Diesel generator automatic control system can be divided into the following four categories:

     (1) The first category is the relay control logic control with semiconductor devices, operating a simple and effective.  The disadvantage is that many components, circuit complexity, bulky and poor reliability. For added functionality, you need to modify the control circuitry.

     (2) second control mode using the program controller replaces the first method of a semiconductor device logic circuit, so that the hardware standardization, the use of professional language makes programming easy; software change control circuit, very convenient.  As a result of reducing the number of large scale integrated circuits and software components that have self-test function and other reasons, to improve reliability.

     (3) The third category is the use of micro-computer control mode to replace the manual operation and management, open into process control controller, microcomputer standardized analog controller combination. The start-stop, side by side, splitting and load distribution as an independent unit with the computer connected with the software implementation of the whole process automatic control, the operation easier.  However, measures need to be taken back to avoid computer failure caused by out of control.

     (4) The fourth category is microcomputer control mode or programmable logic controller (PLC) to achieve the diesel generator power plant automation.  Hardware components easier, but must be considered a reliable back-up measures.  It can not only achieve control, but also for data processing and scientific calculation, and the operation speed and precision fully meet the control, the advantage is the three kinds of control program stored in the memory, the wiring is limited to detecting element is connected to the actuator , so that the hardware and wiring simplification, so its reliability is high and wide adaptability, easy to debug and maintain. We flew Swiss electronic generator controller is the fourth class of control, it is also the diesel generator automatic control system development.

    Development of automated generators and production began in the 1960s, the unit uses the first and second control mode supporting the production of more varieties, to be applied on the field of communications systems and shipbuilding industry.  With the development of computer technology, especially in microprocessor-based programmable logic controller (PLC) applications and development, so that the fourth category automated generators rapid emergence.  Programmable logic controller (PLC) is an integrated computer, control, communications and CRT display technology developed can be combined as needed to accommodate the needs of different levels and scales of automatic control devices.  In particular, it can adapt to the microcomputer industry than the harsh environment, so, PLC has been widely used in various automation and control.