The large-scale development of wind power is an important means to reduce greenhouse gas emissions, alleviate environmental pollution and improve the utilization rate of renewable energy. At the same time, large-scale non grid connected wind power generation theory avoids the technical difficulties of wind power integration [1]. However, due to the randomness and uncontrollability of wind energy, the output power of the wind power generation system will fluctuate accordingly [2]. Therefore, the corresponding energy storage devices are arranged in the non-grid-connected wind power generation system to ensure the power quality, and it has become the key to full utilization of renewable energy. In the case of wind speed fluctuation, the DC bus control strategy of the wind turbine is proposed in this paper. It can reduce the impact on the unit converter and the power load; this ensures safe and stable operation of non-grid connected wind turbines.

The problem of low vibration energy collection efficiency in the environment is the focus of the current piezoelectric power generation technology. In order to improve the collection efficiency of vibration energy in the environment, a key technology of piezoelectric power generation is studied, which can collect the vibration energy of multiple directions in the environment. Firstly, the mathematical model of piezoelectric cantilever beam is established by using the basic theory of piezoelectric power generation technology, and the vibration mechanics analysis of the piezoelectric cantilever beam is carried out. Then, the finite element simulation of the piezoelectric cantilever beam is carried out by using ANSYS, and the natural frequency is consistent with the ambient vibration/environment frequency; finally, multi-directional piezoelectric power generation device is made, and the theoretical analysis and experimental test are carried out. The experimental results show that the key technology of multidirectional vibration piezoelectric power generation can effectively improve the collection efficiency of vibration energy in the environment.

No abstract