## 4 Experimental Results
### Load an EV Battery Profile  
In this case, a user defined EV battery charge profile has been defined. It consists of a charging process of 5 min, starting the voltage at 350 V with a demanded power of 12 kW. This demanded power decreases until reaching 6.5 kW and the voltage increases up to 358 V, the moment when the emulator sends a stop command to the charger through CHAdeMO communication. The evolution of the voltage and current measured at the emulator output is shown in Figure 16. At the beginning of the charging process, the CHAdeMO's isolation test procedure is performed by the charger, setting 500 V at the input of the emulator. Once the charger verifies that there is not any isolation problem, it closes the emulator power relay. From this point, the emulator control the output voltage and it sends the demanded power to the EVSE, which is defined in the loaded profile of the emulator. This profile can be modified in order to perform different user tests, changing current, voltage and time of the vehicle charge and executed as many times as needed. This feature allows the repeatability of the test, which makes it possible to compare and analyze the response of different HUTs.  
Figure 14: Experimental results of the variation of the current set-point from 65 A to \(-\)65 A at 300 V set-point. Voltage (**top**) and current (**bottom**) transient evolution is depicted in the figure.  
To test the reactive power compensation, the previous EV battery charging profile has been used, but also adding a profile of reactive power consumption to the charger. A  
Figure 16: Emulation of an EV charging for 5 min. The upper graph is the output voltage of the charger and the lower graph is the charged current.  
Figure 15: Experimental results of the variation of the voltage set-point from 300 V to 200 V at 10 kW set-point. Voltage (**top**) and current (**bottom**) transient evolution is depicted in the figure.  
profile with abrupt changes in the reactive consumption has been configured in order to verify the behaviour of the emulator. In this case, the grid analyzer has been placed at the output of the HUT, with an open-loop control implemented in the EBox. Figure 17 shows the results of the test, measured with a power analyzer data logger (Fluke 435-II) at the PCC of the facility. Firstly, the reactive power consumption, without compensating it by the emulator, has been measured by a grid analyzer. Secondly, the same test has been repeated and measured, but this time compensating the reactive power consumption by the emulator. The data from the two measurements have been downloaded and synchronized.  
The steady reactive power consumption of the HUT is completely compensated by the emulator. However, if the HUT has quick step changes in the reactive power consumption in less than the execution time control of the EBox, it cannot be compensated properly. This behaviour can cause problems in the facility's PCC if the electric protection devices are less than the peak current occurred during the transition. To resolve this issue, it is possible to perform a power consumption characterization of the HUT at every charge/discharge current, and configure a charge/discharge profile in the emulator, including the reactive power that has to be generated by the emulator in order to compensate it.