Small hydropower station long distance control system based on the MODIBUS bus protocol
Technical field
The utility model relates to the technical field of remote monitoring, specifically is a kind of small hydropower station long distance control system based on the MODIBUS bus protocol.
Background technology
Deepen continuously and the continuous development of monitoring technique automatically along with what China power station " unmanned " required, the power station multifunction control system more and more is much accounted of.The automaticity of control system and networked degree direct influence be professional at ordinary times security and the high efficiency that operates to the power station.Traditional manual control mode adopts relay control circuit that relevant device is operated, and its function singleness, extensibility are relatively poor, and circuit structure is complicated, causes the difficulty of maintenance of electric device and renewal bigger.Programmable Logic Controller (PLC) adopts one type of programmable memory, stores embedded program, carries out user oriented instructions such as corresponding logical operation, sequential control, and through numeral or analog output signal control of electrical equipment.System architecture is simplified greatly, and design and debugging work load are less.The user can be according to the actual requirements, and through establishment PLC program, expanding system function or function reconfigured is easy to maintenance at any time, transforms easily, and practicality is very strong.Therefore PLC replaces the conventional means of relay control loop to become inexorable trend as the control core of small hydropower station automation equipment.
The existing automation control system of small hydropower station adopts different PLC equipment to control respectively because function is different.Its number of devices is too much, and hardware cost is too high, and service efficiency is on the low side, and versatility is not strong.
The utility model content
The technical matters that the utility model will solve provides a kind of small hydropower station long distance control system based on the MODIBUS bus protocol simple in structure, lower-cost.
In order to solve the problems of the technologies described above; The utility model provides a kind of small hydropower station long distance control system based on the MODIBUS bus protocol; Comprise: a plurality of field control units, each control module links to each other through the industrial computer that is used for real-time monitoring, controls the service operation state of each field control unit of MODIBUS bus and distant place centralized-control center.
Said field control unit comprises: load module, the processing module that links to each other with this load module, output module that links to each other with this processing module that links to each other with said industrial computer through the MODIBUS bus and the execution module that links to each other with this output module are provided with the field control screen between this output module and the load module.Said a plurality of field control unit is made up of same group of PLC.
Further, the control input end of hydroturbine water intake valve, hydraulic headstock gear gate and the subsidiary engine in said execution module and the small hydropower station links to each other.
The technique scheme of the utility model is compared prior art and had the following advantages: (1) the utility model is integrated in multiple functions such as hydraulic turbine control function, gate opening/closing control function and subsidiary engine control on the same group of PLC equipment; By embedded program; Automatically handle power station a plurality of business demands of control automatically simultaneously; Effectively simplify system architecture, reduction equipment scale and cost, strengthened the versatility and the reliability of PLC equipment.(2) the utility model has designed a kind of network-type operating measurement opertaing device of function synthesizedization to small hydropower station different service demand.This equipment serves as the control core with Programmable Logic Controller (PLC), and through embedded program, the corresponding robotization control of on-the-spot realization in the power station is like the control of hydroturbine water intake valve, the control of hydraulic headstock gear gate, subsidiary engine control etc.Simultaneously; This equipment can also pass through the MODIBUS bus protocol; Carry out communication link with distant place centralized-control center, monitor, control the service operation state of a plurality of power stations field control unit simultaneously, realize networked Long-distance Control by the industrial computer of control center.The switching of " automatically on-the-spot " and " Long-distance Control " operation power can be selected by the change-over switch on the electrical control panel, also can be by the industrial computer Instruction Selection of remote centralized control center.When selecting a kind of control mode, another kind of mode locking, dual mode can switch by unperturbed.The structure of this Combination Control can be controlled the automatic operation of power station water conservancy equipment more reliably.(3) principal feature of the utility model: 1. highly versatile, applicable situation is wide.Can satisfy the multiple water conservancy business demand of small hydropower station.As: the control of hydroturbine water intake valve, the control of hydraulic headstock gear gate, subsidiary engine control etc.PLC equipment also remains with a plurality of subsequent use IO interfaces, and the user can be according to the professional actual conditions in power station, at any time expanding system function or function reconfigured the control function of enhanced system.2. control mode is flexible.The user both can click relevant PLC opertaing device button at the scene, power station; The operation of operation water conservancy equipment; Also can call steering order in remote centralized control center, the equipment operation state of a plurality of power stations of remote monitoring simultaneously field unit through communication network protocol.Be particularly suitable for the occasion of a plurality of power stations uniform dispatching and coordinated management.3. debugging is convenient.If PLC hardware breaks down, be prone to diagnosis, only need to fix a breakdown by module, the spare part of module can have been bought in market, only needs simple the replacing to get final product.If software is when having problems, the user can directly programme, and embedded program is made amendment or expanded, and need not to change hardware device.The programming language of PLC generally adopts trapezoid figure language, and is very similar with relay control circuit, is easier to grasp.The security and the reliability of equipment integral are higher.
Description of drawings
For the content that makes the utility model is more clearly understood, below basis specific embodiment and combine accompanying drawing, the utility model is done further detailed explanation, wherein
Fig. 1 is the structured flowchart based on the small hydropower station long distance control system of MODIBUS bus protocol among the embodiment;
Fig. 2 is the PLC configuration circuit figure of the utility model;
Fig. 3 is the PLC sensor signal load module circuit of the utility model;
Fig. 4 is the oil pump motor control circuit of the utility model.
Embodiment
See Fig. 1; The small hydropower station long distance control system based on the MODIBUS bus protocol of present embodiment; Comprise: a plurality of field control units (being first, second and N field control unit among Fig. 1), each control module links to each other through the industrial computer that is used for real-time monitoring, controls the service operation state of each field control unit of MODIBUS bus and distant place centralized-control center.
Said field control unit comprises: load module, the processing module that links to each other with this load module, output module that links to each other with this processing module that links to each other with said industrial computer through the MODIBUS bus and the execution module that links to each other with this output module are provided with the field control screen between this output module and the load module.Said a plurality of field control unit is made up of same group of PLC equipment.
The gate running status of a plurality of field control units can monitored, control to long-range industrial computer simultaneously through the MODIBUS field bus protocol.
Field control screen can real time monitoring PLC equipment input signal and output state signal, the user clicks screen and goes up button, starts the control corresponding function.
Like Fig. 2, PLC equipment group is made up of communication module, CPU module, sensor signal load module, control signal load module and control signal output module.Communication module is used for field control unit and long-range industrial computer are set up communication link, satisfies the Long-distance Control demand of industrial computer to PLC.The CPU module is the control maincenter of PLC, receives and storaging user data and order, presses computing of embedded program actuating logic or control task, and the result is sent to corresponding output device.16 gate valve sensor signal and function control signal are admitted to load module, after the CPU resume module, export the function executing unit to, drive the operation of relevant device.
The PLC sensor signal load module circuit of the utility model is as shown in Figure 3.16 sensing data is obtained by absolute type shaft-position encoder FB900C, and inputs to digital quantity input module SM321.The CPU module is according to the sensor measurement data, and the electric motor state of control and executive module like parameters such as motor speed, directions, and is brought in constant renewal in sensing data in real time.
PLC control signal input/output module circuit adopts SM321 as input equipment, an external switch, a plurality of control knob, subsidiary engine control load module and subsequent use load module.Switch is used for selecting the corresponding work mode from " scene is controlled automatically " and " Long-distance Control " button, when selecting a kind of mode, and other type automatic blocking.Again gate valve is operated subsequently, pushed corresponding gate valve rising button, gate valve decline button or gate valve stop button, send command signal.When system produces fault, can be by fault SR reset system state.The subsidiary engine control function is started by corresponding subsidiary engine control knob.Whether the energising that work oil pump and emergency bearing oil pump detect relay coil by oil pressure determines the unlatching of corresponding function and stops.The subsequent use pin of load module can insert other electrical equipments according to user's request, with the input function of expanding system.
Sensor input signal and control input signals export digital quantity output module SM322 to after the embedded routine processes of PLC.The output signal both can show corresponding gate valve rising, descend, stop and the oil pump malfunction, again can be to surplus valve, gate valve rising solenoid valve, gate valve decline solenoid valve and the energising of motor start-up contactor coil, to start corresponding systemic-function.When serious problems appearred in system, the warning reminding user noted automatically, to take appropriate measures.Subsidiary engine output signal is then in order to functions such as the draining of control seepage, fan operation, air compressions.When PLC detects the reduction of oil pump operating oil pressure,, start the working oil pumping function of input equipment automatically to the energising of work oil pump relay coil; Cross when low when PLC detects the oil pump operating oil pressure,, open the emergency bearing oil pump function of input equipment the energising of emergency bearing oil pump relay coil; When PLC detects the oil pump operating oil pressure when too high, open draining valve, keep the oil pressure balance of motor; If the operating oil pressure of oil pump just often, then need not to work oil pump and the energising of emergency bearing oil pump relay coil the above-mentioned functions of stopping using automatically.The expansion output function of subsequent use output interface feasible system.
The oil pump motor control circuit is as shown in Figure 4.Three-phase supply power supply, automatic air-break switch break-make power supply are adopted in the Oil pump electrical machinery loop.The running of Oil pump electrical machinery is opened or stopped to the motor start-up probe of contactor according to the energising of its contactor coil whether.The electrothermal relay thermal element links to each other with Oil pump electrical machinery, makes motor under high-temperature work environment, automatic shutdown protection.Control signals such as the oil pump switching of oil pump motor, motor rotation direction, motor speed adjusting provide by the PLC output module.