Abstract: This paper describes the transformation of boiler instrumentation and control systems using advanced electronic and computer technologies. An advanced DCS system is used as the core of the boiler control system, and variable frequency drive technology is adopted for the boiler's blower, induced draft, and grate motors to protect the motors and save energy. The paper describes the specific implementation schemes, including field instruments, variable frequency drives, DCS control schemes, DCS online commissioning, seamless manual/automatic switching, and manual control cabinets. Keywords: DCS; variable frequency drive; seamless switching; boiler control; three-impulse control. Currently, old-style steam and hot water boilers are still prevalent, relying on outdated instrumentation control, which is inconvenient, untimely, and inefficient. For example, a 20t steam boiler may only produce about 10t of steam. Boilers that have undergone instrumentation and control system transformation using advanced electronic and computer technologies generally employ advanced DCS control. Variable frequency drive technology is used for the boiler's blower, induced draft, and grate motors to protect the motors and save energy. Important boiler operating control parameters are displayed and controlled both on the DCS system and on a dedicated manual control cabinet. The steam drum level is measured and alarmed using three devices: a float level gauge, a differential pressure transmitter, and an electrical contact level gauge. These signals are fed into the DCS (Distributed Control System) and the manual control cabinet, improving the reliability of boiler operation. Adjustments to the boiler blower, induced draft fan, and grate motors can be controlled either through the DCS or on-site. The steam drum level uses a three-impulse control principle, with steam flow as feedforward, feedwater flow as inner loop feedback, and steam drum level as outer loop feedback, achieving control of the steam boiler drum level. Based on actual on-site conditions, the PID control parameters for the steam boiler drum level were tuned, and the control accuracy met design requirements. The adoption of variable frequency drive technology for the boiler blower and induced draft fan motors has yielded considerable economic benefits. 1. Boiler Control Scheme Design The boiler microcomputer control system is an online process control system with functions such as automatic and rapid data acquisition, logic analysis, and precise calculation. It can promptly and conveniently modify adjustment parameters according to the control and calculation requirements of the boiler operation process to achieve the best control effect, thereby improving thermal efficiency, saving energy, and reducing labor intensity. To improve the reliability of system operation, both manual and automatic control modes are adopted. Operators can manually control the system based on experience and the displayed values ​​via a handheld device on the control panel; alternatively, the DCS can automatically perform control calculations according to the set parameters and control model, integrate relevant test parameters and set values ​​through testing, and provide control adjustment quantities, which are then implemented automatically via the handheld device. [b][align=center]For detailed information, please click: Overall Implementation Plan for Boiler Control System[/align][/b]