The Ship Main Propulsion Redundancy Control System Based On Can Bus

With the development of economic globalization, the demand for ships and marine grows steadily. Requirements that domestic shipbuilding industry should be bigger and stronger have been present in Twelfth Five-Year Plan, while the current status of "just-made housing, equipment imports" which domestic shipbuilding industry has formed doesn't match Twelfth Five-Year Plan clearly. Main propulsion control system, as the core part of the ship automation system, is the marine equipment with high value-added. At present, the main propulsion control system is basically monopolized by foreign manufacturers, so research for ship main propulsion control system is imperative.This paper aims to develop a ship main propulsion control system with independent intellectual property rights. Firstly, this paper compares and analyzes the domestic and foreign research status of main propulsion control system, then proposes hot standby system platform structure and fully redundant parallel bus architecture, then determines the hardware and software design. Secondly, this paper builds a hardware platform and establishes a communication network system based on CAN bus. Finally, this paper makes experimental verification about the established hardware and software system. The main contents of this paper are as follows:(1) CAN bus technology. This paper firstly compares and analyzes several common field bus to obtain the advantages of CAN bus, secondly describes the relevant specifications about CAN bus technology.(2) The overall system design. This paper firstly designs the function of PCU, ECS, ACS and BCS operating stations in main propulsion control system, secondly designs the hardware platform architecture and platform redundancy, finally designs the software architecture and bus redundancy. The main propulsion control system hardware platform designed in this paper adopts hot standby mode via 232 serial bus. CAN bus adopts a folly redundant parallel program that both buses simultaneously work.(3) Building system hardware platform. In this paper, the main controller of hardware platform uses STM32F407, the system using an isolated power supply, redundant CAN bus using isolation transceivers and termination resistors split design, low-level device I/O processing module including analog acquisition and output circuits, digital input and output circuits. Analog acquisition circuits uses ADS8332, analog output circuits using AD420, digital input circuits using analog acquisition mode, digital output circuits using relay output mode. The branching processing circuits of all I/O terminals use analog switch ADG619.(4) Establishing system software platform. This paper designs the application layer, intermediate layer and physical layer in software structure respectively. Application layer design includes control logic, CAN bus application layer, redundant control node switching mechanism and the man-machine interface; middle layer design includes analog to digital conversion process and digital to analog conversion process; physical layer design includes CAN bus basic communication program.(5) Experimental verification. Experiments including power on self test, real-time communication, CAN bus fully redundant parallel program and control node hot standby program have been made on the hardware and software platform set up in this system. The results show that:the scheme for main propulsion redundancy control system is reasonable.