With the improvement of the quality of life and the power failure caused by power peak sometimes, the standby power supply is needed, and the diesel generator set as the standby power supply is more and more widely used. How should we choose the diesel generator set? Now let's share it with Guangxi Dingbo Power.
I. Type selection of diesel generator set.
1. The diesel generator set shall adopt the emergency type of fast self starting, and the time for the first automatic restoration of power supply after power loss can be 15s~20s. The unit shall be ready for automatic startup at any time and can be successfully put into operation for up to 3 consecutive automatic starts.
2. The diesel engine should be high-speed (considering economy) and exhaust gas turbocharged.
3. The diesel engine should be started by electricity.
4. The diesel engine shall be cooled by closed circulating water.
5. The generator should adopt a fast response excitation system (to meet the requirements of fast loading).
6. The connection of generator shall be star connection, and the neutral point shall be able to lead out.
II. Capacity selection of diesel generator set.
1. The load calculation method of diesel generator set adopts conversion coefficient method. That is, in case of emergency shutdown of each unit, the sum (kW) of the rated power of the unit loads (including rotating and stationary loads) that may operate at the same time is multiplied by the conversion factor to obtain the calculated load (kVA), and then the active power (kW) of the calculated load is obtained by multiplying the calculated load (kVA) and the calculated load power factor (0.86). The load calculation principle is the same as that of the station transformer, but the unit load operation rule should be considered. The security loads that can be operated stagger in time shall not be calculated completely. The unit loads that can be operated simultaneously can be counted in stages, and the larger one shall be taken as the calculated power.
2. The selection of generator capacity shall meet the following requirements:
① The continuous output capacity of the generator shall be greater than the maximum calculated load. When each unit is equipped with one diesel generator set, the maximum calculated load is the security load of the unit. When two unit units are equipped with one diesel generator set, the maximum calculated load is the sum of the unit loads of the two unit units, which is determined by technical and economic comparison.
② When the generator starts a motor with maximum capacity with load, the short-time overload capacity shall be verified. In general, if the generator can withstand 150% Se under hot condition for 15s, 1.5 can be taken. When the manufacturer has clear data (usually up to 1.8~2 times), it can be selected according to the actual situation. When the preliminary verification cannot be satisfied, the operating load and starting load of the generator shall be re calibrated according to the method of phasor sum, or "soft start" shall be adopted to reduce Kq value. If it cannot be met, the allowable overload capacity of the generator within the actual starting time of the motor shall be obtained from the manufacturer.
3. Recheck the output power of diesel engine.
① When the environmental conditions of the actual use place are different from the standard use conditions, the output power of the diesel engine shall be corrected according to the correction factor given by the manufacturer.
② The output power under continuous 1h operation condition shall be verified according to the following requirements: the design considers that the diesel generator unit shall have the ability to bear the maximum security load within 1h of power failure in the whole plant. The allowable load capacity of the diesel engine for 1h is 1.1 times of the rated power.
③ The first loading capacity of the diesel engine shall be verified according to the following requirements: the first loading capacity of the diesel generator set guaranteed by the manufacturer shall be 50% of the rated power. Therefore, the actual output power of the diesel engine is required to be no less than twice the starting active power initially put into operation.
Founded in 2006, Guangxi Dingbo Power Equipment Manufacturing Co., Ltd. a wholly-owned subsidiary of Guangxi Dingbo Power Group, is one of the earliest manufacturers of generating sets in China. Over the past 20 years, the company has won the recognition of users by relying on advanced testing equipment, modern production technology, professional manufacturing technology, perfect quality management system, strong R&D technology strength. For more details, please contact us with firstname.lastname@example.org.