Research And Design Of Dual Channel Redundant Intelligent Servo Controller

Electro-hydraulic servo control system has been widely applied in both industrial control and automation, the level of its development has become an important sign to reflect the industrialization process of a country. As the brain of control system, servo controller coordinates the operation of each part, finishes signal sampling and input, controls algorithm calculation and controls signal output as well. As system function grows stronger and the field of application is broadened, uncertain factors in the external environment increases greatly as well. The input and output channels of the controller, which has a direct connection to the external environment, are the weakest parts to break down. In order to improve the reliability of system, the technique of redundancy, in this paper, is utilized for the system design, the main content include redundant controllers overall design, hardware design and software design.In redundancy design, use two sets of processor, complete the same control algorithm’s calculation and outputs current right result that arbitrated by the comparing module. The whole design is divided into dual DSP part and FPGA part. In dual DSP part, two DSP modules have same hardware construction. They share the same external clock signal, run the same algorithm program and connected to the FPGA with its unique external interface XINTF(external interface). The arbiter using FPGA is divided into three modules: two dual port RAM modules connect the two DSP, respectively, which exchange and store the system’s running status, working condition and comparison results of two DSP and one data processing module compares and processes data that transmitted from two DSP.The hardware design mainly contains circuit design of the power conversion, the input signal shunt, I/U and U/I conversion, input and output channel self-inspection, interface between DSP and FPGA, interface between two DSP and D/A converter.In the part of software design, this paper mainly completed the program design of A/D, D/A conversion module, self-inspection of input and output signal control, determining the on duty DSP, synchronous communication of two DSP, comparison and arbitrations. In the part of control algorithm, this paper integrates the advantages of traditional algorithm and advanced intelligent algorithm, implements optimized deviation- deviation rate algorithm. Simulink and Modelsim simulation tools are used to aid design.At last, through laboratory test data, the results showed that the dual channel redundancy servo controller is stable and reliable, control precise and has reached anticipating performance index.