Energy storage systems and power plants

Abstract

The invention discloses an energy storage system. The energy storage system comprises a supercharging device, an energy storage unit, a pressure energy conversion unit, a liquid storage tank and an electric generator. The supercharging device is provided with a hydraulic pump, a reversing valve, a conveying cylinder and a main oil cylinder. During energy storage, the hydraulic pump provides hydraulic oil for the main oil cylinder, the reversing valve controls the main oil cylinder to reverse, and under the combined action of the hydraulic pump and the reversing valve, the main oil cylinder drives a piston in the conveying cylinder to reciprocate. In the process, the volume of a cavity in the conveying cylinder changes periodically. When the volume is increased, liquid in the liquid storage tank is sucked into the conveying cylinder by the conveying cylinder. When the volume is decreased, the liquid is extruded by the piston and then extruded into a volume cavity of the energy storage unit, and finally energy is stored in the energy storage unit in the form of liquid pressure energy. When the energy is released, the pressure energy conversion unit converts the pressure energy of the liquid into mechanical energy, and then the electric generator is driven to work. In addition, the invention further discloses a power station with the energy storage system.

Description

technical field [0001] The invention relates to electric power production technology, in particular to an energy storage system and a power plant. Background technique [0002] For a long time, in order to meet the ever-increasing power load requirements, the electric power construction department has to build various power generation facilities according to the maximum load requirements. The continuous large-scale construction of power generation facilities has brought great difficulties to the power construction sector. During the low peak period of electricity consumption, the power generated by these power generation facilities far exceeds the actual demand, resulting in huge waste. [0003] In order to reduce waste, excess electrical energy is usually stored. Common energy storage methods include battery energy storage, pumped water storage, and electrolysis of water to produce hydrogen. However, these three energy storage methods have serious defects, as follows: [0...

AI Technical Summary

Problems solved by technology

[0004] 1) Battery energy storage is to convert electrical energy into chemical energy and store it through the chemical reaction inside the battery. However, the number of charge and discharge of the battery is limited, the service life is short, and the use and maintenance costs are high

[0005] 2) Pumping energy storage is to pump water from a lower position to a higher position reservoir through a water pump, and convert electrical energy into potential energy of water for storage. This energy storage method needs to be located near the water where the height difference is more obvious When building large-scale storage tanks and releasing energy, it is necessary to rely on hydroelectric power generation equipment to convert the potential energy of water into electrical energy; therefore, pumped energy storage requires relatively high site and equipment, long investment and construction periods, and is subject to geographical conditions. Obvious restrictions

[0006] 3) Hydrogen production by electrolysis of water is to decompose water into hydrogen and oxygen through electrical energy, convert electrical energy into chemical energy and store it in hydrogen, and when energy is released, hydrogen is burned in thermal power equipment to convert chemical energy into electrical energy; A flammable and explosive gas, the storage conditions of hydrogen are relatively harsh, so the construction and maintenance costs of storage facilities are relatively high

[0007] To sum up, for the field of electric power production, how to ensure the high efficiency, safety and low cost of electric energy storage and release process is still a difficult technical problem

Images