中文摘要：

提出了采用高级数据链路控制（HDLC）作为换流阀系统中控制主机与阀基控制单元（VCU）之间通信协议的应用方式。该换流阀系统为三级控制系统，在控制主机和VCU上采用现场可编程逻辑阵列（FPGA）实现了HDLC收发器模块，外接光电转换器，采用光纤通信。其中控制主机通过HDLC协议向VCU发送脉冲宽度调制（PWM）控制命令和定值参数等数据，VCU则通过HDLC协议向控制主机上传电流电压采样值和阀状态信息等数据。通过实际系统的运行测试，验证了HDLC协议在控制主机与VCU之间通信的可靠性、实时性，并使系统具有较高的数据吞吐能力和灵活的可扩展性。

英文摘要：

This paper proposes the application mode of using high-level data link control （HDLC） as a communication protocol between the control host and the valve control unit （VCU） in converter valve system. The converter valve system is a three layers control systems. The HDLC transceiver module is implemented by FPGA in control host and VCU, connecting with external optical transceiver and communicating by optical fiber. The control host downloads control commands, setting parameters and other data to the VCU via the HDLC protocol. While, VCU uploads the sample value of current and voltage, the status information of valve and other data to the control host through the HDLC protocol. Through the actual operation tests of the system, the results demonstrate that the HDLC protocol communication between the host and the VCU is reliability and timeliness, and the system has a high data throughput and flexible scalability.