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血液透析机是用于对终期肾病患者进行血液净化处理的医疗设备，在临床治疗中具有广泛的应用需求。随着电子技术的发展与医疗技术的进步，血液透析逐渐向着精准化、人性化、高安全、多功能的治疗模式发展，这对于血液透析设备的功能和性能都提出了更高的要求。而目前我国高端血液透析机主要依赖于进口，国产透析设备只能实现最基本的透析过程，智能化程度和安全性水平都亟待提升。因此研制适合中国国情的高端血液透析机对于提高国内的医疗技术水平、降低医疗成本具有重要的意义。

本文以提高血液透析机的整体控制性能为目标，开展控制系统设计和控制方法研究工作。通过透析机专用系列硬件模块设计，形成控制系统的模块化集成解决方案；通过组件化功能软件的开发，形成透析机的开放式控制软件体系；通过对透析液流量、电导度、温度等控制方法的研究，突破透析过程核心关键技术。论文的主要工作如下：

1、在充分分析现有血液透析机工作原理和控制流程的基础上，本文确定了新型透析机系统的硬件设计方案，采用模块化的结构形式，由多个处理器共同完成透析机的信号采集与控制。通过模块化的硬件单元设计，形成具有不同功能的透析机控制模块，提高了系统配置的灵活性和可维护。

2、基于不同嵌入式操作平台，本文分别开展了下位机逻辑控制和上位机人机交互与逻辑处理的软件开发工作。逻辑控制软件以面向功能任务的软件架构为基础，采用μC/OS-II操作系统，分别针对数据采集、设备通信、安全监测、流程控制等任务开发了相应的软件组件，通过组件在线配置逻辑实现运行过程中任务功能的动态组合。人机交互与逻辑处理软件采用面向功能任务的进程交互的软件构架，采用Linux-3.5操作系统，分别针对人机交互、逻辑处理、外设通信三个任务设计独立程序，通过进程间通信实现人机交互和透析流程管理。

3、在透析机能够实现透析流程的基础上，本文分别对透析过程中流量、电导度、温度的控制方法开展研究。针对透析流量难以测量的问题，本文设计了利用平衡腔体积不变逆向求解实际流量的方法，实现了流量反馈调节控制；针对透析液电导度在泵运转过程存在的波动问题，本文采用了柱塞泵相位记录机制，避免了相位误差，实现了电导度的控制；针对具有较大时滞、多干扰因素的透析温度控制问题，本文设计了能量模型预测控制方法，有效避免了建模偏差和外部干扰，实现了透析温度的精确控制。仿真和实验验证了这些控制算法的有效性和正确性。

Hemodialysis machine is a kind of medical equipment for blood purification, which has been widely used in clinical treatment. With the rapid development of electronic technology and medical technology, hemodialysis is developing toward the direction of precision, humanization, higher safety and multifunctional treatment modes, the function and performance of hemodialysis machine have been put forward for higher requirements. At present, China's high-end hemodialysis machines mainly rely on imports, domestic dialysis machines can only achieve the mostly basic dialysis processes, the level of intelligence and security are urgently needed to been upgraded. Therefore, the research of composite functional hemodialysis machine is of great significance to improve the level of medical technology and reduce the cost of medical treatment.

In order to improve the overall control performance of the composite functional hemodialysis machine, the design of control system and research on control methods are studied in this paper. Through the design of a dialysis machine's special hardware modules, this paper has get integrated solutions of the control system. Through the software development in components, the opening control-software system has been formed. Through the research of control methods about dialysate flow rate, conductivity and temperature, the key-performance indicators of the dialysis process have been controlled. The main work of this paper is as follows:

1. Based on the full analysis of the existing principle and control process of hemodialysis machines, the hardware-designing scheme of the new system in the dialysis machine has been completed. Its structure is designed for distributed structure and taking more than one processor to complete the signal acquisition and control functions. Through the modular designs of the hardware unit, the control module with different functions is formed, which has improved the flexibility and maintainability of the system.

2. Based on different embedded operating platforms, the software development of the logic control in the lower computer and the human-computer interaction with logic processing in the host computer was carried out. The logic control software, oriented with the software architecture facing functional task and based on the μC/OS-II operating system, was developed into corresponding software components for data acquisitions, equipment's communication, safety monitoring, process control and other tasks. It is through the logic task of component's online-configuration to realize the dynamic organizations of operation processes. The software of human-computer interaction with logic processing was oriented on the architecture facing functional task and interacting processes. It is basing on the Linux-3.5 operating system and independly designed for human-computer interaction, logic processing and peripheral communication, which are through inter-processing communications to achieve human-computer interaction and the management of dialysis processes.

3. Based on the realization of basic dialysis processes, this paper carried out research on control methods about the three key parameters: flow, conductivity, temperature in the process of dialysis. For the problem of flow measurement, the scheme of reverse solution for the actual flow rate through the balance cavity's volume was designed and realized feedback adjustment and control to the flow rate. For the problem of fluctuations in dialysate conductivity, the design of phase record mechanism of piston pump has avoided the phase error and realized the control of dialysate conductivity. For the problem of dialysis temperature control with large time delay and multiple interference factors, an energy model predictive control method is designed, which can effectively avoid the modeling error and external disturbances and realized the accurate control of the dialysis temperature. Simulations and experiments verified the effectiveness and correctness of these control algorithms.