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A single electric water heater’s physical model based on first-order constant coefficient differential equations is constructed in this paper. An electric water heaters’ polymerization model is constructed based on the Monte Carlo method, and the error analysis is performed on the polymerization model. The influence of changing conditions on the frequency regulation response of the demand side of electric water heater is analyzed. The simulation results show that the electric water heaters can respond to changes in the frequency of the power system by adjusting their temperature setting point to provide a consider-able amount of frequency backup capacity.

Compared with traditional frequency modulation methods, if a reasonable control method can be adopted, load-side frequency modulation has the advantage of low cost. Air conditioning is a typical high-power household temperature-controlled load. The huge number and outstanding energy storage characteristics make it an important part of demand response and power system frequency modulation. This paper proposes a clustering and equivalent replacement method for air-conditioning load based on K-Means clustering algorithm. Based on the classification algorithm of air-conditioning load, a control strategy based on K-Means clustering algorithm for air-conditioning load participation in secondary frequency modulation of the system was proposed. Aiming at the phenomenon of “secondary peak load” in the process of load recovery in traditional control strategies, the time-sharing grouped frequency modulation control strategy is proposed. The simulation proves the effectiveness of this control strategy in eliminating the “secondary peak load” phenomenon.

Based on the method of space state, state division of household temperature-control load group is proposed. State sequence method is used to analyze the influence of load group abundance on aggregated power. Based on the minimum cost and maximum flow algorithm, the temperature-control load group’s abundance recovery strategy is proposed, which could achieves the goal of fast and smooth recovery load group abundance. The simulation of household temperature-control load respond to the power system primary frequency adjustment is carried out under the circumstances of good abundance, excess abundance and lack of abundance. The simulation results show that the effect of temperature control load on the power grid primary frequency adjustment is fine. and the effectiveness of the proposed frequency adjustment control strategy is verified.

In this paper, the hardware and software experiment system of the large angle maneuver of the satellite attitude is designed and realized according to the requirement of the professional construction. The composition includes: single axis turntable, a nitrogen source, the new DSP controller, model simulator, router, multi-channel rechargeable power supply system and battery, fiber optic gyro, flywheel, jet system, computer and printer etc. Attitude maneuver control method is PD control. The controller uses DSP SEED-DEC28335. The control experiment program is developed by using C language. Its research characteristic is to realize the wireless data communication between PC and DSP. The CCS compiler v5.5 and the operating system Windows 8-32 bits. The experimental results show that the large angle attitude maneuver simulation of the satellite based on flywheel is accomplished. The rotating angle range of the turntable is ±90 degrees. The accuracy of maneuver is less than 0.5 degrees and meet the simulation mission requirements.

Adiabatic fixed-bed reactor has proven commercially successful in large scale production of catalytic dehydration of methanol to dimethyl ether. A one dimensional pseudo-homogeneous model of an industrial reactor of dimethyl ether synthesis has been established. To verify the proposed model, the simulation results have been compared to available data from an industrial reactor. A good agreement has been found between them. The distribution of the catalyst bed temperature and concentration of each component was obtained under conditions of inlet temperature 260°C, reaction pressure 1.2MPa and gaseous hourly space velocity 950.7 h-1. With inlet catalyst bed temperature 240-280°C, operating pressure 0.6-1.8MPa and gaseous hourly space velocity 831.8-1069.5 h-1, the influence of these reaction conditions on temperature distribution of the reactor catalytic bed, outlet methanol conversion and the dimethyl ether yield were calculated. The results show that, with the rise of inlet temperature (240-280°C) and operating pressure (0.6-1.8MPa), the outlet conversion of methanol, the hot spot temperature and the DME yield increased. The increase of gaseous hourly space velocity (831.8-1069.5 h-1) leads to a decrease in the hot spot temperature of catalytic bed and the outlet conversion of methanol. But the DME yield rise initially and then descend.

The production processes included catalytic dehydration of methanol in an adiabatic fixed-bed reactor and two columns product separations. In this study, the technological process for dimethyl ether (DME) synthesis is built on PRO/II platform based on the combined parameters of the reaction dynamic model for methanol dehydration reaction, the improved NRTL model of the liquid phase, the PR model of vapor phase. In order to validate the proposed model, the simulation results have been compared with the available data from a set of industrial production equipment with a production capacity of 200 000 tonnes per annum. A comparison between the calculated and measured results has proved that these results are satisfactory. The bed height and the volume of the catalytic bed are calculated aim at one million t/a DME yields and while taking account of high-purity DME production. After discussing the influence of feed stage location and reflux ratio for DME product purity, the suitable unit operation conditions are chosen. Accordingly, accurate process simulation results provide the basis and guidance for an improvement and development of the similar industrial device.