The Development Of Converter Energy Feedback Unit

With the development of the society, energy shortage problem has become more serious, in order to alleviate the energy problems and realize sustainable development strategy, motor system energy-saving projects has been listed as one of the ten focus on energy-saving projects by the national development and reform commission. At present, in the industrial frequency conversion motor drive system, for the superior motor control performance of the converter, the converter gradually become the standard configuration of many industrial equipment, and brought considerable economic benefits to the enterprise and the user, it has a huge market space. Although using the converter is better energy saving effect than other way on regulating speed, but the speed regulation system in the process of motor brake will inevitably generate electricity, the traditional converter doesn’t have the ability to use the renewable electricity, and consumed by braking resistor, and wasted this part of energy. An converter energy feedback unit has been designed in this paper to making use of that renewable energy, and making the speed control system to achieve a better energy saving effect.The research and development situation of the converter energy feedback technology, which are at home and abroad, has been analyzed in this paper, the working principle of the converter energy feedback unit control system has been introduced. The indirect current control mode and direct current control mode have been analyzed and compared, and based on the synchronous rotating coordinate transformation of fixed switching frequency direct current control technology be used in converter energy feedback unit control system. Converter energy feedback unit control system mathematical model has been established, the simulation model of fixed switching frequency SPWM direct current control has been set up and carried on the analysis by using Matlab/Simulink, finally by using of the powerful operation ability and the interrupt processing capacity of TI’s C2000 series DSP(TMS320F28062) chip, an converter energy feedback unit has been developed. Design mainly includes the hardware part and software part of the converter energy feedback unit. This paper mainly introduces the core hardware circuit design of the energy feedback unit, include: the main circuit, grid voltage detection circuit, the output current detection circuit, DC bus voltage detection circuit, IGBT drive circuit, protection circuit and other circuits. The modular software programming ideas has been introduced, the software function, main program and the core control algorithm implementation process have been described in detail in the software part. Finally the designs for the converter energy feedback unit proved correct and feasible through the test and waveform analysis. Eventually the converter energy feedback unit in the test site could operate reliably and stably, has reached the design goal.