Step Down Solar PV High DC Voltage

I have a PV panel which is rated at 5HP. The DC voltage generated by the panel is connected to the DC bus of its respective AC drive which then drives a motor to pump water. I need to step down this DC voltage only to generate a signal linear to this and to be fed to the AC drive as a reference voltage, i.e., when DC voltage is full, this stepped down voltage of 10V will be given to the drive, and with a fall in DC voltage, a proportional stepped down voltage will be given to the drive to reduce the output voltage from the drive in a linear V/F ratio.

I was thinking of using multiple DC-DC buck converters, one after the other in order to step down the voltage to the desired level.

Are they any other solutions?