CN201653537U - Vibration Acquisition Analyzer - Google Patents

Abstract

The utility model provides a vibration collection analyzer, which includes: a vibration signal conditioning device, which receives the vibration signal of the measured rotating machine from the vibration sensor, and processes the vibration signal to generate signals corresponding to different sensor types. Multi-channel vibration conditioning signals, select one vibration conditioning signal output according to the type of vibration sensor and sampling requirements; the key phase signal processing device receives the key phase signals of the rotating machinery under test, and processes the key phase signals to generate key phase pulses signal; a phase-locking frequency multiplication device, which receives the key phase pulse signal, and processes the key phase pulse signal to generate a frequency multiplication signal; a vibration signal sampling device, which receives the frequency multiplication signal and the output vibration conditioning signal, and uses the frequency multiplication signal to adjust the output vibration The conditioning signal is sampled to generate sample data; the control processing device is used to receive the key-phase pulse signal, and start the sampling process under the trigger of the key-phase pulse signal.

Description

Vibration Acquisition Analyzer

technical field

The utility model relates to the field of vibration detection of power equipment, in particular to a vibration collection analyzer.

Background technique

In recent years, in order to alleviate the power shortage, major power companies have continuously increased power investment and expanded new large-scale generating units. Due to the influence of design, manufacture, installation, operation, maintenance and other aspects, as well as the characteristics of large capacity, high parameters and complexity of the unit itself, the actual availability rate of large units is not high, and there is a big gap compared with similar units abroad . At present, the unplanned shutdown and unplanned output reduction of the unit due to the unstable operation state of the unit caused by factors such as the vibration defect of the main and auxiliary machines are still increasing.

Using multi-channel portable vibration acquisition and analysis instruments, using vibration state detection and vibration data analysis technology, can effectively evaluate the unit status, diagnose defects and faults, and realize unit startup, shutdown, load changes, vibration faults and other The main means of vibration state testing and analysis under special working conditions. At present, there are many multi-channel vibration acquisition and analyzer products at home and abroad, most of which use single-chip microcomputer, microprocessor or embedded technology, and are widely used in engineering practice of unit debugging and vibration control. However, due to different design ideas and technical applications, these instrument systems have more or less certain defects or deficiencies, mainly including:

(1) Insufficient signal processing capability of key phase

The key phase signal is generally picked up by the eddy current sensor by opening a groove of a certain width on the surface or welding a metal strip; or by attaching a reflective sheet on the shaft to be picked up by a photoelectric sensor; it may also be directly drawn from the on-site TSI equipment buffer interface. The key phase signal is a periodic signal of one pulse per revolution of the shaft. Due to the different sensors used or acquisition methods and different key phase marking methods, the signal may be a positive pulse or a negative pulse; the voltage level of the signal is also different, which may be 3.5 ~5V pulses or pulses above 5V; the ratio of the key phase mark to the circumference of the shaft will cause the duty cycle of the pulse signal to be different, which may be a 50% square wave or a small duty cycle of 0.1% level Pulse signal.

In the vibration monitoring and analysis of the steam turbine generator set, the key phase signal plays a vital role as a phase reference. In the vibration signal sampling, the key phase pulse is used as the CPU external interrupt signal. When the key phase pulse arrives, the vibration signal adjustment is started. Periodic sampling, so that the starting point of sampling is the position of the key phase, and the high point phase obtained from the sampling signal through FFT calculation is the phase difference relative to the position of the key phase, so this phase can be used as the basis for dynamic balance weight calculation. Commonly used key-phase signal sensors include photoelectric, eddy current and other types. The key-phase signal derived from the TSI (turbine supervisory instruments, turbine monitoring tool) system may also be a TTL (Transistor-Transistor Logic, logic gate circuit) pulse signal.

In order to accurately extract the key phase signal from the background noise and vibration signal, the key phase processing circuit needs to have a certain trigger comparison voltage setting and duty cycle adaptability. The key phase signal trigger voltage of most existing analytical instruments is designed to be fixed , cannot be adjusted automatically, and it is difficult to meet the recognition of key-phase signals of different signal levels, and the existing filtering method has insufficient adaptability to a small duty cycle (such as 0.01% level). Therefore, most of the existing analytical instruments do not have the self-adaptive capability of multiple key phase signal access;

(2) Insufficient access to vibration signals

Due to different unit structures and configurations, there are various types of vibration sensors installed on site, including eddy current, velocity, acceleration, and ICP (Integrated Circuits Piezoelectric, piezoelectric sensors with built-in integrated circuits), and the sensitivity of sensors also varies greatly. There are analytical instruments that are designed specifically for one type of sensor signal, and few can fully support a variety of sensors. Most of the vibration channel capacity of existing analytical instruments is insufficiently designed, generally single, double, 4, 6, 8 and 16 channels, and a single instrument cannot meet the comprehensive vibration monitoring of a large unit;

(3) Insufficient sample collection capacity:

Key-phase synchronization, multi-channel simultaneous, and full-period sampling are the basic requirements for vibration acquisition and analysis instruments, but most analysis instruments only provide conventional fixed-length samples (such as: 8 periods of 1024 points) acquisition, because few instruments have customizable Long sample, fine spectrum analysis function.

(4) Insufficient communication capability of host computer interface:

The vibration sample data collected by the vibration acquisition analyzer generally needs to be uploaded to the host computer (usually a laptop) through a certain interface, so as to realize functions such as status monitoring, vibration analysis, data storage and management, and historical query. The main interface methods of existing analytical instruments include serial port, EPP (Enhanced Parallel Port, enhanced parallel port) interface, USB interface, field bus interface (such as Controller Area Network, referred to as CAN bus).

The communication rate of the serial port is low, which cannot meet the real-time transmission of large-capacity sample data; although the EPP parallel port has a certain data transmission bandwidth, computers equipped with EPP parallel ports, especially notebook computers, are very difficult to find and have poor versatility; It has a high communication rate and a simple interface, but the USB communication used for vibration data transmission often needs to install a specially developed data transmission driver, which does not have good software versatility, and the USB communication driver with poor performance is directly It affects the reliability of the system; the communication rate of the field bus interface is also high, but its communication protocol design is mainly short messages (within 100B), which are mainly used in the transmission of a small amount of data for field intelligent instruments and meters. The vibration signal transmission as a unit often requires a large number of data packet decomposition, and even needs to expand the existing standard protocol, which brings about the lack of versatility.

Utility model content

The purpose of the utility model is to provide a vibration acquisition analyzer based on an embedded system architecture.

In order to achieve the above purpose, the embodiment of the present utility model provides a vibration acquisition analyzer, the vibration acquisition analyzer includes: a vibration signal conditioning device, used to receive the vibration signal of the rotating machine under test from the vibration sensor, and The vibration signal is processed to generate multiple vibration conditioning signals corresponding to different sensor types, and one channel of vibration conditioning signal output is selected according to the type of the vibration sensor and sampling requirements; the key phase signal processing device is used to receive the key of the rotating machine under test. A phase signal, processing the key phase signal to generate a key phase pulse signal; a phase lock frequency multiplication device for receiving the key phase pulse signal, processing the key phase pulse signal to generate a frequency multiplier signal; vibration signal sampling A device for receiving the frequency multiplier signal and the output vibration conditioning signal, using the frequency multiplier signal to sample the output vibration conditioning signal to generate sample data; a control processing device for receiving the key phase pulse signal, The sampling process is started under the trigger of the key phase pulse signal.

The vibration acquisition analyzer of the utility model overcomes the lack of functions of the existing multi-channel vibration monitoring analyzer in terms of key phase signal processing, vibration channel access, sample collection and upper computer interface communication, etc., and meets the comprehensive vibration monitoring requirements of large-scale units. monitoring analysis needs.

Description of drawings

Fig. 1 is the functional schematic diagram of the vibration acquisition analyzer of the utility model embodiment;

FIG. 2 is a detailed schematic diagram of the vibration signal conditioning device 10 according to the embodiment of the present invention;

FIG. 3 is a detailed schematic diagram of the key phase signal processing device 20 according to the embodiment of the present invention;

Fig. 4 is the system schematic diagram of the 24 channel vibration acquisition analyzer of the utility model embodiment;

Fig. 5 is the circuit block diagram of the vibration signal conditioning module of the utility model embodiment;

Fig. 6 is the detailed vibration signal conditioning circuit of the embodiment of the present invention;

Fig. 7 is the circuit block diagram of the key phase signal processing module of the utility model embodiment;

Fig. 8 is the detailed key phase signal conditioning circuit of the embodiment of the present invention;

Fig. 9 is the functional block diagram of the high-speed AD sampling module of the utility model embodiment;

Fig. 10 is a functional block diagram of the rotational speed acquisition module of the utility model embodiment;

Fig. 11 is a schematic diagram of the use of the key phase signal in the embodiment of the present invention;

Fig. 12 is the flow chart that adopts the vibration acquisition analyzer of the present embodiment to carry out vibration acquisition analysis;

Fig. 13 is a schematic diagram of the communication process between the vibration acquisition analyzer and the host computer.

Detailed ways

The embodiment of the utility model provides a vibration collection analyzer. The vibration acquisition analyzer includes a vibration signal conditioning device, a key-phase signal processing device, a phase-locked frequency multiplication device, a vibration signal sampling device, a rotational speed acquisition device and a control processing device, and data is transmitted between these devices through a bus.

The vibration signal conditioning device in this embodiment can adapt to vibration signals from different types of sensors, and output corresponding conditioning signals according to sensor types and actual sampling requirements. The key-phase signal processing device of this embodiment can process key-phase signals of different amplitudes and duty ratios, and the processed key-phase signals are divided into three paths for use: the first path is sent to the phase-locked frequency multiplier for frequency multiplication processing, The generated frequency multiplied signal will be used to sample the vibration signal; the second channel is sent to the control processing device, and the control processing device starts a continuous sampling process after receiving the signal; the third channel is sent to the speed acquisition device, which is collected by the speed An apparatus generates rotational speed data of a rotating machine.

Below in conjunction with accompanying drawing, the utility model specific embodiment is described in detail:

Fig. 1 is the function schematic diagram of the vibration acquisition analyzer of the embodiment of the present utility model. As shown in Figure 1: the vibration acquisition analyzer includes: a vibration signal conditioning device 10, which is used to receive the vibration signal of the tested rotating machinery transmitted by the vibration sensor, and process the vibration signal to generate multiple signals corresponding to different sensor types. Vibration conditioning signal, according to the type of the vibration sensor and sampling requirements, select one vibration conditioning signal output; the key phase signal processing device 20 is used to receive the key phase signal of the rotating machine under test, and process the key phase signal to generate Key-phase pulse signal; phase-locking frequency multiplication device 30, for receiving said key-phase pulse signal, processing said key-phase pulse signal to generate frequency multiplication signal; vibration signal sampling device 40, for receiving said frequency multiplication signal and the output vibration conditioning signal, the frequency multiplier signal is used to sample the output vibration conditioning signal to generate sample data; the control processing device 50 is used to receive the key phase pulse signal, and under the trigger of the key phase pulse signal Start the sampling process. The control processing device can be an embedded network module, such as Intel 386.

In a preferred embodiment, the vibration acquisition analyzer further includes: a rotational speed acquisition device 60, configured to receive the key-phase pulse signal, process the key-phase pulse signal to generate rotational speed data of the tested rotating machine, The speed data is an important reference data for vibration analysis. The control processing device 50 is further configured to process the key phase pulse signal to generate vibration characteristic parameters, and send the sample data, rotational speed data and vibration characteristic parameters to the host computer.

The vibration signal conditioning device 10 of this embodiment includes multiple vibration conditioning channels. Each vibration conditioning channel is used to receive a vibration signal from a vibration sensor, and process the vibration signal to generate multiple vibration conditioning signals corresponding to different sensor types. Through one vibration conditioning signal output. Corresponding to multiple vibration conditioning channels, the vibration signal sampling device 40 of this embodiment includes multiple sampling channels for simultaneously sampling the vibration conditioning signals output by the multiple vibration conditioning channels.

Fig. 2 is a detailed schematic diagram of the vibration signal conditioning device 10 according to the embodiment of the present utility model. As shown in Fig. 2 , the vibration signal conditioning device 10 includes: a DC signal extraction unit 201 for extracting a DC signal from the vibration signal; The original signal acquisition unit 202 is used to filter and amplify the vibration signal to obtain the original AC signal; the primary integral signal acquisition unit 203 is used to integrate the AC signal to obtain the primary integral signal; the secondary integral signal acquisition unit 204 , for re-integrating the primary integral signal; obtaining a secondary integral signal; a multiplexer 205, configured to select from the direct current signal, the alternating current signal, the primary integral signal and the Select one signal output from the quadratic integral signal.

Fig. 3 is the refinement schematic diagram of key phase signal processing device 20 of the embodiment of the present utility model, as shown in Fig. 3, this key phase signal processing device 20 comprises: Bi-directional voltage comparison unit 301, is used for adjusting according to the amplitude of key phase signal Trigger voltage value, using the trigger voltage to perform peak-peak detection on the key-phase signal; pulse signal generating unit 302, used to adjust the parameters of the trigger circuit according to the duty cycle of the key-phase signal, to the peak-peak detected The signal is triggered by the rising edge J-K to generate a stable TTL pulse signal.

In a preferred embodiment, the key phase signal processing device 20 includes at least two key phase signal processing channels, each key phase signal processing channel is used to receive the key phase signal of the rotating machine under test, and the key phase signal Processing is performed to generate key-phase pulse signals. The key-phase signal processing device 20 in FIG. 3 further includes: a key-phase signal selection unit, configured to select one output from at least two generated key-phase pulse signals according to the instruction of the control processing device.

The working principle of the vibration acquisition analyzer of the embodiment of the present utility model will be described in detail below with a 24-channel vibration acquisition analyzer.

Fig. 4 is a schematic diagram of the system of the 24-channel vibration acquisition analyzer of the embodiment of the present invention. As shown in Figure 4: The 24-channel vibration acquisition analyzer is based on an embedded network module, and is composed of modules such as high-speed synchronous AD sampling, speed acquisition, vibration signal conditioning, and key phase signal processing through a simplified ISA bus. The 24-channel vibration acquisition analyzer includes: 3 8-channel vibration signal conditioning modules, 2 redundant key-phase signal processing modules, phase-locked frequency multiplication module, pulse width counting speed acquisition module, 2 16-channel high-speed AD sampling modules and based on Embedded network module for Intel 386. The embedded network module communicates with the upper computer through 10M Ethernet, and each module is connected to the simplified ISA bus provided by the embedded network module. The working principle of each component is explained separately as follows:

(1) Vibration signal conditioning module

Three 8-channel vibration signal conditioning modules receive 24 channels of external vibration signals, and each vibration signal conditioning channel includes high/low-pass filtering, signal amplification, DC/AC separation, first-level integration, and second-level integration circuits. The circuit extracts signals such as DC components, original waveforms, primary integral waveforms, or secondary integral waveforms in successive stages, and connects to the multi-channel selection circuit. According to the sensor type and acquisition needs, the required signals are selected and sent to the high-speed synchronous AD sampling module for acquisition. Type sensor, vibration signal conditioning module can provide constant current source power supply. Each module integrates 8 channels of vibration signal conditioning, and finally provides 24 channels of processing and output of vibration signals from various types of sensors.

The types of sensors used to measure the vibration of rotating machinery are generally eddy current sensors, speed sensors, acceleration sensors or ICP acceleration sensors, where the ICP sensor needs to provide a constant current source for power supply. Vibration measurement is most concerned with the displacement value of the vibration. For eddy current sensors, it is necessary to remove the gap voltage through DC blocking to obtain the AC signal of vibration displacement; for speed sensors, the displacement signal can only be obtained after one integration; for acceleration or ICP If the sensor needs to be integrated twice, the displacement signal can be obtained. In addition, the output voltage levels of different types of sensors are also different. The eddy current sensor is a V-level signal, while the speed sensor is a mV-level signal, and the acceleration signal is smaller.

Fig. 5 is a circuit block diagram of the vibration signal conditioning module. As shown in Figure 5: After the externally connected vibration signal is processed by high-pass and low-pass filtering, it enters the primary integration circuit and the secondary integration circuit successively. For the eddy current sensor signal, the DC extraction circuit is used to extract the gap voltage DC signal in the original signal. According to the power supply instruction, the DC extraction circuit provides corresponding constant current power supply for the ICP acceleration sensor connection. DC signal, filtered original waveform signal, primary integration, secondary integration and other signals are selected according to the CPU channel type instruction, and one of them is selected by the multi-channel selection circuit, and sent to high-speed AD sampling.

Figure 6 is a detailed vibration signal conditioning circuit, including: constant current power supply circuit 601, gap voltage processing circuit 602, second-order high-pass filter and second-order low-pass filter circuit 603, original signal acquisition circuit 604, primary integration circuit 605, secondary An integration circuit 606 and a vibration type selection circuit 607 .

As shown in Figure 6, the vibration signal SIN1 is subjected to second-order high-pass, second-order low-pass filtering, and DC blocking processing to obtain an AC waveform signal BSIN1 after removing interference and DC bias; BSIN1 is amplified to obtain the original waveform signal that can be used for sampling VW1. The original waveform signal VW1 is the original vibration displacement signal for the eddy current sensor, the original vibration speed signal for the speed sensor, and the original acceleration signal for the acceleration sensor.

The AC signal BSIN1 passes through the integration circuit once again to obtain the AC signal V1. The AC signal V1 is the vibration displacement signal for the speed sensor and the vibration speed signal for the acceleration sensor. The AC signal V1 passes through the secondary integration circuit to obtain the AC signal VV1, and the AC signal VV1 is the vibration displacement signal to the acceleration sensor. Different amplification factors are set for each level of circuit to ensure that the final signal output to the AD sampling module is a standard signal (-10V ~ 10V). The gap voltage processing circuit 602 can extract the DC bias in the eddy current sensor signal, that is, the gap voltage GAP1. For ICP type sensors, the circuit is designed with a constant current source power supply circuit 601 for gating input channels according to CPU instructions.

In different stages of the circuit, the DC signal GAP1, the original AC signal VW1, the primary integral signal V1 and the secondary integral signal VV1 are derived for different sensor inputs. Each channel has 4 signals, which are connected to the vibration type selection circuit 607 (for example, an analog multi-way selection switch), and the software system selects different signals through the configured sensor type and sends them to the high-speed AD sampling module for collection. For example, when it is necessary to collect the eddy current signal gap, select the DC signal GAP1; when it is necessary to collect the original displacement waveform of the eddy current sensor or the original velocity waveform of the speed sensor or the original acceleration waveform of the acceleration sensor, select the original waveform signal VW1; it is necessary to collect the displacement of the speed sensor waveform or the velocity waveform of the acceleration sensor, select the primary integral signal V1; if the displacement waveform of the acceleration sensor needs to be collected, select the secondary integral signal VV1.

(2) Key phase signal processing module

Because the instantaneous speed of the rotating machinery under test changes at any time, especially during the start and stop process, if the trigger signal is generated by the timer according to the multiple of the speed frequency, the collected speed is not necessarily the speed at the time of sampling, and the obtained multiplied trigger The signal is far less accurate than the phase-locked loop hardware tracking, and there may be more or less points per cycle. The final signal spectrum analysis may cause leakage, especially affecting the accuracy of vibration phase measurement. Therefore, in this embodiment, the key phase signal is used for synchronous sampling.

The key-phase signal processing module of this embodiment provides a redundant two-way key-phase signal processing circuit, through redundant processing, the reliability of key-phase signal processing is improved, and the redundant key-phase channel can be selected according to the instructions of the embedded network module . In practical applications, more than two redundant processing circuits may also be provided. The externally connected key-phase signal is filtered, DC-blocked, amplified, bi-directional voltage comparison circuit and trigger circuit to generate a stable TTL key-phase pulse.

Fig. 7 is a circuit block diagram of a key-phase signal processing module. As shown in Figure 7, the key phase signal is firstly preprocessed by filtering, DC blocking, amplification, etc., and then a stable TTL key phase pulse signal is obtained after bidirectional comparison, peak-to-peak detection circuit and rising edge J-K trigger. The stable TTL key-phase pulse signal will be divided into three outputs: one is sent to the phase-locked frequency multiplier circuit to generate a stable and accurate n-multiplied frequency signal of the speed frequency, which is used as a sample synchronous AD sampling trigger signal; one is sent to the pulse width counting speed The acquisition circuit collects the rotational speed of the shaft; one line is used as an external interrupt signal of the streamlined ISA bus, which is sent to the CPU to trigger and start a continuous sample acquisition.

FIG. 8 is a schematic diagram of an actual and effective key-phase signal processing circuit, including: filter preprocessing circuit 801, bidirectional comparison circuit 802, rising edge J-K trigger circuit 803, phase-locking frequency multiplication circuit 804, and light-emitting indication circuit 805. It should be noted that the edge J-K flip-flop is only a common form of the flip-flop, and other flip-flops can also be used in this embodiment. The selection of the edge J-K flip-flop here mainly considers the edge transition of the phase-healthy signal processing circuit and mainly checks the signal. .

As shown in Figure 8, the actual key-phase signal RPM in the filter preprocessing circuit 801 may be a positive pulse or a negative pulse with a certain amplitude, and enters the bidirectional comparison circuit 802 (also called peak-to-peak detection circuit). Among them: the positive comparison circuit provides a trigger voltage of about 2V to compare with the key phase pulse, and only the positive pulse exceeding this voltage can pass; the reverse comparison circuit provides a trigger voltage of about -2V to compare with the key phase pulse, only lower than this voltage The negative pulse can pass. The two detection signals are synthesized into an effective key phase pulse signal RPM2. The trigger voltage can be appropriately adjusted according to actual needs, for example, the parameters of resistors and capacitors in the circuit can be adjusted according to needs, and adjusted to other thresholds, such as 2.5V, 3V, 1.5V, etc. In this embodiment, the trigger voltage threshold of the bidirectional comparison circuit 802 is selected at about 2V, considering that the amplitude of the actually connected phase-health signal is generally above 3.5V.

After the key-phase pulse signal RPM2 passes through the rising edge J-K trigger circuit 803 , a stable TTL pulse signal RPM1 can be obtained for use by the CPU and the subsequent phase-locked frequency multiplication circuit 804 . At the same time, the TTL pulse signal of the key phase and the stable signal of the phase-locked multiplier will be sent to the light-emitting indicating circuit 805 for external status indication. The two-way comparison circuit 802 can adapt to the polarity of the actual signal, as long as the signal reaches a certain range (such as the range of 2V to 20V, the voltage range is determined according to the maximum possible range of the actual phase-healthy signal, that is, the phase-healthy signal of the eddy current sensor), Both positive and negative pulses can be extracted accurately. At the same time, the two-way comparison circuit 802 is used in conjunction with the rising edge J-K trigger circuit 803 to adjust the circuit parameters (such as the value of resistance and capacitance) to identify the key-phase signal with a very small duty cycle (above 0.1%).

(3) Phase-locked multiplier:

In the vibration signal processing of rotating machinery, in order to avoid the occurrence of spectrum leakage and aliasing, which will affect the vibration signal analysis, it is generally necessary to sample the vibration signal for the entire cycle, that is, based on the rotation speed cycle, the sampling cycle is the multiplier of the rotation speed cycle , with a sample length of multiple full periods. The TTL level key phase signal extracted by the key phase signal processing module is sent all the way to the phase-locked frequency multiplication circuit to generate an adjustable frequency multiplier signal (PPL) of the key phase signal, which provides an external sampling trigger signal for the synchronous AD sampling module. The rotational speed is collected by means of pulse counting through the phase-healthy pulse, and the phase-healthy signal generates a pulse for each revolution of the unit, representing the rotational speed cycle. The signal generated by phase-locking and frequency multiplication produces n (such as 128) pulses for each revolution, and the sample collection is triggered by the frequency multiplication signal. If the length of the sample collected is a multiple of n, it is the sample of an integer rotational speed cycle. . This is also the function of the phase-locked frequency multiplication circuit (tracking the rotation speed cycle, ensuring that the generated AD acquisition trigger signal is n times the stable original pulse). The role of the rotational speed data, on the one hand, is used for data storage, working condition recording and display; on the other hand, it can also decide whether to use hardware frequency multiplication circuit to generate AD acquisition trigger signal. For the software acquisition process, see the description below.

The core of the phase-locked frequency multiplication circuit is 4046 chip, and the VCO voltage-controlled oscillator of 4046 phase-locked loop is a multivibrator with high linearity, which can produce a very good symmetrical square wave output. In the circuit, two timing counters cooperate with the 4046 phase-locked loop circuit. Both Timer4 (T in 804) and Timer7 (PLL in 804) use the output of 4046 as the Clock signal, while Gate is connected to high level, Timer4 mode Set to 3, initial value 512, Timer7 mode set to 2, initial value 4, by changing the initial value of Timer4, you can get a phase-locked multiplier pulse signal with adjustable frequency, the multiplication number is: Timer4 initial value/Timer7 initial value.

(4) High-speed synchronous AD sampling module:

The functional block diagram of the high-speed AD sampling module is shown in Figure 9. The module is based on a simplified ISA bus, and consists of an amplifier, a multi-channel sample-and-hold switcher, a high-speed A/D converter, a 256K buffer memory, an internal timing counter, and an address decoding device, gating circuit, DMA/interrupt controller, etc. The AC vibration waveform signal output by the vibration signal conditioning module is amplified and collected sequentially by four 4-channel A/D chips through sample-hold and multi-channel switching. The rate of A/D chip is 300KHz, and the sampling result of AD chip is controlled by FIFO circuit, and enters the 256K buffer memory sequentially to realize independent sampling. The embedded system software only needs to set parameters such as sampling mode and sample length, and after starting sampling, a sample collection can be realized by DMA mode or querying the sampling end flag.

The working mode of the high-speed AD sampling module includes internal timing interval triggering, external signal triggering and software triggering. In the case of a key-phase signal access, the key-phase signal processing circuit and the phase-locked frequency multiplication circuit can provide the AD sampling module with an external key-phase follow-up frequency multiplication trigger signal; if the key-phase signal is not connected, the software system can Set the AD sampling module to work in the internal timing interval sampling mode to ensure the collection of vibration signals. The high-speed synchronous AD sampling module is composed of two 16-channel high-speed AD sampling modules. The software system can adjust the working parameters of the AD sampling module according to the number of vibration channels actually connected. The large-capacity buffer memory of 256K can realize long sample, fine Chemical analysis sample data collection.

(5) Acquisition of rotational speed:

The rotational speed acquisition module is composed of multiple 16-bit timing counters. The key phase pulse signal extracted by the connected key phase signal processing module is converted into a square wave signal after being divided by 2, and then the pulse width is counted by cascading 16-bit timing counters at a clock frequency of 100k, so as to realize the accuracy of the rotating machinery under test. Acquisition and calculation of rotational speed. Rotating speed is an important working condition parameter of rotating machinery, especially in the process of starting and stopping, analyzing the curve of vibration changing with rotating speed is an important basis for fault analysis and vibration control.

In this embodiment, one of the TTL level key phase signals extracted by the key phase signal processing module is sent to the rotational speed acquisition circuit. The circuit includes two cascaded timing counters, and the rotational speed acquisition is realized by means of pulse width counting. The principle The block diagram is shown in Figure 10.

The key phase signal is connected to the timing counter Timer1 as a Clock (clock) signal, the Timer1 mode is set to 3, the initial value is 2, and the Gate is connected to the high level of VCC, that is, Timer1 is used as a frequency divider to convert the TTL key phase pulse into a frequency halved square wave signal. The square wave signal output by Timer1 is used as the Gate signal of Timer2, the Timer2 mode is set to 2, the initial value is set to 0xFFFF, and the Clock of Timer2 is connected to the 80KHz clock signal.

Figure 11 shows the comparison diagram of key phase signal, frequency multiplier signal, key phase 2 frequency division square wave signal and clock pulse width counting signal. As shown in Figure 11, at the high level of the square wave signal, an 80K clock is used to count down it. When the square wave signal is at a low level, the counting stops, and the software system reads out the count value, and the speed value can be obtained by simple calculation. . Because a 16-bit counter is used for pulse width counting, according to the working speed of a general steam turbine unit is 3000 rpm (50Hz), in order to avoid excessive error or count overflow, the frequency of Clock should not be too high or too low. The clock frequency used in this embodiment is 80KHz, which ensures that the count value is close to the maximum value of the 16-bit counter at a speed of 3000 rpm. The calculation relationship between pulse width count and speed is:

f=80000/(65536-N)

rpm=f*60

Among them: N is the read value of the counter, 65536 is the initial value of the 16-bit counter (the counter is counting down), that is, (65535-N) is the pulse width count value; f is the speed frequency; rpm is the speed, unit: rev/min .

(6) Embedded network module

The embedded network module is the core of the vibration acquisition analyzer. The embedded network module of this embodiment adopts Intel 386 microprocessor and 512K user Flash disk space, runs DOS system, provides streamlined ISA bus driver interface and integrates 10/100M fast Ethernet Network Interface. The network module runs special data acquisition, calculation, and data transmission programs, and simplifies the ISA bus driver interface to connect other modules of the system. Its Ethernet interface is used for high-speed, real-time data communication with the host computer.

Fig. 12 is a flow chart of vibration collection and analysis using the vibration collection analyzer of this embodiment. As shown in the figure: After completing the necessary system bus initialization, watchdog setting, network and hardware initialization, the software enters the main cycle of data acquisition, that is, setting the watchdog at a certain interval to ensure the reliable operation of the system; periodic reading And process the network commands issued by the host computer, such as sampling parameter settings and status reports, etc.; collect the speed at regular intervals; determine whether the key phase signal is connected through the collected speed (according to the aforementioned speed acquisition principle, when there is a healthy phase signal When accessing, the adjusted phase-healthy pulse enters the counter circuit of pulse width counting to have a count value. Therefore, it can be judged whether there is a phase-healthy signal connected according to whether the collected speed value is 0); Set the AD sampling module to work in the external trigger mode, and open the key phase interrupt; start the AD sampling process in the key phase interrupt processing program, and close the key phase interrupt at the same time, so as to ensure the sampling starting point of the key phase interrupt; In the case of phase access, set the internal clock parameters of the AD sampling module according to the set sampling frequency, so that it works in the internal timing interval sampling mode, and at the same time the software starts AD sampling; AD sampling automatically samples according to the set mode and sampling parameters, and collects data Enter the FIFO buffer memory sequentially under the control of the sequential circuit; the software system periodically reads the AD sampling end sign, if a sample sampling ends, the software sequentially reads the contents of the FIFO buffer memory, if the AD sampling times out within a certain period of time, Then the software system restarts a new sampling process; the sample data is calculated by DFT to obtain characteristic parameters such as vibration amplitude and phase; the speed, sample data and characteristic parameters are all uploaded to the upper computer system through the network interface for further processing, analysis and storage. storage.

Figure 13 shows the communication process between the vibration acquisition analyzer and the host computer. The acquisition analyzer provides sampling data transmission for the upper computer system through the 10/100M Ethernet interface, and the online computer system also realizes acquisition parameter setting, working mode adjustment, and operation status monitoring for the acquisition analyzer through this interface. In the network communication with the upper computer, the role of the acquisition instrument is a network server, which monitors the network connection of the upper computer at any time, and the upper computer is a network client. After connecting to the acquisition analyzer, the upper computer sets and controls the acquisition through network commands. analyzer work.

As shown in Figure 13: the acquisition analyzer monitors the network connection request at any time, and the upper computer sends the SetAcqParam command after the connection request is completed to set the parameters of the acquisition analyzer, such as the number of channels, each channel type, sample length, sampling frequency, etc. At the same time, the upper computer The computer sends the SetDataRefresh command to set the acquisition analyzer to actively upload the collected data; the acquisition analyzer works with the set sampling configuration, and the collected speed data, sample data, and characteristic data are uploaded at any time; the host computer can be turned on or off by setting the SetInfoReport flag Collect the working status report of the analyzer; the host computer can reset the IP address parameters of the analyzer through SetAddress; it can also reset the analyzer through the Restart command; when the host computer does not need to connect to the analyzer, it can actively close the network connection , the acquisition analyzer enters the network monitoring state again.

The vibration acquisition analyzer of the utility model embodiment can provide the following beneficial effects:

1. By providing up to 24 channels of vibration signal access, it can meet the comprehensive vibration monitoring and analysis needs of large units with 8 watts and 3 vibration signals per watt;

2. The vibration signal conditioning circuit provides multi-channel selection of signals such as DC, original vibration waveform, primary integral waveform and secondary integral waveform, and constant current source power supply capability, ensuring adaptation to different types of sensor signals such as eddy current, speed, acceleration, and ICP. sex;

3. Dual redundant key-phase processing circuits ensure the reliability of crucial key-phase signal processing;

4. Using bidirectional trigger voltage comparison technology, it can accurately extract the key phase signal, and adapt to the input of key phase sensor signals of different types such as photoelectricity, eddy current, and TTL with a lower duty cycle;

5. Large buffer, configurable, high-speed synchronous AD sampling module ensures long sample and fine spectrum analysis needs;

6. Sampling 10M/100M high-speed Ethernet host computer communication interface, with good versatility.

The above specific embodiments are only used to illustrate the present utility model, but not to limit the present utility model.

Claims (9)

1. a kind of vibration collection analyzer, is characterized in that, described vibration collection analyzer comprises: The vibration signal conditioning device is used to receive the vibration signal of the rotating machinery under test from the vibration sensor, and process the vibration signal to generate multiple vibration conditioning signals corresponding to different sensor types. According to the type and sampling of the vibration sensor One-way vibration conditioning signal output is gated on demand; The key phase signal processing device is used to receive the key phase signal of the rotating machine under test, and process the key phase signal to generate a key phase pulse signal; A phase-locked frequency multiplication device, configured to receive the key-phase pulse signal, and process the key-phase pulse signal to generate a frequency multiplier signal; A vibration signal sampling device, configured to receive the frequency multiplied signal and the output vibration conditioning signal, and use the frequency double signal to sample the output vibration conditioning signal to generate sample data; The control processing device is used to receive the key-phase pulse signal, and start the sampling process under the trigger of the key-phase pulse signal. 2. The vibration acquisition analyzer according to claim 1, wherein the vibration acquisition analyzer also includes: The rotation speed acquisition device is used to receive the key phase pulse signal, and process the key phase pulse signal to generate the rotation speed data of the rotating machine under test. 3. The vibration acquisition analyzer according to claim 2, characterized in that, The control processing device is also used to process the key phase pulse signal to generate vibration characteristic parameters, and send the sample data, rotational speed data and vibration characteristic parameters to the host computer. 4. The vibration acquisition analyzer according to claim 1, wherein the vibration signal conditioning device comprises: a multi-channel vibration conditioning channel; Each vibration conditioning channel is used to receive a vibration signal from a vibration sensor, process the vibration signal to generate multiple vibration conditioning signals corresponding to different sensor types, according to the vibration sensor type and sampling requirements connected to the channel Select one channel of vibration conditioning signal output. 5. The vibration acquisition analyzer according to claim 1, wherein the vibration signal conditioning device comprises: a DC signal extraction unit, configured to extract a DC signal from the vibration signal; an original signal acquisition unit, configured to filter and amplify the vibration signal to obtain an original AC signal; a primary integral signal acquisition unit, configured to integrate the AC signal to obtain a primary integral signal; a secondary integral signal acquisition unit, configured to re-integrate the primary integral signal; obtain a secondary integral signal; The multi-channel selection unit is used to select one signal output from the direct current signal, alternating current signal, primary integral signal and secondary integral signal according to the type of the vibration sensor and sampling requirements. 6. The vibration acquisition analyzer according to claim 4, characterized in that, The vibration signal sampling device includes multiple sampling channels for simultaneously sampling the vibration conditioning signals output by the multiple vibration conditioning channels. 7. The vibration acquisition analyzer according to claim 1, wherein the key phase signal processing device comprises: At least two key phase signal processing channels, each key phase signal processing channel is used to receive the key phase signal of the rotating machine under test, and process the key phase signal to generate a key phase pulse signal; The key-phase signal selection unit is configured to select one output from at least two key-phase pulse signals generated according to the instruction of the control processing device. 8. The vibration acquisition analyzer according to claim 1, wherein the key phase signal processing device comprises: a bidirectional voltage comparison unit, configured to adjust a trigger voltage value according to the amplitude of the key-phase signal, and use the trigger voltage to perform peak-to-peak detection on the key-phase signal; The stable pulse signal generation unit is used to adjust the parameters of the trigger circuit according to the duty cycle of the key phase signal, and perform rising edge J-K trigger on the signal after peak-to-peak detection to generate a stable TTL pulse signal. 9. The vibration acquisition analyzer according to claim 1, wherein the control processing device is an embedded network module.

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