摘 要

电力系统动态物理模拟试验主要用于：（1）由于认知的局限性，当一些新的问题或物理现象无法完全用数学方程式描述时，物理模拟可以作为一种有效的分析手段对现象的本质及其变化规律进行探究；（2）物理模拟为电力系统的理论和计算公式提供了验证平台，使得理论进一步完善和发展；（3）新型继电保护和自动控制装置能够直接连接到物理模拟系统中，进行各种工况运行和短路故障实验，测试装置的各项性能指标。

目前，为满足继电保护和自动控制装置的测试需要，电力系统动态物理模拟系统额定容量一般为数十千伏安，其存在投资巨大、占地面积广、功耗高、噪声大等缺点。对于中性点不接地配电网的物理模拟来说，现有的物理模型一般由多个大额定容量的单电容配电线路模型、断路器模型、特制电压互感器和电流互感器模型以及短路开关模型等组成，结构复杂，且需要现场进行施工布线操作才能满足实验要求。费时费力，不利于配电网单相接地故障选线、故障消弧及过电压计算等研究的实验验证。

实际上，科研机构一般仅利用电力系统动态物理模拟系统探索电力系统新规律和校验理论分析结果，短路容量可以设计得非常小。

针对上述背景技术存在的问题和缺陷，本文借助印制电路板（Printed Circuit Board，PCB）设计中性点不接地配电网物理模拟系统，实现电力系统物理模拟的微型化、智能化和低功耗化。具体包括：分析与设计基于π型集中参数电路模型的配电线路PCB模块，以准确模拟配电线路的故障暂态特性；在此基础上，设计实现基于PCB板的中性点非有效接地配电网微型物理模拟系统；设计相应的电气量参数采样、处理与监测电路，实现微型动模实验平台电气量数据的实时处理、上传与监测；最后，制定一套完整地测试方案，对配电网单相接地故障稳态与暂态特性的理论分析结果进行测试与分析。

关键词：PCB板；微处理器；配电网；配电线路模型；微型动模实验平台

Abstract

The dynamic physical simulation test of power system is mainly used for: (1) Due to the limitations of cognition, when some new problems or physical phenomena cannot be completely described by mathematical equations, physical simulation can be used as an effective analysis method to the nature of phenomena. (2) Physical simulation provides a verification platform for the theoretical and computational formulae of the power system, so that the theory can be further improved and developed; (3) The new relay protection and automatic control device can be directly connected to the physical simulation system for a variety of operating conditions and short-circuit fault test to assess the performance of the device.

At present, the dynamic physical simulation system of power systems generally has a rated capacity of several tens kVA to meet the testing requirements of relay protection and automatic control devices, which has the disadvantages of huge investment, wide area, high power consumption, and large noise. For the physical simulation of ungrounded neutral distribution networks, the existing physical model is generally composed of several large-capacity single-capacitor distribution circuit models, circuit breaker models, special voltage transformers and current transformer models, and short circuits switch model and other components. It is complex and the construction and wiring operations on site are required to meet the experimental requirements. It is time-consuming and laborious, which is not conducive to the experimental verification of research on single-phase earth fault line selection, fault arc suppression, and overvoltage calculation in distribution networks.

In fact, scientific research institutions generally only use the power system dynamic physical simulation system to explore the new laws of the power system and verify the theoretical analysis results. The short-circuit capacity can be designed to be very small.

Against the problems and defects in the above background technology, this paper uses Printed Circuit Board (PCB) to design a physical simulation system for an ungrounded neutral distribution network to realize the miniaturization, intelligence, and low power of consumption the physical simulation of the power system. Specifically including: Analysis and design of distribution circuit PCB module based on the π centralized parameter circuit model to accurately simulate fault transient characteristics of the distribution circuit; Based on this, we will use PCB technology to design a micro-physical simulation system with neutral ineffectively earthed. Then, the corresponding electric quantity parameter sampling, processing and monitoring circuits are designed to realize the real-time processing, uploading and monitoring of the electrical data of the micro-dynamic simulation experiment platform; At last, we will draw up a complete test plan to test and analyze the theoretical analysis results of steady-state and transient characteristics when the single-phase earth fault of distribution network occurs.

Key Words：PCB board；Microprocessor；Distribution network；Distribution line model；the Micro-Dynamic Simulation Experiment Platform

目 录

第1章 绪论 1

1.1 课题研究背景及意义 1

1.2 国内外研究现状 2

1.2.1 配电线路模型的研究现状 2

1.2.2 微型动模实验平台的研究现状 3

1.2.3 PCB技术和微处理器的发展现状 3

1.3 本文主要研究工作及创新点 4

第2章 配电线路模型的研究 6

2.1 配电线路常用模型 6

2.1.1 配电线路的方程式 6

2.1.2 π型和T型线路模型 8

2.1.3 三相配电线路模型 9

2.2 综合计及稳态和暂态响应特性的配电线路模型研究 11

2.2.1 传统集中参数精确等值模型及近似等值模型分析 11

2.2.2 改进型集中参数等值π模型的构建 12

2.2.3 改进型集中参数等值π模型的验证与分析 14

2.3 适用于非有效接地配电网的三相配电线路模型研究 18

2.3.1 改进型三相配电线路模型的构建 18

2.3.2 改进型三相配电模型的验证与分析 20

2.4 本章小结 22

第3章 中性点非有效接地配电网的研究与等值电路设计 23

3.1 中性点非有效接地配电网运行特性研究 23

3.1.1 中性点不接地配电网运行特性 23

3.1.2 中性点经消弧线圈接地配电网运行特性 24

3.2 基于PCB板的中性点非有效接地配电网等值电路设计 25

3.2.1 中性点非有效接地配电网典型模型及其参数 25

3.2.2 总体结构及注意事项 26

3.2.3 断路器模块设计 27

3.2.4 三相配电线路模块设计 29

3.2.5 短路开关模块设计 31

3.2.6 其他模块设计 32

3.3 本章小结 32

第4章 微型动模实验平台电气量参数的采样、处理与监测 33

4.1 电气量采样方案 33

4.2 电压、电流传感器的选取 34

4.3 信号调理电路的设计 36

4.3.1 基于电压互感器的信号调理电路设计 36

4.3.2 基于电流互感器的信号调理电路设计 38

4.3.3 基于采样电阻的信号调理电路设计 39

4.4 零序电流获取电路的设计 40

4.5 主控板设计 42

4.6 本章小结 43

第5章 微型动模实验平台的测试与分析 45

5.1 测试环境及仪器 45

5.2 测试项目 46

5.3 测试结果与分析 46

5.3.1 基于电压互感器的信号调理电路测试与分析 46

5.3.2 基于电流互感器的信号调理电路测试与分析 48

5.3.3 基于采样电阻的信号调理电路测试与分析 49

5.3.4 零序电流获取电路测试与分析 50

5.3.5 微型动模实验平台单相接地故障测试与分析 51

5.4 本章小结 54

结论与展望 55

参考文献 57

附录A 部分MATLAB程序代码 60

附录A1 配电线路稳态阻抗特性仿真程序 60

附录A2 配电线路暂态阶跃响应特性仿真程序 61

附录B 部分芯片资料 63

附录B1 运算放大器OP07A资料 63

附录B2 运算放大器LM358资料 63