Grid-Connected Photovoltaic (GCPV) Systems Design

Evaluation Before Design

Step 1 Local Time & Local Solar Time

Step 2.0 Equinox & Solstice

Step 2.1 Sunpath - Polar Coordinates - GAISMA

Step 2.2 Sunpath - Polar Coordinates - PVSYST

Step 2.3 Sunpath - Cartesian Coordinates - PVSYST

Step 3 Determine Collector Tilt Angles

Step 4 Shading Profile

Step 5 PV Array Architecture - Unlimited shed

Designing - PV Modules

Function: Generate DC power (voltage and current)

Step 1 Choose PV Module

Step 2 Design PV array architecture

Step 3 Customer Energy Consumption

Step 4 Budget Constraint

Step 5 AC Power Constraint

Step 6 Maximum Demand Constraint

Step 7 AC Current Constraint

Step 8 Finalise

Designing - Inverter

Function:

Convert DC power to AC power (String level), don't need micro-inverter is if it's installed.
Perform MPPT tracking

Step 1 Choose Inverter

Step 2 Maximum Absolute Input Voltage

Step 3 Maximum MPPT Voltage

Step 4 Maximum System Voltage

Step 5 Maximum Number of PV Modules Based on Inverter

Step 6 Minimum MPPT Voltage

Step 7 Minimum Start Voltage

Step 8 Minimum Number of PV Modules Based on Inverter

Step 9 Inverter Maximum Efficiency

Step 10 Number of Strings per MPPT

Step 11 DC/AC Ratio Per MPPT

Designing - Micro-Inverter

Function: Convert DC power to AC power (PV Panel level), don't need inverter if it's installed.

Step 1 Choose Micro-Inverter (Rated Power)

Step 2 Maximum Open Circuit Voltage

Step 3 Maximum MPPT Voltage

Step 4 Maximum PV Modules In Series

Step 5 Number Of PV Modules Branch

Step 6 Schematic Diagram

Designing - DC Power Optimiser

Function: A small MPPT unit installed at each PV module to reduce mismatch

Step 1 Choose DC Power Optimiser (Power Rating)

Step 2 Maximum Open Circuit Voltage

Step 3 Maximum MPPT Voltage

Step 4 Minimum MPPT Voltage

Step 5 Choose Inverter

Step 6 Schematic Diagram

Designing - BOS Components

BOS: Balance of system components are items in an entire PV system other than PV array.

Step 1 DC Cable Sizing - Current Carrying Capacity

Step 2 DC Cable Sizing - Min. Cross-Sectional Area

Step 3 DC Cable Sizing - Voltage Drop

Step 4 DC Cable Sizing - Voltage Rating

Step 5 DC Cable Sizing - Power Loss

Step 6 DC Cable Sizing - Temperature Effects

Step 7 Fuse

Step 8 Diodes

Step 9 DC Main Switch

Step 10 AC Fuse

Estimating Electrical Outputs Under ROC

Single PV module is assumed for this section.
- For an array of PV modules, after calculating the single PV module electrical outputs, treat them as a normal circuit calculation.
- Exp: Isc_array = Isc_single module* Np (Total PV modules in portrait per string)
ROC: Real operating condition

Step 1 PV Device Temperature

Step 4 Power

Step 2 Current

Step 3 Voltage

Functional Test

Step 1 Open Circuit Voltage Test

Step 2 Short Circuit Current Test

Step 3 Inverter Functional Test

Performance Analysis

Step 1 Collect Weather Data

Step 2 Peak Sun Hour

Step 3 Acceptance Ratio

Step 4 Average Irradiance- Weighted Cell Temperature

Step 5 Output Energy

Step 6 Final System Yield

Step 7 Performance Ratio

Step 8 Measured STC Temperature Performance Ratio

Step 9 Measured Annual-Temperature-Equivalent Performance Ratio

Step 10 Capacity Factor