Theoretical Analysis of the Operation of a Multi-Unit Wind Power Plant in Conditions of a Shortage of Wind Power

Abstract

It is possible to use low-potential wind energy for the efficient operation of a wind power plant and for increasing the Annual Energy Production for guaranteed power supply to facilities in remote rural areas with a shortage of wind power. Currently in the development of large wind power plants worldwide hydraulic transmission is used to increase reliability and reduce the cost. However, the efficiency of such systems is lower than the efficiency of systems with a mechanical transmission (gearbox). But in regions with a shortage of wind power, wind power plants with a gearbox are not effective, and a hydraulic transmission could provide an increase in the Annual Energy Production of small wind power plants. Proposed is a small multi-unit wind-driven power plant with a hydraulic drive and an accumulator for power supply to remote facilities in rural areas. Methods for calculating the parameters and modes of operation of a multi-unit wind-driven power plant have been developed. The operation of a multi-unit wind-driven power plant was studied in the range of wind speeds of 4–14 m/s. The results of the theoretical analysis of the operation of the multi-unit wind-driven power plant are presented in the form of torque, rotational speed, power and flow rate diagrams. The results showed that the sum of flow rates of several pumps in the hydraulic system can provide the required constant flow rate of the hydraulic motor in a wide range of wind speeds. Thus, even at low wind speeds of 3–4 m/s on a typical day for a region with an average periodic wind speed of 4.3 m/s the total daily flow shortage is 75.2 L/min, while the total daily surplus is 180 L/min. The above calculation methods allow for a comparative analysis of the parameters, as well as the selection of design for the multi-unit wind-driven power plant being developed. The use of a hydraulic system with a hydraulic accumulator and several wind-receiving devices of different parameters, connected in parallel, significantly increases the efficiency of a small wind-driven power plant in a region with low-potential wind energy. In this case, the efficiency of the electric generator of a wind-driven power plant will always be maximum, since a constant rotational speed of the generator shaft is maintained and optimal generator modes are provided.