• Energy Research

A continuous change in the solar irradiance level and local atmospheric conditions, such as temperature and humidity, necessitate the use of maximum power point tracking (MPPT) technique of a photovoltaic (PV) system. MPPT ensures to harvest maximum power. Generally, voltage and current sensors are required to track the power of a PV system. The proposed method tracks the power of a PV system without the use of any current sensor. It not only reduces the cost of the system, but also reduces the communication burden, internal disturbances, and complexity. The proposed scheme estimates the current internally by using Luenberger observer technique. Thus, the estimated current is given to perturb and observe based MPPT technique, to generate the required duty for a dc–dc boost converter. The proposed scheme is experimentally investigated, and thus, obtained results are compared with well-established MPPT techniques. A comparison shows that the proposed system results are in a good agreement with the current sensor based MPPT technique.

AbstractThe photovoltaic (PV) power generation and cooling demand of the air conditioner are increased along with an increase in solar irradiation. Therefore, considering such fact, in this paper, PV power is integrated with the air conditioner to support the grid. With recent developments in power electronics, the air conditioning systems are operated in variable speed using variable frequency drive (VFD) technology. In this paper, taking the advantage of the VFD technology, PV power is directly injected into the DC bus of VFD using an isolated DC‐DC converter. In this methodology, due to the high‐frequency DC‐DC conversion, high power DC‐AC (50 Hz) stage is eliminated, and seamless power is transferred from PV generation to the load without interrupting the main operation of the air conditioner. Thus, the reliability of the system is enhanced with the reduction in overall cost, conversion losses and bulkiness. With the PV power support, the peak amplitude of the grid current is reduced and consequently the power consumption, reactive power intake from the grid, as well as the harmonics component of the grid current, are reduced. This scheme is used in rural or suburban areas where the solar profile is significant and air conditioner is extensively used.