Design And Implementation Of High Precision Closed-loop Source Generator

Signal source provides analog signal for acquisition equipment to analyze the external environment of missile and plays an important role in data acquisition system.Analog signal source includes slow variable signal source and fast variable signal source,wherein the slow variable signal source simulates the level signal of the sensor on the bomb,the fast variable signal source simulates the battery voltage signal on the bomb,and the switch command signal source simulates the command signal of the test equipment.The acquisition equipment analyzes the external environment of the missile by collecting the output signal of the source generator.The higher the signal precision of the signal source,the more accurate the simulated external environment of the missile.The rapid and slow simulation signal precision of the design is up to ±0.3%.Each board has the function of signal closed-loop detection,which improves the fault detection ability of the source generator.According to the functional requirements of the project,the source generator is designed.The whole equipment is composed of a test bench and a host computer,which are based on PCI bus for communication,man-machine interaction and signal transmission.FPGA as the core device to control the circuit work,according to the function of each module circuit design.Analog signal includes 96 channels of dc level slowly variable signal and 16 channels of rapid variable signal,rapid variable signal includes DC signal,AC sine wave signal and pulse signal.Switching signal includes 32 channels of active command signal and 6 channels of passive command signal,among which the active command signal consists of 24 channels of 28 V and 8 channels of 5V command signal.At the same time,it involves the substitution of the home-made source card,realizing the home-made design of slow variable signal source and passive switching signal source.By building a test platform to test and analyze the source generator,the source generator indicators have reached the design requirements of the task book,and has a certain engineering value,in the end successfully used in a model of the development task.