I didn't increase the RPM- the originally supplied Delta motor was 3450 RPM. I used the same pulleys, so there was no change in the approx 5000+ cutter head RPM which is the proper speed for almost every jointer with straight or helical-segmented cutter heads. You can verify online, check the specs- some examples (cutter head RPM): Grizzly 8"(4800), Jet 8" (5500), Powermatic 8" (6000-7000). So unless you have a pretty large diameter pulley* on the motor and a pretty small one on the cutter head you really should have a 3450 RPM motor.
Multiply pulley ratio times motor RPM to determine cutterhead RPM
* I used the ratio of cutterhead RPM and motor RPM to determine pulley sizes you might need= 5400 / 1725 = 3.13 which means if you use a 1725 RPM motor, you'll need a 6.26" diam. pulley on the motor and a 2" diam. pulley on the cutter head to achieve 5400 RPM at the cutterhead. (note- changing the pulleys alone will result in less power to the cutterhead.)
It is a common misunderstanding/misreading of inverter specs- inverters do not decrease the motor hp- most inverters are designed to run on higher voltages (240V (and higher) / 3 phase power source), but many can also produce 3ph / 240V from single phase / 240V input, and some from a 120V input. It all depends on the inverter and specs- they are built differently and have different specs. You may need to derate the inverter to protect the inverter circuitry, not the motor, e.g. if an inverter, while supplied with single phase / 240 V, is primarily designed to operate a 2 hp motor, it may also operate on 120V but may only be rated for a 1.5 hp motor when supplied with 120V. It should say in the inverter specs. (often a table)