Design And Implementation Of Program-controlled Excitation Power Source Based On DDS

Performance evaluation of the fuel cell plays a key role in ensuring fuel cell works efficiently and security, while excitation source is an important part of the performance testing system. In the research of resistance test system of the fuel cell and the Current Skin Effect on proton exchange membrane fuel cell, excitation source should provide sinusoidal wave, square-wave and triangle wave signals, and the excitation current should be large enough. Thus, a design of a excitation power source which can output various wave signals is getting more and more importance. The paper gives a design of excitation power source system which based on DDS technology to meet the demand for the fuel cell performance evaluation. The paper discusses the problem as below:This paper introduces the form and the principle of the excitation power source system which based on DDS technology, by analysing the requirements for the Fuel Cell Impedance Monitoring and The Research of Current Skin Effect on Proton Exchange Membrane Fuel Cell, further improves can be done to consummate the structure of the excitation power source system.Based on the theory of DDS, this paper designs the digital part in DDS structure and its interface with the MCU by using Quartus II development platform. And then designs the filter and programmable-gain amplifiers circuits, the signals pass through these circuits will become well and the waveform amplitude can be controlled. At last, the paper designs the Power Amplifier circuit to improve the load capacity of the system.In order to improve the operability and security, the paper designs the operate panel of the excitation power source system with Lab Windows/CVI. The operator can use the panel to control the excitation power source and get the status of the excitation power source.During the testing phase, the performance of the excitation power source fully achieves the design objective, so the excitation power source can fully satisfy the requirements for Fuel Cell Impedance Monitoring and The Research of Current Skin Effect on Proton Exchange Membrane Fuel Cell.