Solar Drive PV Array Design

EMHEATER offers 2 different Solar Drive (Solar VSD) models as follows:

EM15 SP1: Solar DC ~360V (or Single-Phase AC 220V ±15%) Input
- 3 Output Options:
  - Single-Phase (~220V) AC Output (motor with capacitor)
  - Single-Phase (~220V) AC Output (motor without capacitor)
  - 3-Phase (~220V) AC Output
EM15 SP3: Solar DC ~650V (or 3-Phase AC 380V ±15%) Input and 3-Phase (~380V) AC Output

For Solar Array sizing there are 2 critical aspects to consider during the design process:

Minimum PV Array Voltage

This is dependent on Solar Drive Series used and has minimum start-up voltage requirements, maximum voltages allowed and suggested voltage ranges for optimal performance. Voltages for each series as follows:

SP1
- Minimum Start-up Voltage: 120Voc
- Maximum Allowed Voltage: 400Voc (above 400Voc will cause damage to drive components)
- Ideal Voltage: 360+ Voc
SP3
- Minimum Start-up Voltage: 280Voc
- Maximum Allowed Voltage: 750Voc (above 800Voc will cause damage to drive components)
- Ideal Voltage Range: 650+ Voc

Minimum PV Array Power (kW)

The total PV Array kW requirement is dependent on the Solar Drive kW rating – should be at least 1.3 x the Solar Drive kW rating. This should however ideally be more than that depending on the required working hours per day or other aspects such as minimum pressure required for pumping solutions etc. This is to ensure the system can provide enough working hours in the day which will fluctuate based on the PV Array output during different seasons of the year and at different hours and conditions of each day. Most installers prefer a ratio of a PV Array kW size of 2 x that of the Solar Drive kW rating.