Research On Li-Ion Battery Energy Storage Power System With Voltage Drop Compensation

The high-voltage and high-power DC energy storage power supply system is an important device in electromagnetic emission and electromagnetic propulsion.Its performance research and development is of great significance to the development and application of electromagnetic emission technology.In this paper,based on the application requirements of high-power DC energy storage power supply system,using polymer lithium battery as energy storage medium,the design scheme of "lithium battery + Dynamic Voltage Regulation(DVR)internal resistance and line impedance compensation" is proposed,and the overall design of the energy storage power supply system is carried out and the control strategies are researched on.First of all,this paper designs the overall architecture of the lithium battery energy storage power supply system.For the common midpoint voltage,the power supply scheme generated by the electrolytic capacitor partial pressure has the disadvantages of large volume,heavy weight and poor reliability.The system series power supply scheme is adopted to improve the system reliability.The energy storage system consists of five parts: AC input control cabinet,lithium battery main energy storage cabinet,DVR compensation energy storage cabinet,DVR compensation cabinet and output control switch cabinet,and detailed design description of each cabinet.Finally,the simulation model of DC energy storage system is built to analyze the feasibility of the system design.The DVR module circuit is a very important part of the energy storage power supply system.The ten-fold interleaved parallel Buck structure is used in the topology to reduce the current stress of the device.At the same time,the parameters of the DVR circuit are calculated,selected and the main control board hardware design..For the traditional thermal analysis method,it is only suitable for the shortcomings of constant load and steady state.It is not suitable for the short-time triangular wave load of this subject.The ANSYS finite element analysis software is used for transient thermal analysis of IGBT and inductor in DVR module.In order to ensure that the IGBT and inductor temperature rise are within a reasonable range,prevent thermal failure and thermal damage of the device.The control strategy of the DVR of the lithium battery energy storage power supply system is studied.The single voltage loop and multi-current inner loop control mode are adopted.Multiple current inner loops constitute the current sharing controller to realize the parallel current sharing of the ten-fold circuit.The small-signal modeling of the DVR module's ten-fold interleaved parallel topology isdesigned to design the current inner loop controller and the voltage outer loop controller.The simulation analysis and experimental comparison of the current sharing controller are carried out to verify the current sharing effect and dynamic response performance of the current sharing controller for multiple structures.Finally,an experimental platform for energy storage systems is built to verify the stability of the main control board function and system control strategy.At the same time,a high-power working experiment was carried out on the DVR module circuit of the energy storage system to verify its stability under large voltage and high current conditions.