Single Phase PV Pump Case - INVT BPD VFD

Abstract: About the water pump application, most pumps for household is single phase pump, generally the input power is from AC grid. With the development of the photovoltaic industry, more and more people start to use the new energy, recent years the working efficiency of PV panel becomes more and more high, benefited from the development of the electronic control devices, the performance of the drivers and controllers are more reliable. But until now there is not a suitable solar drive for single phase pump, except INVT iMars BPD. This article will introduce a new product iMars BPD series solar inverter.

Keywords: BPD, Solar panel, Single phase pump

1.Introduction

Generally the single phase pump is little power rate, if use the solar panels, there is some problems need to solve:

1. In most countries, the single phase pump is AC 220V, it needs to use many solar panels when users the solar energy to drive, because the drivers need to keep the output voltage to drive the pumps, and it needs may panels in series to increase the Voc. It will cost too much in that way.

2. In the market, most drivers are special for 3phase pumps, but the internal principle of single phase and 3phase pumps is different, it cannot support to drive the single phase pump directly.

3. Generally the drivers only support 1 power input channel, AC input or PC input, cannot support AC and PV input at the same time.

4. Usually the solar system is in outdoor environment, but the universal drivers IP class is IP20, need to install in the cabinet, also need to add another cooling fans.

Faced with these problems, INVT engineers adopts new software algorithm and designed new hardware to solve these problems, after several months, the new star product iMars BPD series appeared.

2.New solutions to solve the problems

● Reduce the PV panel quantity

Built-in boost hardware to increase the DC bus voltage, keep the pump can work well and water flow is better, reduce the solar panel quantity will reduce the most cost for solar system. Generally the solar panel cost is about 90% accounted for entire system.

● Suitable for single phase pump & 3phase pump.

In order to drive all kinds pumps for all users, the hardware and software are improved, not only for single phase, but also support 3phase. In the future, people can only select one driver to be suitable for all kinds, it can also reduce the product in stock.

● Support AC/PV power input channel

A new platform, built-in the internal contactor and diode, to keep the inverter working always in the day and night, and save the AC power as much as possible.

● IP65 protect level

The general solar pump inverter ingress protection is IP20, need to be installed in the control cabinet. New iMars BPD designed a IP65 case, make sure the BPD can be working well in any outdoor sitation.

3.Principle of iMars BPD

Figure 2: Principle of BPD

4.Commissioning steps for single phase pump

For the single phase pump, there are two ways: (Only PV input)

1. Connect the single phase pump to U and W directly

This way need to set the following parameters:

These parameters is similar with the 3phase pump, need to set the pump motor parameters, and set the control channel.

2.Need to remove the internal capacitor like the following photo.

This way which removed the capacitor needs to set the following parameters:

This way is named two phase control, after remove the internal capacitor, the internal coil is like the 3phase motor. Generally we suggest to adopt this way, because this way can increase the pump lifetime, because for the pump problems, the capacitors often are broken.

5.Conclusion

The BPD performance is so perfect, that BPD is very popular in many Asia countries, just like Thailand/ China/ Vietnam/ Indonesia, and so on.

After adopt BPD, household single phase pump also can use new solar energy, no need to waste too much electricity any more.

And the farmer can plant the crop more and more, and reduce their cost for irrigation.

6.Application in site

Pump: 0.75kW / single phase 220V / 50Hz / 7.5A / 2850rpm

Inverter: iMars BPD1K5TN (AC)

Solar panel: POLY 300WP 4 PCS (4 in series)

AC power: single-phase 220V AC, 50Hz.

Address: Bangkok, Thailand

Reference:

[1] Operation manual of BPD series solar pumping inverter of Shenzhen INVT Electric Co., Ltd.