Composition, operation and classification of solar photovoltaic pumps
Solar photovoltaic pumps are also called photovoltaic pumps. That is to say, the photovoltaic pumping system is driven by the power generated by the photovoltaic array. The whole system is mainly composed of photovoltaic array, solar pumping inverters, and pumps. It is an optoelectronic-mechanical integration system that has developed rapidly in recent years. It is the most attractive water supply mode in sunny areas in the world, especially in remote areas where there is no electricity or electricity.
I. System Composition:
1. Photovoltaic arrays: also known as solar cell modules, mainly convert solar energy into electrical energy to provide working power for load pump motors.
2. Solar pumping inverters or controllers: the operation of solar pumps is controlled and regulated. The pumps are driven by the electric energy emitted by solar arrays, and the output frequency is adjusted instantly according to the change of sunshine intensity so that the output power is close to the maximum power of solar arrays.
3. Water pumps: Generally speaking, the machines that lift, transport or increase the pressure of liquids, that is to say, change the mechanical energy of the prime mover into liquid energy, so as to achieve the purpose of pumping liquids, are collectively called pumps.
II. Operational process:
Utilizing the power generated by solar cells, high-efficiency water pumps are driven by DC, permanent magnet, brushless, position sensor-less, stator-rotor double plastic-encapsulated motor or high-efficiency asynchronous motor or high-speed switched reluctance motor through maximum power point tracking, conversion and control devices. Water is lifted from the deep surface to the ground for farmland irrigation or human and animal drinking.
1. DC brushless solar water pump (motor type):
Brushless DC motor pump is composed of brushless DC motor and impeller. The shaft of the motor is connected with the impeller. There is a gap between the stator and the rotor of the pump. Water will penetrate into the motor for a long time, which increases the possibility of motor burnout.
Advantages: Brushless DC motor has been standardized, there are specialized manufacturers mass production, low cost, high efficiency.
2. Brushless DC magnetic isolation solar water pump:
Brushless DC pump uses electronic component commutation without carbon brush commutation. It adopts high-performance wear-resistant ceramic shaft and ceramic bush. The Bush is connected with a magnet through injection molding to avoid wear. Therefore, the service life of brushless DC magnetic pump is greatly enhanced.
The stator part and the rotor part of the magnetic isolation pump are completely isolated. The stator and the circuit board part are sealed with epoxy resin, 100% waterproof, the rotor part is made of a permanent magnet, and the pump body is made of environmentally friendly materials. The noise is low, the volume is small and the performance is stable. Various required parameters can be adjusted by the winding of stator, and wide voltage operation can be achieved.
Advantages: Long life, low noise up to 35 dB, can be used for hot water circulation. The stator and circuit board of the motor are sealed with epoxy resin and completely isolated from the rotor. It can be installed underwater and completely waterproof. The axis of the pump is made of the high-performance ceramic shaft with high precision and good seismic resistance.
IIIThree-phase AC pump is driven by a three-phase AC motor.
Unlike DC systems, solar AC pumps consist of the solar array (power supply), solar pumping inverters (converting DC to AC while controlling motor frequency) and three-phase AC motor pumps.
Advantages: The three-phase AC motor pump in the system can be replaced by the AC pump driven by the market electricity or diesel engine, and the compatibility is very good. At the same time, AC pumps break through the power limitation of DC pumps. The power can be applied from 150 to 105 kW, which is suitable for large areas of farmland, desert control, and irrigation.
1. Reliability: Long life, little use of moving parts in photovoltaic power supply, reliable operation;
2. Safety, no noise, low power consumption, and no other public hazards. It does not produce any harmful substances of solid, liquid and gas, and is absolutely environmentally friendly.
3. Simple installation and maintenance, suitable for unattended, especially for its high reliability.
4. Compatibility is good. Photovoltaic power generation can be used in conjunction with other energy sources. It can also make the photovoltaic system more convenient to increase capacity according to needs.
5. It is highly standardized and can be connected in series and parallel by components to meet the needs of different power consumption, with strong versatility.
6. Solar energy is available everywhere and has a wide range of applications.
7. It has a good long-term economy, especially compared with the common pumping of diesel engine, it has the advantage of overwhelming economy.