mainly characterized in that the sound enclosure is provided with sound insulation and absorption layers, the air inlet and exhaust channels are used for noise reduction treatment, and the exhaust adopts the combination of industrial and residential silencers to reduce the noise in the high-frequency and low-frequency bands respectively. The noise of standard sound proof unit is generally 76-85db (a), and that of super sound proof unit is generally 75-60db (a). The super sound proof unit adopts more strict control measures for noise emission on the basis of standard sound proof unit, such as labyrinth air inlet and exhaust channel design.
Super sound proof units generally have large external dimensions, and the manufacturing cost is much higher than that of standard sound proof units. Sound proof units and super sound proof units are usually operated, maintained and overhauled outside the sound proof housing.
Low noise shelter power station and container power station
Low noise shelter power station and container power station are generally used in outdoor places with special requirements for environmental protection. They can be directly placed outdoors without building machine room. At the same time, they have the characteristics of strong mobility and short service cycle. The noise of low-noise shelter power station and container power station is generally 75-85db (a), which can be operated, maintained and overhauled in the shelter and cabin.
Trailer power station
The trailer power station is divided into two types: two wheel trailer and four-wheel Trailer. Two wheel trailer is used for units below 70kw and four-wheel trailer is used for units above 70kw to 500kW. Trailer power station is composed of standard trailer and sound proof unit, which has all the performance and advantages of sound proof unit and is suitable for field operation and mobile power supply.
The trailer is equipped with steering mechanism, traffic warning light and braking device, and is equipped with mechanical outrigger, shock absorber and buffer device. The height of the traction device can be adjusted to meet the requirements of traffic safety. Trailer power station can be pre installed with cable rack and power cable to realize fast power supply. On urban roads and highways above class II, the towing speed of two-wheel tractor can reach 30km / h and that of four-wheel tractor can reach 50km / h.
Vehicle mounted mobile power station
Vehicle mounted power station is widely used in power emergency occasions with high requirements for speed, mobility and reliability, such as communication, television broadcasting, expressway, rescue, power supply and military. Mainly install the unit
In the car compartment, it can be equipped with electric cable winch, multi-channel output socket and mechanical (or hydraulic) outrigger. It can also easily realize the parallel use of multiple on-board mobile power stations. The general noise of vehicle mounted mobile power station is 70-80 dB (a).
3、 Power matching and field application condition power correction
Power concept
Power selection is the core content of unit selection, and its principle is to meet the use requirements on the premise of minimum investment. Firstly, we should clearly understand the definition of various powers, analyze the working condition nature of the unit, and determine the power conditions; Then, according to the site conditions and load characteristics of the unit, calculate, correct and determine the required unit output power.
Iso8528-1:1993 and GB / t2820.1-1997 specify the purpose, quota and performance of AC generator sets. The standard divides the output power of AC generator sets into three types, namely limited time operating power (LTP), basic power (PRP) and continuous power (COP). At the same time, the standard also stipulates the on-site conditions of unit operation: the on-site conditions are determined by the user.
When the site conditions are unknown and not otherwise specified, the following rated site conditions shall be adopted:
Absolute atmospheric pressure: 89.9kPa (or 1000m above sea level)
Ambient temperature: 313k (40 ℃)
Relative humidity: 60%
Site conditions for ISO power:
Absolute atmospheric pressure: 100KPA (or 300m above sea level)
Ambient temperature: 298K (25 ℃)
Relative humidity: 30%
1 continuous power
Between the specified maintenance cycles and under the specified environmental conditions, the maximum power existing in a constant power sequence with unlimited possible operating hours per year is equivalent to the continuous power (COP) in the national standard and ISO standard. It is generally applicable to continuous operation conditions with minimal load change, such as power station or grid connection with municipal power supply.
2 long line power
Between the specified maintenance cycles and under the specified environmental conditions, the maximum power existing in a variable power sequence with unlimited possible operating hours per year is equivalent to the basic power (PRP) in the national standard and ISO standard. It is generally applicable to frequent operating conditions with small load change, such as factories, mines and the army.
3 standby power
The generator set can operate continuously for 300h between the specified maintenance cycles and under the specified environmental conditions, with the maximum power of 500h working hours at most every year. It is equivalent to the limited time operating power (LTP) in the national standard and ISO standard. It is generally applicable to accidental emergency conditions with large load changes such as communication and buildings.
The new version of iso8528-1:2005 has substantially revised the provisions on the types of power rating, which is of guiding significance for users to select imported units and deserves special attention.
1 continuous power (COP)
Under the agreed operating conditions and maintenance according to the manufacturer's regulations, the generator set operates continuously at a constant load and the maximum power of unlimited operating hours per year.
2 basic power (PRP)
Under the agreed operating conditions and maintenance according to the manufacturer's regulations, the generator set operates continuously at variable load and the maximum power with unlimited operating hours per year. The allowable average power output (PPP) over a 24-hour operating cycle shall not exceed 70% of the PPP unless otherwise agreed with the RIC engine manufacturer.
Note: in applications where the allowable average power output PPP is higher than the specified value, the continuous power cop shall be used. When determining the actual average power output (PPP) of a variable power sequence, when the power is less than 30% PrP, it is calculated as 30%, and the shutdown time is not included.
3 limited time operating power (LTP)
Under the agreed operating conditions and maintenance in accordance with the manufacturer's regulations, the generator set can operate for up to 500h per year.
Note: according to 100% time limited operation power, the maximum operation time per year is 500h.
4 emergency standby power (ESP)
Maintenance shall be carried out under the agreed operating conditions and in accordance with the manufacturer's regulations. Once the mains power is interrupted or under the test conditions, the generator set shall operate at variable load and the maximum power of 200H per year. The allowable average power output (PPP) during 24h operation period shall not exceed 70% ESP, unless otherwise agreed with ric engine manufacturer.
*The actual average power output (PPP) shall be less than or equal to the allowable average power output (PPP) as defined by esp.
*When determining the actual average transmission (PPP) of a variable rate sequence, when the power is less than 30% ESP, it is calculated as 30%, and the downtime is not included.
Correction of power field conditions
Under non rated site conditions and special loads, the rated power of the unit needs to be corrected.
Power correction of ambient temperature
When the ambient temperature is too high, the air density decreases, the amount of oxygen decreases and the combustion efficiency decreases, which will reduce the mechanical output power of the diesel engine; At the same time, the generator needs cold air to cool the winding. When the ambient temperature is too high, the cooling effect decreases and the internal temperature of the generator winding increases. In order to ensure that the winding temperature of the generator is within the allowable range, the output power of the generator must also be reduced.
The selection of diesel generator set involves many factors, such as the purpose of the unit, the performance of diesel engine, generator and speed regulating device, field application conditions and so on. It must be comprehensively considered and carefully designed in order to provide users with the best solutions and products to meet their needs.
1、 Main characteristics of the unit
Fully functional high integrated control
The traditional separation element control with simple function is developed into modular and highly integrated control widely used in modern high-tech achievements. On the one hand, add control functions, including unit protection, display of operating parameters, historical records and remote computer monitoring, load optimization management, etc; On the other hand, less or even no contact control is realized to improve the reliability of operation.
Environmental protection and low noise operation
Environmental protection and low noise operation can be realized by installing sound proof enclosure or noise reduction device in the machine room; If necessary, install smoke exhaust purifier to realize cleaner exhaust emission.
Fast moving emergency power supply
Vehicle mounted mobile power station and trailer power station can meet the emergency power supply of rapid movement.
2、 Unit category
Standard unit
Standard units are widely used in general places installed in machine rooms. The unit is mainly composed of diesel engine, generator, control system, base, damping device, cooling system, oil supply system, output protection switch, etc.
Protective unit
Protective units shall be used in outdoor places without special requirements for noise. It is mainly composed of standard unit, protective cover, smoke exhaust system, etc. Since the protective cover is not equipped with noise reduction device, as long as it meets the conditions of ventilation, rain and snow protection, it has small appearance and volume and low cost.
Open doors and windows for ventilation during unit operation. Protective power stations can be used in single or multiple parallel. Multiple parallel power stations are especially suitable for occasions with large load change, high reliability requirements for continuous operation and low cost economy, such as supporting oil field drilling rigs.
Sound proof unit
Sound proof units are widely used in outdoor or indoor places requiring protection and noise reduction with special requirements for environmental protection. It is mainly composed of standard unit, sound enclosure, inlet and exhaust noise reduction device and exhaust noise reduction device. The utility model is mainly characterized in that the sound enclosure is provided with sound insulation and absorption layers, the air inlet and exhaust channels are used for noise reduction treatment, and the exhaust adopts the combination of industrial and residential silencers to reduce the noise in the high-frequency and low-frequency bands respectively. The noise of standard sound proof unit is generally 76-85db (a), and that of super sound proof unit is generally 75-60db (a). The super sound proof unit adopts more strict control measures for noise emission on the basis of standard sound proof unit, such as labyrinth air inlet and exhaust channel design.
Super sound proof units generally have large external dimensions, and the manufacturing cost is much higher than that of standard sound proof units. Sound proof units and super sound proof units are usually operated, maintained and overhauled outside the sound proof housing.
Low noise shelter power station and container power station
Low noise shelter power station and container power station are generally used in outdoor places with special requirements for environmental protection. They can be directly placed outdoors without building machine room. At the same time, they have the characteristics of strong mobility and short service cycle. The noise of low-noise shelter power station and container power station is generally 75-85db (a), which can be operated, maintained and overhauled in the shelter and cabin.
Trailer power station
The trailer power station is divided into two types: two wheel trailer and four-wheel Trailer. Two wheel trailer is used for units below 70kw and four-wheel trailer is used for units above 70kw to 500kW. Trailer power station is composed of standard trailer and sound proof unit, which has all the performance and advantages of sound proof unit and is suitable for field operation and mobile power supply.
The trailer is equipped with steering mechanism, traffic warning light and braking device, and is equipped with mechanical outrigger, shock absorber and buffer device. The height of the traction device can be adjusted to meet the requirements of traffic safety. Trailer power station can be pre installed with cable rack and power cable to realize fast power supply. On urban roads and highways above class II, the towing speed of two-wheel tractor can reach 30km / h and that of four-wheel tractor can reach 50km / h.
Vehicle mounted mobile power station
Vehicle mounted power station is widely used in power emergency occasions with high requirements for speed, mobility and reliability, such as communication, television broadcasting, expressway, rescue, power supply and military. Mainly install the unit
In the car compartment, it can be equipped with electric cable winch, multi-channel output socket and mechanical (or hydraulic) outrigger. It can also easily realize the parallel use of multiple on-board mobile power stations. The general noise of vehicle mounted mobile power station is 70-80 dB (a).
3、 Power matching and field application condition power correction
Power concept
Power selection is the core content of unit selection, and its principle is to meet the use requirements on the premise of minimum investment. Firstly, we should clearly understand the definition of various powers, analyze the working condition nature of the unit, and determine the power conditions; Then, according to the site conditions and load characteristics of the unit, calculate, correct and determine the required unit output power.
Iso8528-1:1993 and GB / t2820.1-1997 specify the purpose, quota and performance of AC generator sets. The standard divides the output power of AC generator sets into three types, namely limited time operating power (LTP), basic power (PRP) and continuous power (COP). At the same time, the standard also stipulates the on-site conditions of unit operation: the on-site conditions are determined by the user.
When the site conditions are unknown and not otherwise specified, the following rated site conditions shall be adopted:
Absolute atmospheric pressure: 89.9kPa (or 1000m above sea level)
Ambient temperature: 313k (40 ℃)
Relative humidity: 60%
Site conditions for ISO power:
Absolute atmospheric pressure: 100KPA (or 300m above sea level)
Ambient temperature: 298K (25 ℃)
Relative humidity: 30%
1 continuous power
Between the specified maintenance cycles and under the specified environmental conditions, the maximum power existing in a constant power sequence with unlimited possible operating hours per year is equivalent to the continuous power (COP) in the national standard and ISO standard. It is generally applicable to continuous operation conditions with minimal load change, such as power station or grid connection with municipal power supply.
2 long line power
Between the specified maintenance cycles and under the specified environmental conditions, the maximum power existing in a variable power sequence with unlimited possible operating hours per year is equivalent to the basic power (PRP) in the national standard and ISO standard. It is generally applicable to frequent operating conditions with small load change, such as factories, mines and the army.
3 standby power
The generator set can operate continuously for 300h between the specified maintenance cycles and under the specified environmental conditions, with the maximum power of 500h working hours at most every year. It is equivalent to the limited time operating power (LTP) in the national standard and ISO standard. It is generally applicable to accidental emergency conditions with large load changes such as communication and buildings.
The new version of iso8528-1:2005 has substantially revised the provisions on the types of power rating, which is of guiding significance for users to select imported units and deserves special attention.
1 continuous power (COP)
Under the agreed operating conditions and maintenance according to the manufacturer's regulations, the generator set operates continuously at a constant load and the maximum power of unlimited operating hours per year.
2 basic power (PRP)
Under the agreed operating conditions and maintenance according to the manufacturer's regulations, the generator set operates continuously at variable load and the maximum power with unlimited operating hours per year. The allowable average power output (PPP) over a 24-hour operating cycle shall not exceed 70% of the PPP unless otherwise agreed with the RIC engine manufacturer.
Note: in applications where the allowable average power output PPP is higher than the specified value, the continuous power cop shall be used. When determining the actual average power output (PPP) of a variable power sequence, when the power is less than 30% PrP, it is calculated as 30%, and the shutdown time is not included.
3 limited time operating power (LTP)
Under the agreed operating conditions and maintenance in accordance with the manufacturer's regulations, the generator set can operate for up to 500h per year.
Note: according to 100% time limited operation power, the maximum operation time per year is 500h.
4 emergency standby power (ESP)
Maintenance shall be carried out under the agreed operating conditions and in accordance with the manufacturer's regulations. Once the mains power is interrupted or under the test conditions, the generator set shall operate at variable load and the maximum power of 200H per year. The allowable average power output (PPP) during 24h operation period shall not exceed 70% ESP, unless otherwise agreed with ric engine manufacturer.
*The actual average power output (PPP) shall be less than or equal to the allowable average power output (PPP) as defined by esp.
*When determining the actual average transmission (PPP) of a variable rate sequence, when the power is less than 30% ESP, it is calculated as 30%, and the downtime is not included.
Correction of power field conditions
Under non rated site conditions and special loads, the rated power of the unit needs to be corrected.
Power correction of ambient temperature
When the ambient temperature is too high, the air density decreases, the amount of oxygen decreases and the combustion efficiency decreases, which will reduce the mechanical output power of the diesel engine; At the same time, the generator needs cold air to cool the winding. When the ambient temperature is too high, the cooling effect decreases and the internal temperature of the generator winding increases. In order to ensure that the winding temperature of the generator is within the allowable range, the output power of the generator must also be reduced.
The selection of diesel generator set involves many factors, such as the purpose of the unit, the performance of diesel engine, generator and speed regulating device, field application conditions and so on. It must be comprehensively considered and carefully designed in order to provide users with the best solutions and products to meet their needs.