SEW inverter like many other brands, hop to be more energy-saving as work efficiently. But in actual use, some other situations need to be referred. So today we are going to learn about energy-consumption situation in actual use of SEW inverter:
It is very obvious in energy-saving effect when inverter is applied into overload of water-pump with fan. The centrifugal fan is proportional to the square of pump torque and speed, power is proportional to the cubic speed. Therefore, when the speed is lightly lowered, more energy can be saved to run in mode of variable-speed, for example, without considering the conditions of iron loss, copper loss and heat loss, as motor rotational speed of a centrifugal pump drops to 79% of power speed, the power consumption is just about 50%, this is the result under the relative relationship of every object in centrifugal load defined according to similarity law of fluid mechanical theory.
However, iron loss, copper loss and heat loss need to be considered in actual use, because the variable-frequency operation need to be combined with inverter, fixed-frequency operation is not used, comparatively there will be more energy consumption in inverter, if the energy saved by variable-frequency operation is not enough, it will not achieve energy-saving effect. For example, if motor needs to be work in AC power frequency, when combined with inverter, output power of motor is the same, with the additional energy consumed by inverter, energy-saving effect can not be achieved. |
