What is MPPT?

With the growing global demand for clean energy, the photovoltaic (PV) energy storage industry will continue to grow rapidly in the coming years. In the process of researching how to efficiently utilize PV energy, MPPT has become a hot word in the new energy industry in recent years.

1. Definition of MPPT

Maximum Power Point Tracking (MPPT) is an intelligent technology, which is one of the important factors affecting the power generation efficiency of PV power plants, and is used in PV power generation systems to automatically find and maintain the maximum power output point of PV modules under different environmental conditions (e.g., light intensity, temperature changes, etc.). This technology ensures that the PV panels can output the maximum electric power under any conditions, thus improving the efficiency and power output of the whole system.

2. Working principle of MPPT

The core principle of MPPT technology is to make use of the relationship between power and voltage and current, by continuously adjusting the output voltage and current of the inverter to match the maximum power point under the current light intensity. During this process, the inverter monitors the output power of the PV module in real time and automatically adjusts the output voltage and current according to the power changes to achieve the best working condition.

3. Key Technical Indicators

Conversion efficiency:  The effectiveness loss of the converter in the conversion process.

Response speed:  How fast the system reacts to external changes (e.g. light changes).

Stability:  The ability of the system to maintain stable performance under different operating conditions.

4. MPPT controller tracking method

Constant voltage method: simple to implement, the algorithm is easy to realise. However, the tracking accuracy is relatively poor, not necessarily the maximum power point.

Disturbance observation method: simple structure, few measurement parameters, easy to implement. There will be oscillations near the maximum power point, resulting in energy loss, and ‘misjudgment’ will occur.

Conductance incremental method: very good following, to ensure the maximum power output. The control algorithm is complicated, the detection accuracy is high, and the step size is not easy to choose.

5. How to select PV inverter MPPT quantity?

According to the different terrain of PV power station, component shading, choose different MPPT structure of PV inverter, reduce the purchase cost and maintenance cost of the power station, improve the economic efficiency.

• In the area of flat land with no shading and good light conditions, selecting a single MPPT, single-stage structure of the inverter can improve system reliability and reduce system costs;

• For hill power station and roof power station with not very complicated topography and no component shading, it is recommended to choose two-way MPPT multi-string inverter, which can take into account the string mismatch and high efficiency, and the design is more flexible. ADAYO POWER is committed to the solution of home energy storage, which is applicable to the two-way MPPT multi-string inverter.

• Complex terrain hill power station, there are generally inconsistent component orientation and local shading phenomenon, and different shading characteristics of different hills, which will bring component mismatch problems, then each MPPT 2 string input inverter will be a better choice, no fuses wearing parts, fault location accuracy is high, and maintenance is simpler.

The new energy storage industry is ushering in the trend. What is the future development direction and competitive landscape? Stay tuned to ADAYO POWER, we will continue to bring you the latest PV consulting.