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Should long-lead filters be “carrier stripping” devices?

No. It is not the PWM carrier energy that is causing premature insulation breakdowns in motors, it is the high overshoot voltage due to resonance (or wave reflection). Carrier stripping is an old idea with drawbacks such as high losses, large size, and undue stress on the inverter. Carrier stripping filters require huge amounts of capacitance and inductance, both of which cause problems. The inverter will have to supply large amounts of capacitive current each time it switches, and motor terminal voltage will be reduced at the fundamental frequency, resulting in degraded torque per AMP characteristics and dynamic motor response to changes in the load. Also, the impedance decreases the velocity factor of the wire, resulting in poor dynamic response of the motor. The V1k output filter is designed to minimize the impact of the filter on overall system performance (with respect to both torque/AMP and dynamic response concerns). It simply rounds the steep edges of the switched voltage in order to prevent against overshoot, and system losses are held to an almost imperceptible minimum. In addtion, it’s a lot less expensive.