JPH09160634A - State monitoring system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a monitor system which eliminates complicated wiring between a sensor and a power generator board. SOLUTION: The output signals of a pressure sensor 23, a main O2 sensor, an exhaust temperature sensor 27, and a subordinate O2 sensor 29 are sent to a terminal device 31 installed in a machine room 1. A central management device 37 in an electronic chamber 5 when requiring the values of the respective sensors sends a message for polling to the terminal device 31. The terminal device 31 sends a message carrying the values of the respective sensors to the central management device 38, which processes the received information and outputs its result to the power generator board 35, so that the values of the respective sensors are displayed at the display part of the power generator board 35.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a status monitoring system for monitoring the status of various sensors in a cogeneration system.

[0002]

2. Description of the Related Art Generally, a cogeneration system uses a gas engine or the like to simultaneously generate electric power and heat. The gas engine and the like are placed in the machine room, and the electric room is equipped with a generator panel. Signals from various sensors attached to the gas engine or the like are sent to the generator panel via a signal line for each sensor.

[0003]

As described above, in the conventional cogeneration system, it is necessary to lay a signal cable for each sensor between various sensors and the generator panel, which requires time for wiring work and the like. When the wiring distance was long, noise or the like was generated and wiring was erroneous. The present invention has been made in view of such a problem, and an object thereof is to provide a condition monitoring system without complicated wiring between a sensor and a generator panel.

[0004]

To achieve the above object, the present invention provides a plurality of sensors installed in a machine room of a cogeneration system, and a terminal device to which output signals of the plurality of sensors are sent. A condition monitor characterized in that the values of the plurality of sensors are sent to the central management device by communicating between the central management device installed in the electric room and the terminal device and the central management device. System.

[0005]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a layout diagram of a cogeneration system according to an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a machine room, in which a gas engine / generator and auxiliary equipment 3 such as a fan and a pump are installed. Reference numeral 5 is an electric room, and a generator board 35, an auxiliary board, a DC power board (not shown), etc. are installed in the electric room 5.

FIG. 2 is a schematic configuration diagram of the condition monitoring system. In a cogeneration system using a gas engine, a gas engine 4 is installed in the machine room 1.
The gas engine 4 has an intake manifold 9, an exhaust manifold 13, an intake valve 11, an exhaust valve 15 and the like. Mixer 7, throttle valve 19, actuator 2 on the intake side
1, a pressure sensor 23 and the like are provided. A three-way catalyst 17, a main O2 sensor 25, an exhaust temperature sensor 27, a sub O2 sensor 29, etc. are provided on the exhaust side.

Air and city gas are mixed in the mixer 7, and the intake valve 11 is adjusted while the amount thereof is adjusted by the throttle valve 19.
Sent to the gas engine 4 via the
The combustion process is repeated within. Exhaust gas is exhaust valve 15
And is sent to the exhaust manifold 13 via the three-way catalyst 17 to remove NOx and the like.

The actuator 21 regulates the amount of city gas delivered to the intake manifold 9. The pressure sensor 23 detects the pressure of the intake manifold 23. The main O2 sensor 25 detects the amount of oxygen in the exhaust manifold 13. The exhaust temperature sensor 27 detects the temperature of exhaust gas. The sub O2 sensor 29 detects the oxygen amount of the exhaust gas that has passed through the three-way catalyst 17.

The pressure sensor 23, the main O 2 sensor 25,
Output signals of the exhaust temperature sensor 27 and the sub O 2 sensor 29 are sent to the terminal device 31. Further, the actuator 21 is driven by the terminal device 31. The terminal device 31 is a communication device having an I / O port for capturing output signals from various sensors and a signal conversion unit.

A generator panel 35 is installed in the electric room 5, a central control device 37 is installed in the generator panel 35, and the terminal device 31 and the central control device 37 are connected by a transmission line 33 such as a pair of cables. To be done. Note that not only one terminal device 31 but also a plurality of terminal devices may be provided, and output signals of different sensors may be sent to each terminal device.

FIG. 3 is a schematic configuration diagram of the terminal device 31. The terminal device 31 has an interface (I / F) 51,
It has a CPU 53, a DIP switch 55, a modem 57, a communication mode changeover switch 58, and the like. The interface 51 controls the interface between the CPU 53 and each sensor. Output signals from various sensors such as the pressure sensor 23, the main O2 sensor 25, the exhaust gas temperature sensor 27, and the sub O2 sensor 29 are sent to the terminal device 31. The CPU 53 performs various calculations, protocol control, message assembly, and the like. The DIP switch 55 is operated by the operator to operate the terminal device 31.
Set the address of The modem 57 modulates and demodulates the signal. When there are a plurality of terminal devices, address settings are performed so that they do not overlap. The communication mode switch 58 switches between the polling mode and the calling mode.

FIG. 4 is a schematic block diagram of the central management unit 37. The central management unit 37 includes a modem 61, a CPU 63, an interface (I / F) 65, a DIP switch 6
6. It has a communication mode changeover switch 67 and the like. Modem 6
1 performs modulation / demodulation of a signal. The CPU 63 performs various calculations, protocol control, message assembly, and the like. The interface 65 controls the interface with the internal circuit of the generator panel 35. The switch 55 gives an address. The communication mode switch 67 includes a polling mode, a calling mode,
Switch the fixed mode. The fixed mode is a mode in which, when a plurality of terminal devices are installed, polling communication is performed with only one certain terminal device, and the setting is performed by the DIP switch 66.

FIG. 5 shows the central management unit 37 to the terminal unit 3.
3 is a format diagram of a telegram 71 sent to No. 1. Message 7
1 includes a start bit (ST) 73, an address 75, request information 77, and a stop bit (SP) 79. The start bit 73 indicates the start of the telegram 71, and the address 7
5 is the address value of the terminal device that is the communication partner. The request information 77 is, for example, information about which sensor value is desired. The stop bit 79 indicates the end of the telegram 71.

In the terminal device 31, these "0",
The digital information of “1” is modulated by the modem 57 (frequency shift method) and sent to the transmission line 33. The modulation frequency sent from the central management device 37 to the terminal device 31 and the modulation frequency sent from the terminal device 31 to the central management device 37 are changed. This prevents erroneous communication. When the same frequency is used, a code is provided in the message to identify whether it is the message from the central management device 37 or the message from the terminal device 31.

FIG. 6 shows the terminal device 31 to the central management device 3.
7 is a format diagram of a message 81 sent to the No. Message 8
1 is a start bit (ST) 83, address 85, request information 87, status information 89, stop bit (SP) 91.
Consists of The start bit 83 indicates the beginning of the electronic message 81, the address 85 is the address value of the terminal device itself which sends the electronic message 81, and the request information 87 carries the request information 77 sent from the central management unit 37 as it is. The state information 89 is an output signal of each sensor. The stop bit 91 indicates the end of the electronic message 81.

Next, the general operation of this embodiment will be described. For example, output signals of various sensors when the gas engine 4 is in operation are sent to the terminal device 31 or another terminal device (not shown) at any time. The central management device 37 polls each terminal device. That is, the message 71 shown in FIG. 5 is sent to each terminal device. For example,
The address of the terminal device 31 is written in the address 75, information about which sensor value is desired is written in the request information 77, and the information is sent to the terminal device 31. Further, for another terminal device (not shown), the address value of the terminal device is written in the address 77, and a message 71 is sent in the same manner.

When the message 71 is sent, the terminal device 31 writes the output signal of the sensor required in accordance with the request information 77 into the status information 89 and sends it back to the central management unit 37.

The central control device 37 polls each terminal device, and the output signal of each sensor is written in the status information 89 and sent from each terminal device, so that the value of each sensor can be easily known. it can. Then, the values of the respective sensors are sent from the central management device 37 to the display section (not shown) of the power generator panel 35 and displayed on the display section of the generator panel 35.

The communication between the terminal device 31 and the central management device 37 is, for example, a half-duplex communication system as a communication system,
The start-stop synchronization method is used as the synchronization method, and the inverted double-transmission matching is used as the detection method. Further, in response to the call from the central management device 37, if the electronic message from the terminal device 31 cannot be received within the predetermined time, the central management device 37 sends the electronic message 71 again. If a message from the terminal device cannot be received even after retransmitting the message a predetermined number of times, a communication error occurs.

Further, the terminal device 31 and the generator panel 35 may be communicated by a wireless system. In addition, the terminal device 31 compares the set value set for each sensor with the output place, determines an abnormal state, and when it is determined to be abnormal, the central management device 37 outputs the output value, the determination result, and other information. Data may be sent.

As described above, according to this embodiment, the following effects can be obtained. Terminal device 31 and central management device 3
Since a single transmission path 33 is used to connect the wirings 7 and 7, a large number of wirings as in the prior art are not required. When the number of sensors and the like is newly increased, it is sufficient to extend the signal line from the sensor to the terminal device, which is excellent in expandability. Generator board 3
Since the communication system is used between the sensor 5 and the sensor, the influence of noise or the like can be reduced. In addition, although the co-generation system that uses the gas engine has been described in the above-described embodiment, the present invention can also be applied to a co-generation system that uses a gas turbine or the like.

[0022]

As described in detail above, according to the present invention, it is possible to provide a condition monitoring system without complicated wiring between the sensor and the generator panel.

[Brief description of the drawings]

[Fig. 1] Layout of the cogeneration system

FIG. 2 is a schematic configuration diagram of a condition monitoring system.

FIG. 3 is a schematic configuration diagram of the terminal device 31.

FIG. 4 is a schematic configuration diagram of a central management device 37.

FIG. 5 is a format diagram of a telegram 71.

FIG. 6 is a format diagram of a message 81.

[Explanation of symbols] 23 ......... Pressure sensor 25 ... Main O2 sensor 27 ... Exhaust temperature sensor 29 ... Sub O2 sensor 31 ... Terminal device 33 ... Transmission line 35 ... Generator Board 37 ... Central control device

Claims (5)

[Claims] 1. A plurality of sensors installed in a machine room of a cogeneration system, a terminal device to which output signals of the plurality of sensors are sent, a central management device installed in an electric room, the terminal device and the terminal device. A condition monitoring system, wherein the values of the plurality of sensors are sent to the central management device by communicating with the central management device. 2. The condition monitoring system according to claim 1, wherein there are a plurality of the terminal devices, and output signals of different sensors are sent to the respective terminal devices. 3. The condition monitoring system according to claim 2, wherein the central management device fetches the values of the plurality of sensors by polling the plurality of terminal devices. 4. The terminal device compares a set value set for each sensor with an output value of each sensor, determines an abnormal state, and outputs an output to the central management device when it is determined to be abnormal. The condition monitoring system according to claim 2, wherein the value, the determination result, and other data are sent. 5. The condition monitoring system according to claim 1, wherein the terminal device and the central management device are communicated by wire or wirelessly.