Comparison of the evaluation between HollySys and Zhejiang University SUPCON DCS systems

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Comparison of the DCS systems offered by HollySys and Zhejiang University Zhongkong: Zhejiang University Zhongkong promotes its Web Field JX-300XP, while HollySys promotes its HOLLiAS MACS. In terms of hardware, the main controller used by HollySys features a redundant configuration, a single-CPU design, and industrial-grade embedded chips. Power-loss protection function, seamless switching function. Modular design; the main controller supports hot-swapping; cage-style fanless design. System network, control network, master-slave control, operational fault indication and diagnostic functions. External master control address setting function. Panel system program reset function. Online manual master control switching function. Zhejiang Supcon: redundant configuration, master-slave CPU design, industrial-grade embedded chips. Power loss protection function, seamless switching function. Patch-style design; the main controller does not support hot plugging; board-type fanless design. Fault alarm or reset, operation of active cards, active/standby status, ready status, operation of standby cards, communication status of Communication Network Port 0, communication status of Communication Network Port 1, operation of the Slave CPU, and indicators for network communication and I/O sampling operation. I/O cards: Zhejiang Supcon. There are data forwarding cards between the main controller and the field I/O; all cards are surface-mounted and designed as circuit boards. Whether the analog cards are powered, and the jumper settings for card addresses are integrated on the board. At HollySys, the master controller is directly connected to field I/O modules via PROFIBUS-DP. The FM-type modules feature a non-SMD design, while the SM and nuclear power-specific modules utilize an SMD design. All cards feature a modular design. Module base DIP switch settings for card address. In terms of communication, the WebField JX-300XP system employs a three-layer network structure. The first layer is the information management network—Ethernet (optional for users). This Ethernet network is used for information transmission and management at the plant level; it serves as the information channel for comprehensive plant-wide management. The communication speed is 100 Mbps. The second-layer network is the process control network SCnetII, which connects the system’s control stations, operator stations, engineer stations, communication interface units, etc. It serves as the channel for transmitting real-time process control information. The communication speed is 100 Mbps. The third-layer network is the internal I/O control bus within the control station, known as the SBUS – the internal I/O control bus of the control station. The main control card, data forwarding card, and I/O cards all exchange information via SBUS. The SBUS bus has two layers: the redundant SBUS-S2 bus with a communication rate of 1 Mbps and the SBUS-S1 network with a communication rate of 156 Kbps. The main control card manages the I/O cards distributed in various cages through them. The HOLLiAS MACS system employs a four-layer network structure. The first layer is the information management network, which utilizes an Ethernet network for communication with the system servers via a real-time relational database; the communication speed is 100 Mbps. The second-layer network is a monitoring network that utilizes Ethernet to enable interconnection among engineer stations, operator stations, and system servers. It employs Ethernet communication with a speed of 100 Mbps. The third-layer network is the system network, which enables interconnection between field control stations and system servers; it uses the HSIE network protocol and has no IP addresses. The fourth-layer network is the control network, which facilitates communication between field control stations and process I/O units. The PROFIBUS-DP protocol is used, with a communication rate of 500 Kbps. All process I/O units exchange data with the main controller via a master-slave communication scheme. Any controllers that support the PROFIBUS-DP protocol (such as DCS and PLCs) as well as intelligent instruments can communicate with the MACS as slave devices of the master controller, provided that their respective GSD files are available. In terms of software: The HollySys software system consists of three different sets of software. They have poor compatibility, and there are integration issues between these software components. Holley’s algorithm configuration software is an OEM version of CoDeSYS software developed by Germany’s Smart Software Solution. The upper-level software includes MACS5, which was developed in-house, as well as a Citect OEM version. The controller operating software is QNX from Canada. In terms of configuration, MACS includes device configuration, server algorithm configuration, database configuration, controller algorithm configuration, and graphic configuration. In terms of project implementation, there is a strict sequence for various configurations; after completing each configuration, recompilation is required (except for graphical configurations). This system has a server. When modifying the control algorithm, if any system variables are changed, the database must be recompiled. Furthermore, any changes to the database necessitate a restart of the server. While modifying the control algorithm, after downloading the main controller, the control points of the controller may no longer correspond to those on the server. In such cases, operating from the operator station is very dangerous; operating this device might cause other devices to act, potentially leading to serious personal injuries and equipment accidents. 　CoDeSYS is a development platform for creating control solutions; it uses an IEC-standardized language. It has editor and debugger functions, and is built on top of a development environment for a high-level programming language (Visual C++). 　The CoDeSYS controller algorithm configuration software offers a total of six programming languages. FBD (Function Block Diagram), LD (Ladder Diagram), ST (Structured Text), SFC (Sequential Function Chart), IL (Instruction List), CFC (Continuous Function Chart). FBD and CFC languages are commonly used. Users can use the ST language to write programs with somewhat more complex algorithms; they can also use it to create custom FB modules for use by other programs in the system. The system module library contains a very rich variety of control modules for users to call. However, various programming languages cannot be mixed within the same POU. The entire system operates by having the main program invoke corresponding control algorithm tasks; modules can be customized. The data types used (TIME, DATE, TIME_OF_DAY, DATE_AND_TIME, BOOL, SINT, USINT, BYTE, INT, UINT, WORD, DINT, UDINT, DWORD, REAL, LREAL, Number) are quite complex. The upper-level software MACS5 only supports BOOL and REAL; thus, there are many issues when interfacing it with CoDeSYS. Data from CoDeSYS must undergo type conversion before it can be displayed on the operator station. Some data types simply cannot be uploaded to the operator station (such as arrays). The core component of the programming software developed by Zhejiang University’s SUPCON is the SCKey configuration software. The system features a serverless design; device configuration, database configuration, controller algorithm configuration, and graphical configuration are all integrated into this software. All configurations can be compiled all at once. The SCKey configuration software is a configuration software platform that fully supports all types of control schemes for the system. The software utilizes Object-Oriented Programming (OOP) techniques and Object Linking and Embedding (OLE2) technology. It is developed based on the Chinese version of the Windows operating system and is a 32-bit application software. The entire set of controller algorithms is divided into standard algorithms and custom control algorithms. The standard algorithms include PID single-loop control, cascade double-loop control, feedforward control, manual operator control, etc. The custom control algorithm consists of two parts: graphical configuration (supporting FBD function block diagrams, LD ladder diagrams, SFC sequential function charts, and CFC continuous function charts; these can be used in combination on the same control page). It enables logical control, PID single-loop control, cascade dual-loop control, feedforward control, manual operator control, flow accumulation, data calculations, and more. SCX language configuration: This programming language is a derivative developed based on the C language. Users familiar with C can easily write programs involving relatively complex algorithms using this language. (Programs for communication between the central control DCS and third-party systems are generally written in SCX; these programs utilize a free communication mode, which can be quite cumbersome.) The entire system employs a linear programming approach, and all data types used are user-defined (including Boolean values, as well as 1-byte, 2-byte, 4-byte, and 8-byte data types). When utilizing internal variables, users must have a thorough understanding of both the type of data they’re using and its size; otherwise, their code will fail to compile. In summary, in terms of hardware, HollySys outperforms Zhejiang Supcon. In terms of software configuration, Zhejiang Supcon is superior to HollySys. Regarding system compatibility, Zhejiang Supcon also has the upper hand over HollySys. However, in terms of system openness and functionality, HollySys is better than Zhejiang Supcon