What is the Problem?
Batteries are used (and will be used) in renewable generation plants to compensate quick variations in the output of these resources, among other things. It could be very useful for researchers and engineers to know the kind of regime that battery will experience in such applications in real-world condition beyond simulation studies.
Why is it Interesting?
Having insights in to the different ways that battery is stressed during ramp-rate control mode can help to select suitable battery for the application, design better battery kWh and kW sizes more realistically, and develop energy management systems for battery operation which account for the real-wrold conditions.
What is the Approach?
In this paper, one year of operational data of a 600 kW/760 kWh Li-Polymer battery during ramp-rate control mode of a 3.275 MWp PV plant at the UQ Gatton campus are analysed. Maximum, minimum, average, standard deviation, skewness, and kurtosis are calculated for different parameters while statistical models are derived based on the given data.
What is New?
The insights offered to a utility-scale battery experience operating in a PV plant are unique in this paper. Battery energy, power, SOC, cell temperature, and time difference between two consecutive events are among the parameters that have been evaluated. In addition, technical and operational values of a super-capacitor in such a system is hypothesized. Moreover, the impact of PV inverter operation on the ramping events on the DC and AC sides are analysed which resulted in very important observations.
How was it Tested?
This paper is developed based on actual data of a battery system in ramp-rate control mode. So, there is no test required in this kind of study.