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TYCP PMSM Motor
WPDJ
The advantages of permanent magnet synchronous motors compared with ordinary asynchronous motors
High efficiency, high power factor (The loss of the rotor excitation system is eliminated, and the efficiency is increased by 5-10%)
As shown in Figure 1, take a 37kw permanent magnet motor as an example:
The maximum efficiency of the motor can reach 96%, while the maximum efficiency of the asynchronous motor with the same power can only reach 93%, and the difference in efficiency increases with the decrease of load (power). The rotor does not need electric excitation, the inductance is small, and the power factor is high. Similarly, as shown in Figure 1, the power factor of a 37KW permanent magnet motor can reach up to 0.98, while that of an asynchronous motor is only 0.85, and as the load (power) decreases, the difference in power factor increases greatly.
Wide speed range:
The rotor does not need electric excitation, and the low-speed performance of the motor is good. With the advanced positionless vector control technology, the frequency conversion range of the motor can achieve 25%-150%, while the asynchronous frequency conversion can only achieve 50%-100%, so the permanent magnet motor can realize lower speed no-load operation and realize no-load energy saving. As shown in Figure 2;
Low noise: Reasonable groove and pole fit, magnetic field design, wider operating frequency, lower operating noise;
Compact structure, small size and light weight: the permanent magnet rotor is small in size and high in power (torque) density;
Large starting torque: The starting torque and overload capacity of permanent magnet synchronous motors are one power level higher than those of three-phase asynchronous motors, and the ratio of maximum starting torque to rated torque can be more than 3 times, while that of general asynchronous motors is only 1.6 times.
The energy saving analysis is as follows:
Taking a 37kw air compressor as an example, based on an average air load rate of 70% and an annual operation of 6000 hours,
Loading electricity consumption: 70% loading time x6000 hours/year x37kw=155400 kwh/year
Unloading power consumption: 30% of loading time x 6000 hours/year x 37kw = 19980 kwh/year
Total electricity consumption: 155400 kwh/year + 19980 kwh/year = 175380 kwh/year
Elimination of differential pressure loss: 70% of loading time x 12% of differential pressure loss of two kilograms x 37kw x 6000 hours/year = 18648 kwh/year
Elimination of unloading loss: 30% of loading time × unloading idle current 30% × 37 kw x 6000 hours/year = 19980 kwh/year
Total elimination loss: 18648 kwh/year + 19980 kwh/year = 38628 kwh/year
Electricity saving rate: 38628 kwh/year: 175380 kwh/year × 100%= 22.03%
To sum up, the permanent magnet synchronous motor-driven variable frequency air compressor has outstanding comprehensive advantages compared with ordinary industrial frequency air compressors. The most important advantage is energy saving, and its comprehensive energy saving efficiency reaches more than 40%.
Example of Energy Saving Calculation
Original motor power consumption = 22/0.89- 22 = 2.72kw
Motor power consumption after update = 22/0.959 - 22=0.94kw
Power saving = 2.72 -0.94=1.78kw
Annual power saving = 1.78 * 6000 (here choose 6000 hours/year) = 10680 (kwh)
Calculation method:
Power consumption = rated power / efficiency - rated power
Saving power consumption = original motor power consumption - new motor power consumption
Annual electricity saving = saving power consumption × 6000 hours (can be selected according to actual situation)
The advantages of permanent magnet synchronous motors compared with ordinary asynchronous motors
High efficiency, high power factor (The loss of the rotor excitation system is eliminated, and the efficiency is increased by 5-10%)
As shown in Figure 1, take a 37kw permanent magnet motor as an example:
The maximum efficiency of the motor can reach 96%, while the maximum efficiency of the asynchronous motor with the same power can only reach 93%, and the difference in efficiency increases with the decrease of load (power). The rotor does not need electric excitation, the inductance is small, and the power factor is high. Similarly, as shown in Figure 1, the power factor of a 37KW permanent magnet motor can reach up to 0.98, while that of an asynchronous motor is only 0.85, and as the load (power) decreases, the difference in power factor increases greatly.
Wide speed range:
The rotor does not need electric excitation, and the low-speed performance of the motor is good. With the advanced positionless vector control technology, the frequency conversion range of the motor can achieve 25%-150%, while the asynchronous frequency conversion can only achieve 50%-100%, so the permanent magnet motor can realize lower speed no-load operation and realize no-load energy saving. As shown in Figure 2;
Low noise: Reasonable groove and pole fit, magnetic field design, wider operating frequency, lower operating noise;
Compact structure, small size and light weight: the permanent magnet rotor is small in size and high in power (torque) density;
Large starting torque: The starting torque and overload capacity of permanent magnet synchronous motors are one power level higher than those of three-phase asynchronous motors, and the ratio of maximum starting torque to rated torque can be more than 3 times, while that of general asynchronous motors is only 1.6 times.
The energy saving analysis is as follows:
Taking a 37kw air compressor as an example, based on an average air load rate of 70% and an annual operation of 6000 hours,
Loading electricity consumption: 70% loading time x6000 hours/year x37kw=155400 kwh/year
Unloading power consumption: 30% of loading time x 6000 hours/year x 37kw = 19980 kwh/year
Total electricity consumption: 155400 kwh/year + 19980 kwh/year = 175380 kwh/year
Elimination of differential pressure loss: 70% of loading time x 12% of differential pressure loss of two kilograms x 37kw x 6000 hours/year = 18648 kwh/year
Elimination of unloading loss: 30% of loading time × unloading idle current 30% × 37 kw x 6000 hours/year = 19980 kwh/year
Total elimination loss: 18648 kwh/year + 19980 kwh/year = 38628 kwh/year
Electricity saving rate: 38628 kwh/year: 175380 kwh/year × 100%= 22.03%
To sum up, the permanent magnet synchronous motor-driven variable frequency air compressor has outstanding comprehensive advantages compared with ordinary industrial frequency air compressors. The most important advantage is energy saving, and its comprehensive energy saving efficiency reaches more than 40%.
Example of Energy Saving Calculation
Original motor power consumption = 22/0.89- 22 = 2.72kw
Motor power consumption after update = 22/0.959 - 22=0.94kw
Power saving = 2.72 -0.94=1.78kw
Annual power saving = 1.78 * 6000 (here choose 6000 hours/year) = 10680 (kwh)
Calculation method:
Power consumption = rated power / efficiency - rated power
Saving power consumption = original motor power consumption - new motor power consumption
Annual electricity saving = saving power consumption × 6000 hours (can be selected according to actual situation)
