## 3 Results  
### Estimated Absorbed Power for the Considered Architectures  
For standard, regenerative, high-low, and VPD plant architectures, the inertial effects can usually be neglected; however, this is not true for the architecture with DCP. For the first four architectures, the angular acceleration or deceleration ramps experienced by the asynchronous motor during operation are caused by the phenomenon of motion irregularity. As a result of the cyclic and periodic loading (the motion of the pumping unit), the speed of the electric motor fluctuates in a typically very small range, which is around the rated speed. The resulting moments of inertia generally do not significantly change the electrical active power consumption data. Table 12 summarizes the absorbed active and reactive power in each phase and their values in the cycle for each architecture considered. They have been estimated on the basis of the previously performed dimensioning and the mechanical and electrical analysis of the system. In Figure 17, the average values of the active power absorbed in the working cycle for each considered architecture are drawn with histograms for a more effective visual comparison. For the regenerative configuration, the white part of the bar shows the energy savings compared to the standard solution. For the other configurations, the portion of energy saved is also visually represented, but the regenerative configuration is used as a reference. The analysis was performed for both the static and dynamic cases for the DCP architecture, and the estimated data of active electrical power consumption with respect to the architectures with DCP show that the estimated average active power consumption is 1.63 kW higher when dynamics are taken into account. This obviously non-negligible difference is caused by the presence of very strong dynamic effects during the operation of the architecture with DCP. In this system architecture, the fluctuations of the motor speed are very large (even on the order of 1000 RPM) and typically occur in times on the order of fractions of a second in the considered application. In contrast, for the architectures that do \begin{table}
\begin{tabular}{c l l} \hline
**Circuit Element** & **Parameter** & **Value** \\ \hline \multirow{4}{*}{Electric Motor} & Code & Parker Mod. MS54133 KFA \\  & Type & 4 poles—square case \\  & Nominal power & 16 (kW) \\  & Nominal speed & 1500 (RPM) \\  & Nominal torque & 102 (Nm) \\  & Efficiency & 0.85 \\ \hline \multirow{4}{*}{Frequency Converter} & Code & Parker Mod. 31V—4G0060 \\  & Nominal electric power & 30 (kW) \\  & Nominal current & 60 (A) \\  & Maximum current & 66 (A) \\  & Efficiency & 0.98 \\ \hline \multirow{4}{*}{Pump} & Code & Parker Mod. Mod. T7B E15 \\  & Type & Fixed-displacement vane pump for variable speed drives \\  & Max displacement & 50 (mL/min) \\  & Speed range & 300–2700 (RPM) \\  & Nominal pressure & 240 (bar) \\ \hline \multirow{4}{*}{Directional Valve} & Code & Parker Mod. D41 FEZ32 FC1 NB70 \\  & Type & Pilot-operated proportional DCV with regeneration—A hybrid \\  & Nominal flow rate & 200 (L/min) \\  & Nominal pressure drop & 5 (bar) \\ \hline \multirow{4}{*}{Pressure Relief Valve} & Code & Parker Mod. R4V0353P0 PM10 VA1 \\  & Type & Pilot-operated proportional pressure relief valve \\ \cline{1-1}  & Nominal flow rate & 250 (L/min) \\ \cline{1-1}  & Maximum pressure & 350 (bar) \\ \hline \end{tabular}
\end{table} 
Table 11: Designations and technical data of the main elements of the DCP architecture, in the dynamic case. not use DCP, the motor speed fluctuations are on the order of 10 RPM. In the case of the DCP architecture, therefore, dynamic sizing that takes inertial effects into account provides a more reliable estimate of the energy savings than static sizing. Figure 18 reports a comparison between the considered architectures, similarly structured to the one in Figure 17, referring in this case to the hourly cost of the electricity absorbed.