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Based on the analysis of mathematical model of switched reluctance motor and the structure of drive system, position sensor model, power converter model, switched reluctance motor model and other models were established through Simulink module. Through a combination of these models, a system model of APC control was built. The simulation results show the stability of the control system, which provides a reference to physical system designs of such switched reluctance motor.

Based on the analysis of structure principle and drive system of switched reluctance motor, switched reluctance motor model has been established by Simulink moduel. By changing the parameter of turn-on angle in the model, the corresponding phase current was collected for comparative analysis. It's concluded that the larger the turn-on angle, the smaller the amplitude of linear increase of the current, which has provided an effective reference for physical design of four-phase 8/6 pole switched reluctance motor.

Closed-loop feedback control system consists of subsystems including control subsystem, data communication subsystem, measurement subsystem and master. Currently, each subsystem applies its own computer for packaging and the subsystems are integrated by cables, which leads to excessive large size of the system. Based on actual projects, in this paper, a kind of new technology, PXI bus technology, is introduced to solve the problem. PXI bus computer is a type of firm measurement and automation platform based on PC. PXI (PCI extension for Instrumentation) bus combines the electric bus characteristic of PCI (Peripheral Component Interconnection) bus and the ruggedness and modularity of CompactPCI bus with addition of professional synchronous bus that triggers the local bus between the bus and modules, which makes PXI bus one of the best buses at present. Research and development of a DSP servo control card based on PXI bus proves that closed-loop feedback control subsystem can be integrated into PXI bus computer with PXI bus technology introduced.

If the signal is sparse in a domain, according to compressive sampling theory, the amount of data can be greatly compressed while sampled in sub-Nyquist frequency. This paper proposed a compressive sampling system based on pseudo random filter, in which the sampled data is firstly extracted by a periodic random filter, reducing the amount of data, in the digital domain, and then through digital extracting produce multipath signals, multi-channel signals are used to get the spectrum information of signals. The design method of hardware system based on GC5016 and high performance DSP is introduced in this paper. The experimental results show that the periodic random filtering is easy to implement, and the digital extraction method achieves multi-channel data and avoids the design of analog multi-channel hardware. This method is effective and practical for the compressive sensing process of signals and is used for control of switch reluctance motor system.

As has been pointed out by compressed sensing algorithm, sparse signals can be sampled in sub-Nyquist rate by random modulation or random filter, which enables data compressed largely and possibility of high bandwidth signal process. In this paper, a compressed sampling system based on multiphase random filter is presented, in which the filtered signals by periodical random modulation in digital domain can be extracted in sub-Nyquist rate, then the spectrum information of original signals is reconstructed from multi-channel signals which are generated by multiphase method proposed in this article. This multiphase digital filter with high feasibility of implementation successfully lowers necessity of hardware which is required in multi-analog channel sampling systems. Simulation results demonstrate the validity and practicability of signal spectrum detection.

Because of the illumination adjustment problem of seedling cultivation in mini greenhouse, a closed-loop feedback control system is proposed to control illumination based on PWM in this paper. This system is composed of single chip, buck circuit, PWM circuit based on DC-DC, LED, feedback circuit of illumination collection, and LCD1602 display circuit. In order to achieve intelligent adjustable light source, The single chip output adjustable PWM to control the current strength to control the led illumination, and The illumination is instantaneously fed back to the single chip via a light sensor for processing to meet the different illumination requirements of each growth stage of the plant. The system proves that the design can solve the illumination control problem in mini greenhouse, and it has real-time feedback and adjustment function.