TITLE:
Optimum Sizing and Siting of an Embedded Solar Photovoltaic Generation: A Case Study of 33 kv Sub-Transmission Network at Tarkwa, Ghana
AUTHORS:
Armstrong Okai Ababio, Gabriel Takyi, Emmanuel Kwaku Anto
KEYWORDS:
Grid Integration, Embedded Solar PV, Sub-Transmission Network, Technical Losses
JOURNAL NAME:
Journal of Power and Energy Engineering,
Vol.9 No.3,
March
30,
2021
ABSTRACT: The interconnection of Solar PV to the Tarkwa Bulk
Supply Point (BSP) has become necessary in order to provide additional capacity
to meet the ever-increasing demand of Tarkwa and its environs during the day.
The Solar PV Plant will support the Tarkwa BSP during the day. In this study, a
grid impact analysis for the integration of Solar PV plant at three points of
common coupling (PCC) at Tarkwa Bulk Supply Point’s (BSP) 33 kV network of the
Electricity Company of Ghana was carried out. The three PCCs were Tarkwa BSP,
Ghana Australia Gold (GAG) Substation and Darmang Substation. Simulations and
detailed analysis were carried out with the use of CYME Software (Cyme 8.0 Rev
05). The Solar PV was integrated at varying penetration levels of 9 MWp, 11
MWp, 14 MWp, 16 MWp, 18 MWp, 20 MWp and 23 MWp (representing penetration levels
of 40%, 50%, 60%, 70%, 80%, 90% and 100%, respectively) of the 2020 projected
light demand of Tarkwa BSP 25.15 MVA network at an average power factor of
0.903. From the study, the optimum capacity of Solar PV power that could be
connected is 9 MWp at an optimum inverter power factor of 0.94 lagging, and the
GAG Substation was identified as the optimal location. The stiffness ratio at
the optimal location was determined as 41.9, a figure which is far greater than
the minimum standard value of 5, and gives an indication of very little voltage
control problems in the operation of the proposed Solar PV interconnection. The
integration of the optimum 9 MW Solar PV Plant to the Tarkwa network represents
an additional 12.77% capacity, decreased the technical losses by 7.76%, and
increased the voltage profile by 1.97%.