Modelling and allocation of open‐UPQC‐integrated PV generation system to improve the energy efficiency and power quality of radial distribution networks

Abstract

The study presents the modelling and allocation strategy for open unified power quality conditioner (UPQC-O) integrated photovoltaic (PV) generation system in radial distribution networks to improve the energy efficiency and PQ. An UPQC is a custom power device, which consists of series and shunt inverters. In UPQC-O, these inverters are placed in different locations in a network. There is a communication channel to share the information among these inverters to select the respective set point. Two models proposed are: (i) UPQC-O with battery and PV array (UPQC-O-WB) and (ii) UPQC-O with only PV array (UPQC-O-WOB). In UPQC-O-WB, the energy generated by PV array is stored during its operation hour to utilise it during peak hour. However, in UPQC-O-WOB, the energy generated by PV array is directly injected to the network. The proposed models are incorporated in the forward-backward sweep load flow to determine the operational parameters such as bus voltage. An optimisation problem is formulated to determine the optimal placement of UPQC-O with PV array in distribution networks. The objective function includes the investment and operational costs of inverters, battery and PV array, and the cost of energy loss. The particle swarm optimisation is used as the solution strategy.

Simultaneous optimisation of photovoltaic hosting capacity and energy loss of radial distribution networks with open unified power quality conditioner allocation

“…The percentage of total load protected from a given value of upstream voltage sag is called PVSML. PVSML at bus j is calculated as [14] PVSML j = Re V¯j I¯* o j TPAPD base + PL 1 × 100 (6) where V¯j is the voltage at bus j, I¯* o j is the line current flowing from bus o to j. TPAPD base is the total peak active power demand of base-case network and it is determined by aggregating the peak active power load demand of all the buses of a network. PL 1 is the base-case network power loss during peak demand hour.…”

“…Thus, they are capable of only injecting active power into the network during the operational hour. • The PV generation hours and the peak demand hours do not coincide with each other [14]. The peak demand takes place during evening 6 to 10 PM and this duration is named as peak hour.…”

“…In this work, a multi-objective planning problem is formulated for the simultaneous optimisation of PVHC and energy loss of distribution networks. The open unified power quality conditioner (UPQC-O) is used as an ANM technology to simultaneously provide the reactive power compensation and PQ mitigation [14]. It consists of two voltage source inverters, i.e.…”

Model Predictive Controller based Unified Power Quality Conditioner for Voltage Regulation Studies in 33- Bus Closed Loop Distribution System

“…Modeling, insertion of 'Open-UPQC' integrated PVG-system for improving efficiency of energy & PQof Radial-Distribution-Networks.Similar way UPQC-OWOB, energy extracted from PVA will directly given to the model. Recommended models incorporates in forward&backward-sweeps of load flows to evaluate operating-parameters like node-voltage [14][15][16][17][18].…”

Control Strategy of Intergrated Photovoltaic-UPQC System for DC-Bus Voltage Stability and Voltage Sags Compensation

“…For instance, the stable control issue of dc-bus voltage, which is closely related to the PV array output power from the point of photovoltaic generation and the compensation effect from the perspective of power quality regulation. Most existing literature pay more attention to the model and control of series and shunt compensators [32][33][34], with a lack of discussion on the schemes for dc-bus voltage stability under solar irradiance fluctuation and grid disturbances. Recently, some researchers have been gradually paying attention to the dc-bus voltage regulation.…”