Selecting the right diesel generator set is crucial for ensuring reliable power supply, optimizing costs, and meeting operational requirements. This guide outlines key factors to consider when choosing a diesel generator set, including power requirements, environmental conditions, noise reduction options, and specific application needs.
Soundproof Generator Sets
Soundproof generator sets are widely used in outdoor or indoor environments where noise reduction is essential for environmental protection. These sets mainly consist of a standard generator, a soundproof enclosure, an intake and exhaust noise reduction system, and an exhaust silencing system.
Key Features
- The soundproof enclosure is equipped with insulation and sound-absorbing layers.
- The intake and exhaust channels are designed for noise reduction.
- The exhaust system combines industrial and residential silencers to reduce both high-frequency and low-frequency noise.
Standard soundproof generator sets typically produce noise levels between 76-85 dB(A), while super soundproof generator sets have stricter noise control measures and achieve levels between 75-60 dB(A). The super soundproof models use advanced noise reduction techniques, such as labyrinth-style airflow channels, to minimize emissions further.
These generators are larger in size and have higher production costs than standard models. Maintenance and operation are typically conducted outside the soundproof enclosure.
Containerized Power Stations
Low-noise containerized power stations and mobile container power stations are ideal for outdoor environments requiring noise reduction. These power stations:
- Can be used outdoors without the need for additional structures.
- Offer high mobility and short deployment times.
- Have noise levels ranging from 75-85 dB(A).
- Allow for operation, maintenance, and servicing inside the container.
Trailer-Mounted Power Stations
Trailer-mounted power stations come in two types:
- Two-wheel trailers – for generator sets up to 70 kW.
- Four-wheel trailers – for generator sets from 70 kW to 500 kW.
These power stations consist of a standard trailer and a soundproof generator set, combining mobility with noise reduction. They are suitable for field operations and emergency power supply.
Key Features
- Equipped with a steering mechanism, brake system, and warning lights.
- Adjustable tow hitch height to comply with road safety standards.
- Pre-installed cable racks for quick power deployment.
- Maximum towing speeds:
- Two-wheel trailers – up to 30 km/h on urban and secondary highways.
- Four-wheel trailers – up to 50 km/h.
Understanding Generator Power Ratings
Choosing the right generator power rating is crucial for balancing cost efficiency and operational needs. Power selection involves understanding different power definitions and adjusting for environmental factors.
Generator Power Classifications (According to ISO 8528-1:1993 and GB/T2820.1-1997)
- Limited Time Running Power (LTP) – Maximum power for short-term operation.
- Prime Power (PRP) – Continuous operation with varying loads.
- Continuous Power (COP) – Uninterrupted operation at a constant load.
When environmental conditions are not specified, the following standard conditions apply:
- Absolute air pressure: 89.9 kPa (or altitude 1000m)
- Ambient temperature: 40°C
- Relative humidity: 60%
For ISO-rated power, the reference conditions are:
- Absolute air pressure: 100 kPa (or altitude 300m)
- Ambient temperature: 25°C
- Relative humidity: 30%
Power Corrections for Environmental Factors
Temperature Correction
Higher temperatures reduce air density, leading to lower oxygen intake and combustion efficiency in diesel engines. Similarly, generators require cool air for winding cooling, and high temperatures reduce cooling efficiency, causing power derating.
Power loss varies by engine model:
- John Deere:
- Most models lose 1.5% power per 5.5°C increase.
- 6125HF070 loses 0.5% per 5.5°C increase.
- Volvo Penta:
- Models like TD520GE, TAD520GE, TAD720GE lose 2-3% per 5°C increase.
- TAD941GE, TAD1241GE, TAD1640GE have no power loss up to 4400m altitude.
- Mitsubishi: 2% power loss per 5°C increase.
- Stamford Generators: 3% power loss per 5°C increase.
If specific manufacturer data is unavailable, a general rule of thumb is:
- For temperatures above 40°C, power decreases by 3-4% per 5°C increase.
Altitude Correction
At higher altitudes, air density decreases, reducing both engine and generator performance. Power loss varies by brand and model:
- John Deere:
- Some models lose 3% power per 300m increase.
- Others require correction only above 2500m.
- Volvo Penta:
- Power loss 4% per 500m increase.
- Certain models remain unaffected below 4400m.
- Mitsubishi: 1.5% power loss per 300m increase.
- Stamford Generators:
- Below 4000m: 3% power loss per 500m.
- Above 4000m: 4% power loss per 500m.
For generators at altitudes exceeding 1000m, a general guideline is to reduce power by 4-5% per 500m increase unless manufacturer data specifies otherwise.
Advantages of Electronic Fuel Injection (EFI) Diesel Engines
EFI technology precisely controls fuel injection timing and quantity based on environmental conditions. This reduces power loss in high-altitude and high-temperature environments, making EFI engines more efficient and economical in such conditions.
Power Correction for Non-Linear Loads
Non-linear loads contain capacitive or inductive components, such as:
- Data center equipment (UPS systems)
- Airport runway lighting
- Telecom and financial systems
These loads generate harmonic currents, particularly 5th and 7th harmonics, which can:
- Cause generator instability, AVR damage, or load malfunctions.
- Trigger excessive voltage fluctuations, damaging sensitive equipment.
Solutions for Non-Linear Load Compatibility
- Use Permanent Magnet Excited (PMG) Generators
- PMG provides independent excitation, ensuring stable voltage under fluctuating loads.
- Increase Generator Capacity Without Changing Engine Power
- Matching a larger generator with a smaller engine improves transient response.
- This method reduces costs and prevents underloading issues.
When selecting generators for UPS loads, consider using a generator rated at 2-3.5 times the UPS capacity. However, using PMG excitation and optimized matching can significantly reduce the need for oversized generators, ensuring cost-effective and reliable operation.
Conclusion
Proper diesel generator selection requires evaluating:
- Power requirements – PRP, LTP, and COP classifications.
- Environmental conditions – Temperature and altitude corrections.
- Load types – Linear vs. non-linear loads.
- Noise reduction needs – Standard vs. super soundproof models.
- Mobility requirements – Containerized and trailer-mounted solutions.
By understanding these factors, businesses can ensure optimal performance, efficiency, and long-term reliability of their diesel generator sets.
Whether you’re looking for industrial or marine generator sets, we’ve got you covered. With over 20 years of experience, we deliver high-quality, durable, and efficient generator solutions to meet your needs.
Contact us today to discuss your requirements and get the best pricing for your power solutions! Don’t settle for less when it comes to reliable power – choose Fuzhou Hosem Power for all your generator needs.