Duan Zhengang

Design of MPPT algorithm under partial shadows

Owing to the complexity of the photovoltaic system structure and their environment, especially under the partial shadows environment, the output characteristics of photovoltaic arrays are greatly affected. Under the partial shadows environment, power-voltage (P-V) characteristics curve is of multi-peak. This makes that it is a difficult task to track the actual maximum power point. In addition, most programs are not able to get the maximum power point under these conditions. In this paper, we study the P-V curves under both uniform illumination and partial shadows environments, and then design an algorithm to track the maximum power point and select the strategy to deal with the MPPT algorithm by DSP chips and DC-DC converters. It is simple and easy to allow solar panels to maintain the best solar energy utilization resulting in increasing output at all times. Meanwhile, in order to track local peak point and improve the tracking speed, the algorithm proposed DC-DC converters operating feed-forward control scheme. Compared with the conventional controller, this controller costs much less time. This paper focuses mainly on specific processes of the algorithm, and being the follow-up basis for implementation of control strategies.

Design and Implementation of the Ground Source Heat Pump Remote Monitoring System

In this paper, the composition of the remote monitoring system, ground source heat pump process flow, remote monitoring data and the comprehensive economic indicators are designed and analyzed with focusing on the mathematical model of economic indicators and data processing method. Through the WebAccess configuration software, it realizes the real-time monitoring of heating/refrigeration (winter and summer) systems and two economic indicators which are the energy efficiency ratio of heating/refrigeration system and the energy efficiency ratio of the hot water system can be calculated by day, week and month. Based on .NET platform, the test results show that the data-processing method of the remote monitoring system can process and analyze the provided data, and also can provide an efficient, reliable basis for the model of renewable energy model construction.

Versatile PSIM Simulation Model for Photovoltaic Array with MPPT Function

A Versatile simulation model for photovoltaic array is developed based on the DC physical model of photovoltaic (PV) module under PSIM environment. The I-V, P-V characteristics of photovoltaic array with different combina-tions can be simulated by the model. In addition, the model includes the function of Maximum Power Point Tracking (MPPT) and completes the simulation of the perturbation and observation method. It is concluded from the analysis of simulation results that high accuracy of the model simulation can accurately reflect the physical characteristics of the photovoltaic, and will provide a basis for the simulation of the power generation systems.

Design and research on data analysis platform of the renewable energy monitoring system

This article is based on the research of the software which is used in present to analysis building energy consumption. Through long-term monitoring the renewable energy consumption in construction which located in different climatic zones, different resources zoning, and different building types, we build new software which is suitable for China. By using XML data exchange mode, the software can solve the heterogeneous data problems. Adopted with a decision system which has three bases, the software can solve many problems, such as the fusion of multiply monitoring points, energy types and model methods. Through providing renewable energy consumption formula, the software can calculate and compare renewable energy use efficiency between various kinds of architectural climatic zoning, and then help government to make decision.

Application of the Advanced Encryption Standard and DM642 in the image transmission system

AES encryption algorithm and digital signal processing (DSP) technology are used in image encryption transmission system to make sure the information security and confidentiality in this paper. The basic principles, structure of the algorithm and design skills are introduced and analyzed. The program design is realized in DSP environment. An overall scheme of the image encryption transmission system based on the DM642 platform is given and the DSP program design process is explained. The AES encryption running speed of image encryption transmission system in CCS environment is tested as well. Experimental results show that AES encryption algorithm and DSP technology can be applied to the real-time and secure image transmission.

Design of Three Phase Network Parameter Monitoring System based on 71M6513

In this paper, the design process of Three Phase Network Parameter Monitoring System is analyzed and the overall research scheme and design idea of the system are expounded. This paper mainly studies how to improve the accuracy of input voltage and current. The front-end voltage decreasing, current dropping circuit and remote data transmission circuit are designed. The programs of the data acquisition and calculation are made, real-time detection of power network parameters, energy calculation and the remote data transmission are achieved. Based on .Net platform, the host computer software is designed to receive the data and store them in the database, the mean value of power and energy parameters are calculated by the day, the week and the month, which are available to the user for inquiry. Many parameters such as three-phase voltage, three-phase current, frequency, active power, reactive power and voltage harmonics, can be detected by the system, which will provide a reliable basis for power quality analysis.

Research and Design of the Blood Coagulation Process Detection System

The medical value of coagulation process curve detection of a blood coagulation analyzer is analyzed. The fundamental principles of scattered light method for measuring coagulation curve is introduced and the corresponding photoelectric conversion device and the optical signal detection system based on C8051F040 are designed as well. The design process of detection system is also presented in detail. With the system using the unipolar low voltage power supply op amp MCP602 and multiplexer ADG608, the whole detection system is simple, reliable and embodies a good practical value. Experiments show that the design has the advantage of high accuracy and a good real-time property, which entirely meet the requirement in actual measurement.

Sewage-source Heat Pump Based on WebAaccess - Remote Monitoring System

This paper proposes a design about sewage-source Heat Pump - Remote Monitoring System based on Web access internet configuration software. The main purpose of this design is to achieve the remote monitoring device parameters, and provide data reference for a comprehensive evaluation of technical indicators of Sewage source heat pump system. The article analyzes the process flow of sewage source heat pump system, and elaborates overall framework for remote monitoring configuration software based on Internet Web Access sewage source heat pump system, and discusses a monitoring data processing method and some system comprehensive evaluation Indicators. The design of the renewable energy heat pump system based on Web Access software, which shows that this new integration technology is very useful to reduce the consumption of traditional energy sources, improve energy efficiency.

A design of monitor terminal for urban water supply base on LPC2210

To implement the informatization management of water supply pipe network, the paper introduces the general design of a wireless monitoring system for water supply pipe network based on ARM and GPRS technology, including the implement of the hardware and software of the monitor terminal. The monitor terminal was designed based on LPC2210 MPU and could collect the data of supply pipe network such as hydraulic pressure, water level, water flow and various electrical parameters. The data acquisition module based on STC89C51RC could collect analog data such as hydraulic pressure and water flow. The communication protocol based on GPRS and winsock network programming technology was designed. Experiment result shows that the system could realize functions including real time data acquisition, processing, wireless transmission and remote monitoring on GPRS service platform.