Generator shaft voltage and shaft current on-line monitoring device

Abstract

The invention particularly relates to a generator shaft voltage and shaft current on-line monitoring device, which comprises a data acquisition and processing unit, a control unit and an upper computer, and is characterized in that the data acquisition and processing unit is in communication connection with the control unit, and the upper computer is in communication connection with the control unit; the data acquisition and processing unit is used for acquiring generator shaft voltage signals and generator shaft current signals in real time and sending the signals to the control unit in real time; the control unit is used for receiving the generator shaft voltage signal and the generator shaft current signal sent by the data acquisition and processing unit in real time, generating generator shaft voltage real-time monitoring data and generator shaft current real-time monitoring data and sending the data to the upper computer in real time; and the upper computer is provided with upper computer monitoring software and is used for receiving the generator shaft voltage real-time monitoring data and the generator shaft current real-time monitoring data sent by the control unit in real time. According to the invention, high-precision and high-anti-interference real-time monitoring of the shaft voltage and the shaft current of the generator is realized.

Description

Technical Field

[0001] The invention relates to the technical field of generator shaft voltage and shaft current monitoring, and in particular to an online monitoring device for generator shaft voltage and shaft current. Background Art

[0002] During the operation of the nuclear power unit's steam turbine generator, an induced voltage, called shaft voltage, is generated on the rotor shaft due to reasons such as magnetic circuit asymmetry, static electricity generated by friction between steam and blades, and pulsating voltage and residual magnetism generated by the static excitation system.

[0003] When the nuclear power unit is operating normally, the shaft voltage does not exceed the damage value of the bearing oil film, and the shaft current is very small. If the shaft voltage exceeds the breakdown voltage of the bearing oil film, a large shaft current will be formed on the bearing. The shaft current discharges between the rotor and the bearing, which will cause damage to the bearings, bushings, gears and other bearing components. In severe cases, it will also cause shutdown accidents and cause significant losses to the motor. Due to the harm of shaft voltage and shaft current to the generator, it is necessary to implement online monitoring of the motor shaft current and shaft voltage of the generator. Summary of the invention

[0004] Based on this, it is necessary to provide an online monitoring device for the shaft voltage and shaft current of a generator to address the above problems, so as to realize real-time monitoring of the shaft voltage and shaft current of the generator with high precision and high anti-interference performance.

[0005] In order to solve the above problems, the present invention provides the following technical solutions:

[0006] A generator shaft voltage and shaft current online monitoring device comprises a data acquisition processing unit, a control unit and a host computer, wherein the data acquisition processing unit is communicatively connected with the control unit, and the host computer is communicatively connected with the control unit;

[0007] The data acquisition processing unit is used to collect the generator shaft voltage signal and the generator shaft current signal in real time and send them to the control unit in real time;

[0008] The control unit is used to receive the generator shaft voltage signal and the generator shaft current signal sent by the data acquisition and processing unit in real time; respectively calculate the generator shaft voltage signal and the generator shaft current signal sent by the data acquisition and processing unit in real time, generate the generator shaft voltage real-time monitoring data and the generator shaft current real-time monitoring data, and send them to the host computer in real time;

[0009] The host computer is installed with the host computer monitoring software, which is used to receive the real-time monitoring data of the generator shaft voltage and the real-time monitoring data of the generator shaft current sent by the control unit in real time.

[0010] As one of the feasible ways, the control unit is connected to the host computer through a communication unit, and the control unit sends the real-time monitoring data of the generator shaft voltage and the real-time monitoring data of the generator shaft current to the host computer in real time through the communication unit.

[0011] As one of the feasible ways, the communication unit is provided with a USB interface, an RS485 serial port and an Ethernet communication interface.

[0012] As one of the feasible ways, the data acquisition and processing unit adopts a photoelectric coupling device.

[0013] As one of the achievable methods, a voltage collector and a current transformer are provided on the data acquisition processing unit;

[0014] The voltage collector circuit is connected between the main shaft on the generator exciter side and the main shaft grounding wire on the generator turbine side, and is used to collect the generator shaft voltage signal in real time;

[0015] The current transformer circuit is connected to the generator shaft grounding wire and is used to collect the generator shaft current signal in real time.

[0016] As one of the feasible ways, the current transformer is a through-type current transformer with a current transformation ratio of 10A / 100mA; the voltage collection range of the voltage collector 1 is 0V-100V.

[0017] As one of the achievable ways, the generator shaft voltage and shaft current online monitoring device further includes an alarm unit, which is communicatively connected with the control unit;

[0018] The control unit is also used to generate a generator shaft voltage alarm signal and a generator shaft current alarm signal; and send the generated generator shaft voltage alarm signal and the generator shaft current alarm signal to the alarm unit;

[0019] The alarm unit is used to receive the generator shaft voltage alarm signal and the generator shaft current alarm signal sent by the control unit and to make corresponding alarms respectively.

[0020] As one of the achievable methods, the control unit generates a generator shaft voltage alarm signal and a generator shaft current alarm signal, including the following steps:

[0021] The control unit compares the real-time monitoring data of the generator shaft voltage and the real-time monitoring data of the generator shaft current with the alarm thresholds set by the control unit;

[0022] If the real-time monitoring data of the generator shaft voltage exceeds the set alarm threshold, a generator shaft voltage alarm signal is generated;

[0023] If the real-time monitoring data of the generator shaft current exceeds its set alarm threshold, a generator shaft current alarm signal is generated.

[0024] As one of the feasible ways, the alarm threshold of the alarm unit is set by a host computer.

[0025] As one possible implementation, the alarm unit includes a relay and an indicator light, and the relay and the indicator light are circuit-connected;

[0026] The generator shaft current alarm signal includes a generator shaft current over-high alarm signal, and the generator shaft voltage alarm signal includes a generator shaft voltage over-high alarm signal and a generator shaft voltage under-low alarm signal;

[0027] After the alarm unit receives the generator shaft current over-high alarm signal, the generator shaft voltage over-high alarm signal or the generator shaft voltage under-low alarm signal sent by the control unit, it controls the relay contacts to operate and the indicator light to light up.

[0028] As one possible implementation, the generator shaft voltage and shaft current online monitoring device further includes a display unit; the display unit is communicatively connected with the control unit;

[0029] The control unit is also used to send the generator shaft voltage real-time monitoring data and the generator shaft current real-time monitoring data to the display unit in real time;

[0030] The display unit is used to receive the real-time monitoring data of the generator shaft voltage and the real-time monitoring data of the generator shaft current sent by the control unit in real time; and convert the real-time monitoring data of the generator shaft voltage and the real-time monitoring data of the generator shaft current into spectrum characteristic data and then display them.

[0031] As one possible implementation, the display unit is a touch screen.

[0032] As one of the achievable methods, the generator shaft voltage and shaft current online monitoring device further includes an analog input and output unit; the analog input and output unit is provided with an analog input interface and an analog output interface, and the analog input interface and the analog output interface are respectively connected to the control unit for communication;

[0033] The analog input and output unit is used to connect the external input analog signal to the control unit through the analog input interface; the real-time monitoring data of the generator shaft voltage and the real-time monitoring data of the generator shaft current generated by the control unit are output as analog output signals through the analog output interface to the external system for display;

[0034] The control unit is also used to send the external input analog signal to the display unit; the display unit is also used to receive and display the external input analog signal sent by the control unit.

[0035] As one of the achievable methods, the analog input and output unit is provided with 5-way (4-20) mA analog input interface and 8-way (4-20) mA analog output interface.

[0036] As one of the achievable methods, the generator shaft voltage and shaft current online monitoring device further includes a storage unit; the storage unit is communicatively connected with the control unit;

[0037] The control unit is also used to send the generator shaft voltage real-time monitoring data and the generator shaft current real-time monitoring data to the storage unit;

[0038] The storage unit is used to receive and store the real-time monitoring data of the generator shaft voltage and the real-time monitoring data of the generator shaft current sent by the control unit to form the historical monitoring data of the generator shaft voltage and the historical monitoring data of the generator shaft current.

[0039] Beneficial technical effects of the present invention:

[0040] The online monitoring device for generator shaft voltage and shaft current of the present invention realizes high-precision, high-anti-interference real-time monitoring of the shaft voltage and shaft current of a (0-1500) Hz generator; the control unit generates an alarm signal when the generator shaft voltage or the generator shaft current exceeds its set alarm threshold, and after receiving the alarm signal, the alarm unit controls the relay contacts to operate and the indicator light to alarm; the control unit transmits the real-time monitoring data of the generator shaft voltage and the real-time monitoring data of the generator shaft current to the host computer in real time, thereby realizing the real-time acquisition of the real-time monitoring data of the generator shaft voltage and the real-time monitoring data of the generator shaft current, and facilitating timely discovery of the turbine generator shaft voltage fault and the generator shaft current fault; the storage unit stores the historical monitoring data of the generator shaft voltage and the historical monitoring data of the generator shaft current for a long time, providing a favorable diagnostic basis for the maintenance and overhaul of the generator, thereby effectively reducing the maintenance cost of the generator. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a structural schematic diagram of an embodiment of a generator shaft voltage and shaft current online monitoring device of the present invention;

[0042] Figure 2 Schematic diagram of generator shaft voltage and shaft current. DETAILED DESCRIPTION

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used in the specification of the application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0044] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0045] The technical solution of the present invention is clearly and completely described below in conjunction with the accompanying drawings and specific embodiments.

[0046] See also Figure 1 , This embodiment provides an online monitoring device for generator shaft voltage and shaft current, including a data acquisition processing unit, a control unit and a host computer, the data acquisition processing unit is communicatively connected to the control unit, and the host computer is communicatively connected to the control unit;

[0047] The data acquisition processing unit is used to collect the generator shaft voltage signal and the generator shaft current signal in real time and send them to the control unit in real time;

[0048] The control unit is used to receive the generator shaft voltage signal and the generator shaft current signal sent by the data acquisition and processing unit in real time; respectively calculate the generator shaft voltage signal and the generator shaft current signal sent by the data acquisition and processing unit in real time, generate the generator shaft voltage real-time monitoring data and the generator shaft current real-time monitoring data, and send them to the host computer in real time;

[0049] The host computer is installed with the host computer monitoring software, which is used to receive the real-time monitoring data of the generator shaft voltage and the real-time monitoring data of the generator shaft current sent by the control unit in real time.

[0050] In the generator shaft voltage and shaft current online monitoring device of this embodiment, the data acquisition processing unit collects the generator shaft voltage signal and the generator shaft current signal in real time, and the control unit generates the generator shaft voltage real-time monitoring data and the generator shaft current real-time monitoring data and transmits them to the host computer in real time, so as to timely detect the steam turbine generator shaft voltage fault and the generator shaft current fault.

[0051] See also Figure 2The generator converts the magnetic field provided by the exciter into electrical energy output to achieve power generation; the generator shaft voltage signal is the voltage signal of the main shaft on the generator exciter side to the grounding position of the main shaft on the generator turbine side, and the generator shaft current signal is the current signal on the grounding wire of the generator main shaft.

[0052] In this embodiment, as one of the feasible ways, the control unit is connected to the host computer through a communication unit, and the control unit sends the real-time monitoring data of the generator shaft voltage and the real-time monitoring data of the generator shaft current to the host computer in real time through the communication unit.

[0053] In this embodiment, as one of the implementable ways, the communication unit is provided with a USB interface, an RS485 serial port and an Ethernet communication interface.

[0054] In this embodiment, as one of the feasible methods, the data acquisition and processing unit adopts a photoelectric coupling device, which has high precision and high anti-interference ability, and realizes real-time acquisition of the generator shaft voltage signal and the generator shaft current signal with high precision and high anti-interference ability.

[0055] In this embodiment, as one of the achievable methods, a voltage collector and a current transformer are provided on the data acquisition processing unit;

[0056] The voltage collector circuit is connected between the main shaft on the generator exciter side and the main shaft grounding wire on the generator turbine side, and is used to collect the generator shaft voltage signal in real time;

[0057] The current transformer circuit is connected to the generator shaft grounding wire and is used to collect the generator shaft current signal in real time.

[0058] In this embodiment, as one of the achievable ways, the current transformer is a through-type current transformer with a current transformation ratio of 10A / 100mA; the voltage collection range of the voltage collector 1 is 0V-100V.

[0059] In this embodiment, as one of the achievable ways, the generator shaft voltage and shaft current online monitoring device further includes an alarm unit, and the alarm unit is communicatively connected with the control unit;

[0060] The control unit is also used to generate a generator shaft voltage alarm signal and a generator shaft current alarm signal; and send the generated generator shaft voltage alarm signal and the generator shaft current alarm signal to the alarm unit;

[0061] The alarm unit is used to receive the generator shaft voltage alarm signal and the generator shaft current alarm signal sent by the control unit and to make corresponding alarms respectively.

[0062] In this embodiment, as one of the achievable methods, the control unit generates a generator shaft voltage alarm signal and a generator shaft current alarm signal, including the following steps:

[0063] The control unit compares the real-time monitoring data of the generator shaft voltage and the real-time monitoring data of the generator shaft current with the alarm thresholds set by the control unit;

[0064] If the real-time monitoring data of the generator shaft voltage exceeds the set alarm threshold, a generator shaft voltage alarm signal is generated;

[0065] If the real-time monitoring data of the generator shaft current exceeds its set alarm threshold, a generator shaft current alarm signal is generated.

[0066] In this embodiment, as one of the achievable methods, the alarm threshold of the alarm unit is set by a host computer.

[0067] In this embodiment, as one of the achievable ways, the alarm unit includes a relay and an indicator light, and the relay and the indicator light are connected by a circuit;

[0068] The generator shaft current alarm signal includes a generator shaft current over-high alarm signal, and the generator shaft voltage alarm signal includes a generator shaft voltage over-high alarm signal and a generator shaft voltage under-low alarm signal;

[0069] After the alarm unit receives the generator shaft current over-high alarm signal, the generator shaft voltage over-high alarm signal or the generator shaft voltage under-low alarm signal sent by the control unit, it controls the relay contacts to operate and the indicator light to light up.

[0070] In this embodiment, as one of the achievable methods, the generator shaft voltage and shaft current online monitoring device further includes a display unit; the display unit is communicatively connected with the control unit;

[0071] The control unit is also used to send the generator shaft voltage real-time monitoring data and the generator shaft current real-time monitoring data to the display unit in real time;

[0072] The display unit is used to receive the real-time monitoring data of the generator shaft voltage and the real-time monitoring data of the generator shaft current sent by the control unit in real time; and convert the real-time monitoring data of the generator shaft voltage and the real-time monitoring data of the generator shaft current into spectrum characteristic data and then display them.

[0073] In this embodiment, as one of the implementable manners, the display unit is a touch screen.

[0074] In this embodiment, as one of the achievable methods, the generator shaft voltage and shaft current online monitoring device further includes an analog input and output unit; the analog input and output unit is provided with an analog input interface and an analog output interface, and the analog input interface and the analog output interface are respectively connected to the control unit for communication;

[0075] The analog input and output unit is used to connect the external input analog signal to the control unit through the analog input interface; the real-time monitoring data of the generator shaft voltage and the real-time monitoring data of the generator shaft current generated by the control unit are output as analog output signals through the analog output interface to the external system for display;

[0076] The control unit is also used to send the external input analog signal to the display unit; the display unit is also used to receive and display the external input analog signal sent by the control unit.

[0077] In this embodiment, as one of the achievable methods, the analog input and output unit is provided with 5-way (4-20) mA analog input interface and 8-way (4-20) mA analog output interface.

[0078] In this embodiment, as one of the achievable methods, the generator shaft voltage and shaft current online monitoring device further includes a storage unit; the storage unit is communicatively connected with the control unit;

[0079] The control unit is also used to send the generator shaft voltage real-time monitoring data and the generator shaft current real-time monitoring data to the storage unit;

[0080] The storage unit is used to receive and store the real-time monitoring data of the generator shaft voltage and the real-time monitoring data of the generator shaft current sent by the control unit to form the historical monitoring data of the generator shaft voltage and the historical monitoring data of the generator shaft current.

[0081] The generator shaft voltage historical monitoring data and the generator shaft current historical monitoring data can be stored through the storage unit, which is convenient for viewing and analyzing the generator shaft voltage historical monitoring data and the generator shaft current historical monitoring data through the host computer at a later time.

[0082] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A generator shaft voltage and shaft current online monitoring device, characterized in that: It includes a data acquisition and processing unit, a control unit and a host computer, wherein the data acquisition and processing unit is connected to the control unit for communication, and the host computer is connected to the control unit for communication; The data acquisition processing unit is used to collect the generator shaft voltage signal and the generator shaft current signal in real time and send them to the control unit in real time; The control unit is used to receive in real time the generator shaft voltage signal and the generator shaft current signal sent in real time by the data acquisition and processing unit; The generator shaft voltage signal and the generator shaft current signal sent by the data acquisition and processing unit in real time are respectively calculated in real time, and the generator shaft voltage real-time monitoring data and the generator shaft current real-time monitoring data are generated and sent to the host computer in real time; The host computer is installed with the host computer monitoring software, which is used to receive the real-time monitoring data of the generator shaft voltage and the real-time monitoring data of the generator shaft current sent by the control unit in real time.

2. The generator shaft voltage and shaft current online monitoring device according to claim 1, characterized in that: The data acquisition and processing unit adopts photoelectric coupling devices.

3. The generator shaft voltage and shaft current online monitoring device according to claim 2, characterized in that: The data acquisition and processing unit is provided with a voltage collector and a current transformer; The voltage collector circuit is connected between the main shaft on the generator exciter side and the main shaft grounding wire on the generator turbine side, and is used to collect the generator shaft voltage signal in real time; The current transformer circuit is connected to the generator shaft grounding wire and is used to collect the generator shaft current signal in real time.

4. The generator shaft voltage and shaft current online monitoring device according to claim 1, characterized in that: It also includes an alarm unit, which is communicatively connected with the control unit; The control unit is also used to generate a generator shaft voltage alarm signal and a generator shaft current alarm signal; and send the generated generator shaft voltage alarm signal and the generator shaft current alarm signal to the alarm unit; The alarm unit is used to receive the generator shaft voltage alarm signal and the generator shaft current alarm signal sent by the control unit and to make corresponding alarms respectively.

5. The generator shaft voltage and shaft current online monitoring device according to claim 4, characterized in that: The control unit generates a generator shaft voltage alarm signal and a generator shaft current alarm signal, including the following steps: The control unit compares the real-time monitoring data of the generator shaft voltage and the real-time monitoring data of the generator shaft current with the alarm thresholds set by the control unit; If the real-time monitoring data of the generator shaft voltage exceeds the set alarm threshold, a generator shaft voltage alarm signal is generated; If the real-time monitoring data of the generator shaft current exceeds its set alarm threshold, a generator shaft current alarm signal is generated.

6. The generator shaft voltage and shaft current online monitoring device according to claim 4, characterized in that: The alarm unit includes a relay and an indicator light, and the relay and the indicator light are circuit-connected; The generator shaft current alarm signal includes a generator shaft current over-high alarm signal, and the generator shaft voltage alarm signal includes a generator shaft voltage over-high alarm signal and a generator shaft voltage under-low alarm signal; After the alarm unit receives the generator shaft current over-high alarm signal, the generator shaft voltage over-high alarm signal or the generator shaft voltage under-low alarm signal sent by the control unit, it controls the relay contacts to operate and the indicator light to light up.

7. The generator shaft voltage and shaft current online monitoring device according to claim 1, characterized in that: It also includes a storage unit; the storage unit is communicatively connected with the control unit; The control unit is also used to send the generator shaft voltage real-time monitoring data and the generator shaft current real-time monitoring data to the storage unit; The storage unit is used to receive and store the real-time monitoring data of the generator shaft voltage and the real-time monitoring data of the generator shaft current sent by the control unit to form the historical monitoring data of the generator shaft voltage and the historical monitoring data of the generator shaft current.

8. The generator shaft voltage and shaft current online monitoring device according to claim 1, characterized in that: It also includes a display unit; the display unit is communicatively connected with the control unit; The control unit is also used to send the generator shaft voltage real-time monitoring data and the generator shaft current real-time monitoring data to the display unit in real time; The display unit is used to receive in real time the generator shaft voltage real-time monitoring data and the generator shaft current real-time monitoring data sent by the control unit; The generator shaft voltage real-time monitoring data and the generator shaft current real-time monitoring data are respectively converted into frequency spectrum characteristic data and then displayed.

9. The generator shaft voltage and shaft current online monitoring device according to claim 8, characterized in that: It also includes an analog input and output unit; the analog input and output unit is provided with an analog input interface and an analog output interface, and the analog input interface and the analog output interface are respectively connected to the control unit for communication; The analog input and output unit is used to connect the external input analog signal to the control unit through the analog input interface; the real-time monitoring data of the generator shaft voltage and the real-time monitoring data of the generator shaft current generated by the control unit are output as analog output signals through the analog output interface to the external system for display; The control unit is also used to send the external input analog signal to the display unit; the display unit is also used to receive and display the external input analog signal sent by the control unit.

10. The generator shaft voltage and shaft current online monitoring device according to claim 1, characterized in that: The control unit is connected to the host computer through the communication unit, and the control unit sends the real-time monitoring data of the generator shaft voltage and the real-time monitoring data of the generator shaft current to the host computer in real time through the communication unit.

Images