Advanced Materials Research Vols. 1008-1009

Abstract: In 2013, China Southern Power Grid (CSG) installed three ±200Mvar STATCOMs on the 500kV substations which are adjacent to the receiving ends of multiple HVDC lines. Based on the project of STATCOM test in CSG, the ±200Mvar cascaded STATCOM simulation model is established in the real-time digital simulator (RTDS) ,the aim is to study the modeling technology of H Bridge valve group by using small time-step and main control strategy .Amounts of tests has been done to verify the validity of the cascaded STATCOM model in different control modes. The RTDS STATCOM model also tested in the closed-loop CSG power network and the transient state response characteristics has been compared with real STATCOM control and protection devices for engineering prototype to verify the feasibility of the model. The constructed model has been successfully applied on the analysis of impacts on AC/DC paralleled CSG with STATCOM using RTDS.

Abstract: Numerical calculations with time dependant one-dimensional fluid model are performed at various conditions in argon atmospheric pressure to calculate electrical characteristics and plasma parameters including charged and metastable molecules densities. The simulation results show after steady discharge are formed, the voltage of discharge gap nearly remain constant and the phase is 0.36π advance of the applied voltage; The current density are in the same period as the applied voltage, the phase is 0.58π ahead of the applied voltage; The steady state Ar are in high number density in the whole discharge gap; The Ar* number density appear peak at the middle of the discharge gap; The Ar⁺ number density appear peak in the negative bright area.

Abstract: TMS320F2812 was taken as the main controlling chip, MOSFET was taken as the inverter switching device and IGBT was taken as the chopper switching device in the system. This paper introduced the main topology circuit design and circuit components selection.In the process of heating, double-closed loop control strategy fuzzy and DPLL (Digital Phase Locked Loop) was adopted. The simulation model of induction heating power system was built in SIMULINK platform. The simulation results indicate that the load frequency automatic tracking and closed-loop power control are realized. The time to steady output is about 0.1ms. Finally, built the 10kW/100kHZ induction heating power supply experimental platform, As can be seen from the experimental waveforms, the equivalent impedance of the load can always be weakly perceptual state.

Abstract: Aimed at the fault diagnosis and prediction of automobile engine, firstly designed a framework structure of automobile engine fault diagnosis and prediction system, and built a hardware platform; Secondly adopted the genetic algorithm neural network to fault prediction and diagnosis reasoning; Finally after analyzing automobile exhaust components, engine vibration, engine abnormal sound parameters, inferred the appeared and impending fault of automobile then made the tips for users on the screen. The results show that the performance of system is well, the accuracy of diagnosis and prediction is 95% in different conditions of experiment and debugging.

Abstract: Various field bus protocols come up with the development of technology, each device manufactures are using their own way to managing assets in their assets function managing systems, the shortage of this self-enclosed solution is self-evident. Users are looking forward to more and more functions realized by filed device, thus the devices linked into field bus are getting more and more complicated. To echo this needs, FDT/DTM technology is used in process of developing device managing system. FDT technology is one truly liberal technology, users could easily transfer device data into useful information, beyond the influence of their filed bus protocol, device vendor, as well as the device type, to realize supporting various field bus in one system.

Abstract: In order to achieve precise speed control for cutter suction dredger cutter motor, the controller should adapt well to uncertainties, such as geological environment, water flow, mechanical disturbance, etc. It makes the design of cutter motor controller always a hard work. This paper proposes an active disturbance rejection controller (ADRC) approach for cutter suction dredger cutter motor variable frequency drive system. Firstly, the LabVIEW platform was established by virtual instrument technology, which collected operating data of cutter motor in fundamental wave and total harmonic distortion (THD). Then cutter motor motion mathematic model was built and the ADRC design method was introduced. Lastly, the simulation results in the cutter velocity control and disturbance environments were done. The results show that the ADRC controller has strong robustness, and the precise speed control can be implemented.

Abstract: In order to control the temperature of Antiseptic Machine, the temperature control method based on fuzzy theory is presented. A program of temperature control system based on fuzzy theory is designed.The program transmits the temperature signal which is got from DS18B20 to TA89S52 and then transmits the control signal to AD421. The purpose is to control the corresponding solenoid valve work so that the Pakistan antiseptic machine’s temperature can be controlled. The test result indicates that the structure of the control system is simple and effective. The proposed method can overcome the object’s pure time delay characteristic with fast response and small overshoot.

Abstract: The article realization of NAND FLASH control glueless interface circuit based on FPGA,comparing the advantages and disadvantages of the NAND Flash and analysising the function of control interface circuit. The control interface circuit can correct carry out the SRAM timing-input block erase, page reads, page programming, state read instructions into the required operation sequence of NAND Flash, greatly simplifies the NAND FLASH read and write timing control. According to the ECC algorithm,the realization method of ECC check code generation,error search,error correction is described.The function of operate instructions of the NAND Flash control interface circuit designed in this paper is verified on Xillinx Spartan-3 board, and the frequency can reach 100MHz.

Abstract: According to the change of resistivity and magnetic permeability of iron load which will influence the resonance frequency in the process of induction heating, this paper presents a frequency tracking system based on the 74HC4046. It can control the output frequency of the power supply in real time, and make the power output frequency to trace the resonance frequency of load. This paper also analyses the phase compensation of the control system, and proposes a new way of phase compensation. The corresponding simulation experiment is done finally. It provides the theory basis to analyze and design an inverter power supply.

Abstract: A design of single precision floating point adder based on FPGA is presented,by analysing the form of real number formed on IEEE 754 and the storage format of IEEE 754 single-precision floating point,the addition arithmetic process which is easy to realized by using FPGA is put forward,the split of module based on the arithmetic process facilitates the realization of pipeline designing,so the single precision floating point adder introduce by this paper has powerful operation process ability.