NOVELTY - The system comprises a main control sub-system, a programmable logic controller (PLC) control sub-system and a control sub-system. The PLC control sub-system and the main control sub-system are connected with the control sub-system. The control sub-system comprises a material collecting unit which is connected to a sand preparing unit, a marsh gas production unit, a storage unit, a mud-water separating unit and a marsh gas power generation unit. The storage unit is connected with the main control sub-system.    USE - Used as a marsh gas fermentation control system.    ADVANTAGE - The system improves marsh gas fermentation with stability and reliability in a real-time, is convenient for information management, reduces the manufacturing cost, improves working efficiency and prevents accident.    DETAILED DESCRIPTION - The marsh gas generator control system comprises a main control sub-system, a programmable logic controller (PLC) control sub-system and a control sub-system. The PLC control sub-system and the main control sub-system are connected with the control sub-system. The control sub-system comprises a material collecting unit which is connected a sand preparing unit, a marsh gas production unit, a storage unit, a mud-water separating unit and a marsh gas power generation unit. The sand preparing unit, the material collecting unit, the marsh gas production unit, the storage unit and the mud-water separating unit are connected with the marsh gas power generation unit. The storage unit is connected with the main control sub-system, which is connected with the PLC control sub-system automatically controlled by the control sub-system. The material collecting unit comprises a first liquid level detecting device, a stirrer, a crusher, a conveying pump and a submersible sewage pump. The first liquid level detecting device detects the liquid level in the collecting tank. The PLC control subsystem is provided with the first liquid level detecting device and the stirrer, controls the crusher to crush the material, and controls the delivery pump to pump the material and sand removing operation. The sand preparing unit comprises a spiral conveyor, a second liquid level detecting device and a diving stirrer. The second liquid level detecting device detects the liquid level in the preparing tank. The PLC control sub-system is connected with the spiral conveyor to place sand in the sand tank. The marsh gas production unit comprises a marsh gas fermentation tank, a temperature adjusting unit, a temperature sensor and a transducer. The PLC control sub-system comprises a first analog to digital converter, a subtractor, a controller, a second analog to digital converter, a transducer and a temperature sensor. The analog to digital converter is connected with the subtractor and the controller. The temperature sensor detects the temperature in the marsh gas fermentation tank to produce an analog temperature signal. The transmitter transmits the analog temperature signal as standard direct current (DC) signal to a DC voltage signal. The first analog to digital converter converts the direct current signal or DC voltage signal into a digital signal. The subtractor subtracts difference between a set temperature and temperature calculated by the first analog to digital converter. The controller controls proportional integral-derivative (PID) control algorithm to calculate difference value obtained by the second analog to digital converter and controls the temperature of the marsh gas fermentation tank. The temperature adjusting unit is the electric adjusting valve in the hot water circulation temperature closed loop control system to control the flow rate of the hot water in the heater by adjusting the opening degree of the electric adjusting valve. The PLC control subsystem further comprises a temperature display unit which displays temperature of the marsh gas fermentation tank. The main control sub-system further comprises a warning unit. The mud-water separating unit comprises a mud-water separating mechanism and a third liquid level detecting device, which is used for detecting the liquid level height in the liquid buffer tank. The marsh gas power generation unit comprises a generating unit and a biogas regulator. The main control sub-system monitors the operation condition of the generating unit by the PLC control sub-system. The PLC control sub-system controls the gas regulator to regulate marsh gas flow rate and pressure parameter. The main control sub-system comprises a timing unit, which sets operation time of the material collecting unit, the removing sand preparing unit, the marsh gas production unit, the storage unit, the mud water separating unit and the marsh gas power generation unit.