Research On Key Technologies Of Arrow-borne Distributor Based On Powerlink

The power supply and distribution control,parameter measurement and fault diagnosis of the electrical equipment are mainly responsible for the rocket launching process.With the increase of the scale and complexity of the rocket equipment,higher and higher requirements are put forward for the bus data communication performance in the distribution controller.Because the traditional distribution system of carrier rocket usually uses CAN or 1553 B bus,the data throughput is low and the communication efficiency is low,which can not meet the requirements of real-time and reliability design of the system.Therefore,an arrow load distribution system based on real-time Ethernet Powerlink is designed in this paper.Firstly,the real-time communication technology of Powerlink is studied,and the two communication modes in Powerlink synchronization phase,namely the Preq/Pres mode and the Poll Response CHPRC mode,are compared by theoretical calculation.PRC is a communication mode with higher real-time performance,but the accuracy of transmitting time point from the slave station is a key factor affecting the stable operation of the system.Therefore,an accurate calculation method of transmitting time point is implemented by measuring the data transmission delay between the stations.In addition,a Powerlink network test system with one master and five slaves was built on Windows platform for verification.Based on PRC mode,it can run stably in 3.3ms communication cycle,1.5 ms shorter than the Preq/Pres mode.Secondly,in order to meet the real-time and reliability design requirements of the distributor,the architecture of "ARM + FPGA" is adopted.The processor of Powerlink protocol stack is embedded in the FPGA,and the external Ethernet chip is connected to the RJ45 interface to form the slave station of the distributor,which completes the functions of telemetry data acquisition,remote control instruction receiving and power distribution command output.Powerlink dual network redundancy is designed to improve system reliability.When a line is suddenly disconnected,the system can realize network switching in one cycle.The system can run 450 μs,and the distribution response time can reach 1.308 ms.In conclusion,the power supply and distribution mode based on Powerlink real-time Ethernet technology proposed in this paper can well take into account the relationship between real-time and reliability,meet the design requirements,and has reference significance for the design of rocket power distribution system.