On hydraulic energy recovery turbine pumps with motorized clutch assemblies

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Well, in a Amine wash tower process, I encountered a hydraulically driven energy recovery turbine (PRT), which drives a lean liquid circulation pump. The pump is equipped with a motor and a one-way clutch. Since this is my first time using this type of equipment, I looked up some information online, but there are still some aspects I don’t quite understand. I would like to ask the experts here for their guidance. Before starting the PRT, first start the motor to drive the pump (assuming a normal speed of 3000 rpm) in order to generate a steady flow of lean amine solution to supply to the amine scrubber. Then start the PRT; when its rotational speed (assuming 3000 rpm under normal operating conditions) reaches a certain value (for example, 2000 rpm?) Thereafter, PRT begins to supply energy to the pump; at this point, the current flowing through the motor starts to decrease, thereby achieving energy savings. My question is: after starting the PRT, how will the current of the motor decrease, and by how much? Assume that before PRT is activated, the current at stable operation of the motor (with a voltage of 6000V) is 50A. When PRT is started and the speed is below 2000 rpm, the energy for the pump is supplied entirely by the motor; in this case, P1=6000*50=300KW. When the PRT speed is exactly 2000 rpm, that is, when the PRT just begins to supply energy to the pump, assuming the energy generated by the PRT is 120 KW, is this 120 KW entirely supplied to the pump? If so, is the energy supplied by the motor side equal to P1 – 120 KW = 180 KW, and would the current then drop suddenly to 30 A? Then, as the speed of the PRT increases and exceeds 3000 rpm, the power required by the pump will be supplied entirely by the PRT. In this case, does the motor essentially come to a stop? I saw a start-up and shutdown manual for PRT, which stated that the PRT should be turned off first before the motor is stopped; therefore, when the pump is driven entirely by the PRT, the motor still cannot be stopped. Thank you all!