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On account of that common subsynchronous resonance controllers cannot well adapt to the time-varying and nonlinear characteristics of power system, biogeography-based optimization (BBO) algorithm is introduced to design subsynchronous damping controller optimally based on the mechanism of suppressing SSO by static var compensator (SVC). The simulatied results of Jinjie plant indicate that the subsynchronous damping controller optimized by BBO algorithm can remarkably improve the damping of torsional modals and thus effectively depress the multimodal SSO, ensuring the safety and stability of units and power grid operation.

A 2.45 GHz microwave-plasma chemical-vapor deposition (MPCVD) reactor was designed and built in-house by collaborating with Guangdong TrueOne Semiconductor Technology Co., Ltd. A cylindrical cavity was designed as the deposition chamber and a circumferential coaxial-mode transformer located at the top of the cavity was adopted as the antenna. Two quartz-ring windows that were placed far away from the plasma and cooled by water-cooling cavity walls were used to affix the antenna to the cavity and act as a vacuum seal for the reactor, respectively. This design improved the sealing and protected the quartz windows. In addition, a numerical simulation was proposed to predict the electric-field and plasma-density distributions in the cavity. Based on the simulation results, a microwave-plasma reactor with TM021 mode was built. The leak rate of this new reactor was tested to be as low as 1 &times, 10&minus, 8 Pa&middot, m3&middot, s&minus, 1, and the maximal microwave power was as high as 10 kW. Then, single-crystal diamond films were grown with the morphology and crystalline quality characterized by an optical microscope, atomic force microscope (AFM), Raman spectrometer, photoluminescence (PL) spectrometer, and high-resolution X-ray diffractometer. It was shown that the newly developed MPCVD reactor can produce diamond films with high quality and purity.

Solar energy is a kind of renewable energy, it‘s abundant, clean and environmental protection. In the current theme that calls for saving energy and reducing pollution, it’s undoubtedly of great significance to make full use of solar energy. In order to effectively use solar energy, we developed an automatic sunlight tracking solar panel system based on single chip microcomputer. We use MC9S12XS128 single chip microcomputer as the main control chip, and acquire signal with the sensor composed of photoconductive resistances. According to the signal collected by sensors, the control signal drives step motor to rotate, so that the system can follow the sun, ensuring that solar panel is always vertical to the sunlight, so it can absorb and convert solar energy to the maximum extent.

In order to solve the electromagnetic radiation problem of traditional computer mouse and computer keyboard, we disclose sets of new anti-radiation computer mouse and computer keyboard. These anti-radiation computer mouse and keyboard are specially designed in frame and enclosure. The mouse shell is divided into front and rear part, or segregated two enclosures by shielding board in mouse shell. The circuit of mouse is set in front part of the mouse. Left and right push-button and manual rollers are set in rear part of mouse. The control circuit of keyboard is detached from it and set in a card that can be plug in expansion slot of computer. Circuit is the source of electromagnetic radiation. Thus, the sources of electromagnetic radiation are far from your hand during your operation. Furthermore, by taking shielding and absorbing precautions, these new anti-radiation mouse and keyboard have hardly any radiation at all, no secret information will leak out, and will not do harm to your health. They have all the advantages of traditional computer mouse and keyboard, and much more than this, they are anti-radiation. These anti-radiation computer mouse and keyboard are green products, have no radiation to computer users.

In order to reveals the dynamic, nonlinear work process of three-phase SPWM inverter, simulation model of three-phase full bridge voltage source SPWM inverter was built. Typical figure of voltage, current and spectrum was given and analyzed. Figures include line voltage of load, phase voltage of load, neutral point voltage of load, source current wave, Fourier analysis, Total Harmonic Distortion of voltage and current, inverter input impedance, line to line impedance. This Simulation model and results can be used as auxiliary in teaching, scientific research and product development. This simulation model was intuitive, commutative, being able to display graphs dynamically. Using this simulation model in class, the difficult in teaching three-phase full bridge SPWM inverter will be solved, it can also advance students’ studying interests and strengthen their understanding and save class hours. This simulation model has important value.

After comparing with the shortage of traditional model notebook computers and desktop computers, we disclose sets of new anti-radiation notebook computers. They have all the advantages of traditional desktop computers and notebook computers. You can enjoy their portable, comfortable, excellent heat-spread, high reliability, modularized hardware, quality and cost effective. Much more than these, LCD Monitors of these new designed computers are set before cabinets, so the cabinets behind are far away from you during your operation, they can significantly reduce electromagnetic radiation to you. The radiation can be reduced to less than 10％ of its original level，by taking other precautions ,such as shielding and absorbing, these new anti-radiation notebook computers hardly have any radiation. Hence, these anti-radiation notebook computers are green products indeed, have no radiation to computer users, and much more accord with Human-Machine Engineering principles.

Natural diamonds from Liaoning and Shandong provinces, a HPHT diamond from Russia and a CVD diamond from the Element Six Company in America were selected as seed crystals for the growth of diamonds using the microwave plasma CVD method. The seeds and grown diamonds were characterized by FTIR, Raman spectroscopy, photoluminescence spectroscopy, XRD and AFM. Results indicate that the natural diamonds are type IaAB with a unique orientation and great differences in internal stress and crystalline quality. The HPHT and CVD diamonds are type Ib and type Ⅱa, respectively, with an angular deviation of 1-2.5 degrees and better crystal structure, and are more suitable for the CVD growth of single-crystal diamonds with little variation in internal stress and crystalline quality. The diamond layers grown on the natural IaAB seed crystals from Liaoning and Shandong provinces are polycrystalline with a serious lattice mismatch and impurities of microcrystalline graphite and amorphous carbon while the diamond layers grown on the HPHT type Ib seed crystal from Russia and the CVD type Ⅱa seed crystal from the Element Six Company are both of high quality. Moreover, the diamond layer grown on the CVD seed crystal has a narrower FWHM of the Raman peaks and a lower amount of non-diamond carbon impurity, indicating that it has a better crystalline quality than the diamond layer grown on the HPHT seed crystal.

Taking a certain regional power system in China for an object to be researched, a simple and easy way is proposed to model impulsive load, which can be integrated with BPA simulation software. That is, changing measured curves of impulsive load into a column form. With them, the influences of impact loads on the adjacent power plant generator units are simulated under three different operation modes. The results show that when the impulsive load is connected with power system, the larger the short circuit capacity of the connecting bus is, the little the impulse is.