THREE PHASE SOLAR PUMP CONTROL WITH MPPT AND VFD

THREE PHASE SOLAR PUMP CONTROL WITH MPPT AND VFD

INTRODUCTION

This system runs all days from morning to evening and delivers constant output throughout the day. It is operated with MPPT, VFD and IGBT, reduces starting current requirement and also delivers constant pure sine wave 3 phase output, It can run the motor or pump set stable even on cloudy and rainy days. This is the only system that runs any kind of new and old pump set so that no need to change existing water pumps. It can also be used for split load operations, domestic, commercial, industrial, agriculture and community water supplies.

“No maintenance for many years”

HP Rating - 1 HP – 10 HP
Input Range (Vmp) - 160 V – 800 VDC
Output - 220 VAC-3 Phase (For 1 & 2 HP), 380 VAC-3 Phase (For 3 – 10 HP)
Working Temperature - 10º C  – 70º C
Cooling Fan - 12 VDC 0.35 amp, start at 70º C and stops at 60º C
Display Information - Equal to or better than that of Electricity power supply
Discharge - Equal to or better than that of Electricity power supply
Head - Up to 1000 ft Vertical and 30000 ft or more Horizontal
Starting Current - Very low starting current is required as the pump rotates slowly and picks up to the maximum RPM.
Working Duration - 7 – 8 Hours in a day depending upon sunlight.
Pump Type - No specific design, any type of new and old pumps can be used ( this is the main advantage of the system )
Power Railing Distance - Less than 1000 ft will give better performance, above that a mild power loss will be there.

SOYO’s 3 phase solar pump control is an electronic device which is a combination of inverter, MPPT and Variable Frequency Drive (VFD) targeted mainly for solar pumping systems for irrigation. The scarcity and poor quality of electricity supply in rural India leads to use of alternate energy for water pumping systems in Indian agriculture. Solar energy which is abundant in Indian states can be harnessed for this purpose. Keeping this in mind, SOYO has launched this 3-phase solar pump control systems which uses solar energy, does not require batteries and pumps water from early mornings till late evenings, even under cloudy conditions.

If a DC motor is used along with the pump there is no MPPT action. If the motor is designed to work at maximum power point during peak sunlight (noon) then at less intensity sunlight (mornings and evenings) the motor will not be at its maximum power point so the full energy is wasted. On the other hand if the motor is designed for maximum power point during less intensity sunlight, it will not be at its maximum power point during noon which again leads to waste of energy. Even though this method is used in many places it is in-efficient.

This system works at its best during any time of the day at any kind of sunlight so effectively we will get 35% extra energy which is being wasted at present using other inefficient methods.

The induction motor has very high starting current which is around eight times of the running current of the motor. If the motor is started with load, the starting current is much higher than this. Without smooth start high wattage panels are required for starting the motors. Because of the smooth start using variable frequency, the motor will start as early as even 6am without taking any starting current. It is practically observed that the starting current will be lesser than the running current from the panel.

The induction motor has maximum efficiency at certain VF ratio. By simply increasing the voltage or the frequency we are reducing the efficiency. If we increase the voltage the slip will reduce so the efficiency and torque will reduce. If we increase the frequency the slip will increase so the efficiency and torque will again reduce. The induction motor has maximum efficiency at a certain slip.

The graph below explains – The system runs at maximum efficiency at all the time by constantly maintaining the motor in the right slip which leads to this maximum efficiency.

Pump Capacity, HP  Panel / Watt   No of Panels Total Watts 
 1  300Wp 900 W 
 2  300 W 1800 W 
 3  335 W 3015 W 
 5  320 W 15  4800 W 
 7.5  340 W 20  6800 w 
 10  340 W 29  9860 w 

As special case where the pumps are used for pumping more head ( above 200 feet ) or for the purpose like drip and lift irrigation @ 15 – 20 % increase in panel wattage would give better performance.