Title: Challenges on Renewable Energy Resources as New Distributed Generations for Equal Power Sharing at Microgrid

Abstract: 

This presentation will talk about on Distributed Generations(DGs) system challenges in order to create an equal power sharing among the DGs in Microgrid configuration. Currently, Microgrid structure has been applied when the generation source is very far from the loads in order to reduce the line losses. As known the input of the DGs can be from solar power generation, wind turbine generation or Battery Storage System (BSS) generation which can create a power between 100kW to 1MW. When there are lot of DGs connected at the same point of common coupling (PCC), the issues on power sharing, maintaining the PCC voltage and high frequency transient deviation during the loads transition are the problems when the DGs are connected to the Microgrid. However, the most severe problem is the power sharing. Therefore, if the DGs are not able to give an equal power sharing between the DG it will cause the DG to be over stress or under stress power. This is because, the DG who has high output power will not deliver the requested power needed by the loads. Meanwhile, the low DG output power is required to supply more power beyond it rated value due to requested high power by the loads. If this happen, the Microgrid system become unbalanced and will create a total shutdown if no action been taken accordingly. Other problem on power sharing is when, the DGs are connected with different line impedance. This line impedance is the transmission line that connected between the DGs to the same PCC.  As known, the DG who use the wind source as the RE input require long transmission line to be transmitted to the load while the solar RE is connected near to the load and require a short transmission line. This difference also will create a non-equal power sharing if the line impedance is not being considered to be compensate. Therefore, both issues require an improved control topology to be applied to the power control structure for the DG. As known, power control structure for DG require hierarchical control layers which includes the current, voltage and power controllers. This presentation will talk about the robust control topologies known as H^∞ (H-infinity) control that can minimize and replace the stability of the existing controller while used more control parameters as the inputs to the H^∞ controller in order replace the hierarchical controller concept. Meanwhile for different lines impedance, the concept of virtual line impedance controller is being in embedded to the power control structure. At the end of this presentation, several rated of power DGs and loads changes cases are being applied in order to see the effectiveness of those improved controllers to the DGs for solving the requirement for equal power sharing.  Lastly, all the results show that, the equal power sharing has been established that not overburden those DGs when connected to the PCC and more stability conditions have been improved.

Biography:

Shamsul Aizam Zulkifli (MIEEE 06) was born in Selangor, Malaysia. He obtained his B.Eng. (Hons) and M.Sc. from Universiti Putra Malaysia, Malaysia, and Ph.D. in Control Systems Engineering from Loughborough University, UK, in 2003, 2006 and 2012, respectively. He is currently an Associate Professor with Department of Electrical Power Engineering, Universiti Tun Hussein Onn Malaysia, Johor, Malaysia. His current research interests include robust control system on power electronics applications, parallel inverter applications and smart grid topology for inverter-grid operation. His homepage is https://sites.google.com/site/acul1508/shamsul-aizam-zulkifli