NDKK Central Air Conditioning Control System

1.Summarize

NDKK power plant centralized air-conditioning control system use a distributed control architecture. The central management station of each parameter setting, control strategy changes, running state monitoring, historical data records and via Ethernet communication interface with DCS comply with TCP / IP communication protocol to make a two-way communication to achieve DCS centralized control system for monitoring air-conditioning; operating station measured according to indoor and outdoor air temperature and humidity to calculate the enthalpy of indoor and outdoor air, and thus calculate the enthalpy difference to calculated the air-conditioning load. According to the frequency of outdoor air enthalpy diagram to partition the air conditioning running condition, compare the enthalpy of outdoor air and the district comparative’s critical point to judge conditioned outdoor air condition area belongs to the state, divided air conditioning operating conditions, depending on the different district of operating conditions using different parameters, to achieve air conditioning’s control of multi-annual energy-saving operation conditions.  The station’s control policy is downloaded to the PLC control cabinet, according to the control strategy and parameters ,focus on collecting real-time data of each unit to complete all the control functions with perform the necessary operations.

NDKK centralized air-conditioning control system consists of a central management station, communication networks, controllers (PLC), control cabinets and ancillary equipment, etc. The composition is shown in figure：

2.Functions

Central management operating stations achieve the centralized supervision management and the guidance operation , and realize remote control of the equipment.

Operator station provides a standard user application and friendly open user environment for system expansion, improvement, modification provides a good graphical interface, trend  analysis of the image, easy operation and management to run the air conditioning system to monitor the status of each device on the graphical interface, and displays real-time activity of each device screen, working parameters and fault alarm; operating parameters are graphically displayed on a current or historical moments, including a part of the graphic within the overall plan systems, subsystems and arbitrary system diagram subsystem partial view subsystems or devices, and any other graphical user requirements.  Figure trends may also be made for a variety of different graphic data, the display system parameters change curve within a certain specified period of time in order to run the system for analysis. Conversion between the various graphic freely chosen by a mouse.

Log report printing and parametric curves.

Dispatching operation: the operator can be start / stop system in the management of any device in the central station via the mouse, adjust the valve opening, changing the control setting parameters for each system.  In addition to the operator manual operation, but also for the global management of all automatic scheduling system, such as tuning the system parameter settings and so on.

Fault diagnosis, alarm and fault handling.

Complete database.

Timing control.

3.Configuration

3.1 Basic Configuration

Basic System Configuration for the central management of the operating station, the main cabinet, power boxes.  Among them, the operator station configuration IPC, LED displays, laser printers, optical switches, UPS, network communication interfaces.  Main cabinet configuration of the central unit of the substrate, the substrate expansion unit, I / O stations, communications processors, communication interface module.

3.2 Extended configuration

You can configure the system according to the requirements of users required temperature and humidity sensors, pressure, liquid level transmitter, in situ instrumentation, flow orifice, electric gate, fan inverter cabinets, distribution boxes and electric control actuator and place control cabinet.