These technology (multi-rotor WEs) are complex and difficult to control compared to conventional single-rotor turbines. The negative of this technology is that it contains a large number of mechanical components, which makes it expensive and costly during periodic maintenance 9. Also, the system based on multi-rotor WEs is more stable and is not affected by the wind generated between the turbines in the wind farms 10. In addition, the energy gain from wind in the case of multi-rotor WEs is greater than the energy gain from wind in the case of conventional single-rotor turbines. In recent years, a new technology of multi-rotor turbines containing 4 or 6 turbines has emerged to greatly increase the energy gained from the wind and to exploit the technology to a large extent to gain space for wind farms and reduce the cost of energy production and the use of traditional sources of energy. In multi-rotor WEs, it is possible to use two turbines rotating on the same axis and being at a distance, and we can find two turbines at the same point and rotating in the opposite direction, depending on the technology used. In addition, the use of multi-rotor WEs leads to a reduction in the area of wind farms and overcomes the winds generated by turbines in wind farms 12. Whereas the multi-rotor WE are a development of the single-rotor WE to increase the value of torque and mechanical energy required to rotate the generator 11. These types can be divided into two types: single-rotor WEs 6, 7, 8 and multi-rotor WEs 9, 10. In the field of WE, several types of turbines can be used to generate enough energy from the wind to spin a generator. Accordingly, if the wind speed is less than the limit in which the machine operates as an electric generator, the turbines are stopped. Therefore, these electric generators can operate as motors and become consuming electrical energy in this case, and this is not desirable. Induction generators are electrical machines that can operate as generators or as motors. As is well known, depending on the wind speed, the power generated by the generators changes. But among its downsides is that it is very sensitive to network disturbances due to the direct contact between the generator stator and the network, and the rotor-side excitation transformer has a limited power rating 5. The wind system that uses the AG is characterized by low cost and can be operated in the case of variable wind speed 4. Also, this type of generator has an attractive feature that distinguishes it from the rest, as it has less power loss and the variable speed operation with the excitation transformer is only 25–35% of the generator rating 3. Traditionally, the asynchronous generator (AG) is a type of electric generator that has become famous in recent years in the field of renewable energies, especially in wind energy (WE) due to its durability, ease of control, low cost, and low maintenance compared to other types 1, 2. Three different tests are proposed to study and verify the behavior of the designed DPC-SPI-GA strategy compared to the traditional DPC technique. Also, inner loops are not used in this proposed DPC-SPI-GA technique as is the case in the field-oriented control (FOC) technique, where the proposed system in this work is characterized by an integrated structure. In this proposed DPC-SPI-GA technique, we need to measure current and voltage to estimate the active power and the reactive power. Moreover, the pulse width modulation (PWM) technique is used to control the AG inverter due to its simplicity and ease of implementation. The direct power control (DPC) technique is used based on the proposed SC-PI-GA (SPI-GA) technique to control the AG-based MRWE system, where this new nonlinear control technique is used to achieve stable control characteristics under random changes in wind speed and to provide great robustness against modeling uncertainties. This work designs a powerful new nonlinear control technique using synergetic control (SC), proportional-integral (PI) controller, and genetic algorithm (GA) for multi-rotor wind energy (MRWE) conversion systems, whereby an asynchronous generator (AG) is used to achieve optimal energy extraction.
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