SHENZHEN INVT ELECTRIC CO., LTD. CHV160 Operation Manual
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In the case that the distance between inverter and motor is more than 100 meters, as long
cable can have parasitic capacitance to ground and cause large current leakage, so the
inverter will have frequent over-current protection, it is necessary to add output reactor to
compensate this fact, and in the meantime to avoid damage to motor insulation.
4.5.3.2 Noise Filter at Output Side
Noise filter installed at the output side can minimize current leakage at the connecting wire
and the wireless noise caused by cable between inverter and motor. Its Connection is shown
in following diagram.
Figure 4-7 Wiring Diagram at Motor Side of Main Circuit
4.5.4 Feedback Unit Wiring
Feedback unit can feed back the electricity generated by regenerative braking of motor to
the grid. CHV feedback unit uses IGBT as the rectification feedback, which, if compared with
traditional 3 phase inverse parallel bridge-type rectification unit, has an allocation of feedback
harmonic wave distortion
less than 4% of first harmonic, and thus causes less pollution to the
grid. Feedback unit is extensively used at oil field for pumping unit, centrifugal machine and
hoister and so on.
4.5.5 Wiring of common DC bus
For multiple motors application for paper manufacturing machinery and chemical fiber
industry, common DC bus is normally used. At any time, some motors are in operating
condition while some others are at regenerative braking (generating electricity) condition. In
this case the regenerated electricity is automatically balanced at the DC bus
and can be
supplied to motors at operating condition, reducing the electricity consumption of the whole
system from the grid, more energy saving than traditional single inverter for single motor. Its
wiring diagram is shown as following figure:
