CN112506114A - Railway signal external power network monitoring device based on DSP chip - Google Patents
Railway signal external power network monitoring device based on DSP chip Download PDFInfo
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- 238000005070 sampling Methods 0.000 claims description 15
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- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B19/00—Programme-control systems
- G05B19/02—Programme-control systems electric
- G05B19/04—Programme control other than numerical control, i.e. in sequence controllers or logic controllers
- G05B19/042—Programme control other than numerical control, i.e. in sequence controllers or logic controllers using digital processors
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
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- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B2219/00—Program-control systems
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Abstract
The invention provides a railway signal external power network monitoring device based on a DSP chip, which comprises a DSP chip unit, a voltage acquisition circuit module, a current acquisition circuit module, a power supply module, a CAN bus and a monitoring station machine, wherein the voltage acquisition circuit module is connected with the power supply module; the DSP chip unit processes the collected phase voltage signals and current signals and calculates phase voltage effective values, phase voltage fundamental wave effective values, phase voltage harmonic effective values, phase current fundamental wave effective values, phase current harmonic effective values, phase power factors, phase frequency, total power, AB line voltage, BC line voltage, CA line voltage, AB voltage phase difference, BC voltage phase difference and CA voltage phase difference; then comparing the calculation result with an alarm threshold value, and generating phase failure, wrong sequence, power failure and instantaneous power failure alarm information for the abnormal external power grid state; and finally uploading the real-time parameters and alarm information of the external power network to a monitoring station machine. The device can timely alarm the abnormity of the railway signal external power network, and the safety of a railway system is ensured.
Description
Technical Field
The invention relates to the field of railway power grids, in particular to a railway signal external power grid monitoring device based on a DSP chip.
Background
The safe external power supply is the basic guarantee of the normal operation of a railway signal system and monitoring equipment, so that the quality of the input power supply of the external power supply is monitored in real time, an alarm is given in time when an abnormality is found, and the method is particularly necessary for guaranteeing the safe operation of the railway system, preventing accidents and analyzing accident reasons. The existing railway signal system does not have the functions.
In order to solve the above problems, people are always seeking an ideal technical solution.
Disclosure of Invention
In order to achieve the purpose, the invention adopts the technical scheme that: a railway signal external power network monitoring device based on a DSP chip comprises a DSP chip unit, a voltage acquisition circuit module, a current acquisition circuit module, a power supply module, a CAN bus and a monitoring station machine;
the power supply module is used for supplying power to the DSP chip unit; the DSP chip unit is in communication connection with the monitoring station machine through a CAN bus;
the voltage acquisition circuit module is used for acquiring phase voltage signals input by I, II paths of two paths of three-phase external power networks and transmitting the phase voltage signals to the DSP chip unit; the current acquisition circuit module acquires current signals input by I, II paths of two three-phase external power networks and transmits the current signals to the DSP chip unit;
the DSP chip unit is used for processing the collected phase voltage signals and current signals and respectively calculating phase voltage effective values, phase voltage fundamental wave effective values, phase voltage harmonic effective values, phase current fundamental wave effective values, phase current harmonic effective values, phase power factors, phase frequency, total power, AB line voltage, BC line voltage, CA line voltage, AB voltage phase difference, BC voltage phase difference and CA voltage phase difference; then the DSP chip unit is used for comparing the calculation result with an alarm threshold value and generating phase failure, error sequence, power failure and instant power failure alarm information according to the abnormal external power network state; and finally, the DSP chip unit uploads the real-time parameters and alarm information of the external power network to the monitoring station machine through the CAN bus.
Based on the above, the DSP chip unit is a digital signal processor with model number TMS320F 28335.
Based on the above, the voltage acquisition circuit module is provided with six voltage acquisition channels, and each voltage acquisition channel comprises a safety sampling module, a passive alternating current sampler, a signal conditioning circuit and an AD conversion channel which are connected in sequence.
Based on the above, the safety sampling module comprises a fusing fuse, a thermistor, a current limiting resistor and a TVS tube.
Compared with the prior art, the railway signal external power network monitoring device based on the DSP chip has outstanding substantive characteristics and remarkable progress, and particularly has the following advantages:
(1) the device has a wide measuring range. The device is as the professional equipment to railway signal external power network monitoring, and the line voltage range that can measure is 0 ~ 500V, and the looks voltage range is 0 ~ 300V, and the electric current range is: 0-100A, a frequency range of 0-60 Hz, and a power range of 0-30 kW.
(2) The device has higher sampling precision. Wherein, the voltage acquisition precision of the device is +/-1%; the current collection precision is +/-2%; the phase angle calculation precision is +/-1%; the frequency calculation precision is +/-0.5 Hz; the power calculation accuracy is ± 2%.
(3) The device has a high sampling frequency. The sampling period for external network voltage and current is 250ms, the sampling period for phase failure, error sequence and instantaneous power failure alarm is 50ms, and the acquisition period for instantaneous power failure waveform is less than or equal to 2.5 ms.
(4) The device can generate different alarms according to different railway signal external power grid abnormal conditions. Specifically, the device generates a voltage alarm and records when the difference between the input voltage and the rated voltage is greater than 15% of the rated voltage value or less than 20% of the rated voltage value. The input voltage is lower than 65% of the rated voltage value, and the device generates phase failure and power failure alarm and records when the time exceeds 1000 ms. When the input voltage is lower than 65% of the rated voltage value, the time exceeds 140ms, but does not exceed 1000ms, the device can generate an instant power-off alarm and record a fault waveform. For a three-phase input power supply, when the phase sequence is wrong, the device can generate wrong sequence alarm and record.
(5) The device adopts a digital signal processing technology, and can extract corresponding key parameters such as frequency, phase angle, active power, reactive power and the like according to the characteristics of the external power grid signal. And the sampling value, the calculation result and the alarm information CAN be uploaded to the monitoring station machine through the CAN bus, and the real-time data recording and playback functions and the alarm output function are realized through the monitoring station machine.
Drawings
FIG. 1 is a schematic diagram of the logic connection of the railway signal external network monitoring device based on the DSP chip provided by the invention.
Fig. 2 is a schematic diagram of a safety sampling circuit in the railway signal external network monitoring device based on the DSP chip according to the present invention.
Detailed Description
The technical solution of the present invention is further described in detail by the following embodiments.
Example 1
The embodiment provides a railway signal external power network monitoring device based on a DSP chip, which comprises a DSP chip unit, a voltage acquisition circuit module, a current acquisition circuit module, a power supply module, a CAN bus and a monitoring station machine, as shown in fig. 1 and 2;
the power supply module is used for supplying power to the DSP chip unit; the DSP chip unit is in communication connection with the monitoring station machine through a CAN bus;
the voltage acquisition circuit module is used for acquiring phase voltage signals input by I, II paths of two paths of three-phase external power networks and transmitting the phase voltage signals to the DSP chip unit; the current acquisition circuit module acquires current signals input by I, II paths of two three-phase external power networks and transmits the current signals to the DSP chip unit;
the DSP chip unit is used for processing the collected phase voltage signals and current signals and respectively calculating phase voltage effective values, phase voltage fundamental wave effective values, phase voltage harmonic effective values, phase current fundamental wave effective values, phase current harmonic effective values, phase power factors, phase frequency, total power, AB line voltage, BC line voltage, CA line voltage, AB voltage phase difference, BC voltage phase difference and CA voltage phase difference; then the DSP chip unit compares the calculation result with an alarm threshold value and generates phase failure, error sequence, power failure and instant power failure alarm information according to the abnormal external power network state; and finally, the DSP chip unit uploads the real-time parameters and alarm information of the external power network to the monitoring station machine through the CAN bus.
Specifically, the DSP chip unit is a digital signal processor with a model number of TMS320F 28335.
The DSP chip unit has 150MHz high-speed processing capacity, 32-bit floating point processing units, 6 DMA channels supporting ADC, McBSP, ePWM, XINTF and SARAM, has up to 18 paths of PWM outputs, 6 paths of TI-specific PWM outputs with higher precision (HRPWM), and has 3 32-bit timers, 16 paths of 12-bit ADC and two Controller Area Network (CAN) modules.
Meanwhile, in order to calculate and store sampling signals conveniently, the SDRAM chip and the NANDFLASH chip are expanded in a peripheral circuit of the DSP through an FMC interface, wherein the SDRAM chip is used for calculating voltage characteristic parameters, and the NANDFLASH chip is used for storing key parameter values of an external power network after calculation coefficients of channels and alarm generation. The device mainboard extracts characteristic parameters of the acquired signals through the TMS320F28335 chip and the peripheral circuit thereof, realizes analysis and calculation of each parameter of two paths of three-phase external power networks, and realizes output of calculation results and alarm information to the monitoring station machine through the CAN bus interface.
The device is provided with 6 voltage acquisition channels, and a safety sampling module of each voltage acquisition channel is shown in figure 2.
The following safety measures are adopted in the safety sampling module:
the fuse is arranged at the high end and the low end of the signal input, and can be instantly fused when the current is more than 200mA, so that the short circuit of the high end and the low end of the signal input is prevented.
The PTC thermistor is connected in series in the voltage division loop for protection, and when the loop of the input end is more than 20mA, the resistance value can be increased to a few M ohms within tens to hundreds of milliseconds until the PTC thermistor burns out an open circuit.
The metal oxide film resistor with 1M ohm power of 2W is adopted, so that after a strong voltage input is subjected to high-resistance current limiting, a weak voltage signal and a millivolt signal are sampled at the rear end.
The TVS tube and the passive alternating current sampler are matched in the rear-stage circuit, so that the rear-stage signal conditioning circuit is prevented from being damaged due to high-voltage impact, and the high-voltage resistance of the sampling module is improved by the measures.
In the aspect of PCB layout, the safety sampling circuit module adopts the following protection design:
the arrangement distance of the current-limiting resistors on the circuit board is more than 8mm, the wiring areas of the high-voltage part and the low-voltage part are strictly distinguished, the interval between two wirings of the same analog quantity channel is more than 5mm, and the interval between input line bonding pads of different analog quantity channels is more than 5 mm.
And a protection design method of an isolation groove with the width larger than 1mm is adopted at the place which does not meet the safety clearance.
The device is provided with 6 current acquisition channels, 6 current transformers are used for acquiring three phase currents of two external power networks respectively, output signals of the current transformers are input into a signal conditioning circuit, are filtered and amplified by the signal conditioning circuit and then are input into an AD conversion channel 7-AD conversion channel 12 of the TMS320F28335, and the TMS320F28335 samples and calculates each AD conversion channel and then outputs each phase current value of the external power network.
The device adopts direct current 24V power supply, a DC/DC module with the isolation voltage reaching 3000V is adopted in the device to generate a DC5V power supply, and a DC5V power supply generates a DC1.8 power supply for a DSP core and a DC3.3V power supply for a DSP external circuit through a power chip TPS767D 318.
The device provides 4 LED indicator lamps outwards, and the power indicator lamps are used for indicating the working state of the power supply; the working indicator light is used for indicating the state of an external power grid, the working indicator light flashes for a second time when the state of the external power grid is normal, and the working indicator light flashes quickly when the device has alarm output; the CAN transmitting indicator lamp is used for indicating the CAN bus transmitting state; the CAN receiving indicator lamp is used for indicating the receiving state of the CAN bus.
Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present invention and not to limit the same; although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art will understand that: modifications to the specific embodiments of the invention or equivalent substitutions for parts of the technical features may be made; without departing from the spirit of the present invention, it is intended to cover all aspects of the invention as defined by the appended claims.
Claims (4)
1. The utility model provides a railway signal external network monitoring devices based on DSP chip which characterized in that: the intelligent monitoring system comprises a DSP chip unit, a voltage acquisition circuit module, a current acquisition circuit module, a power supply module, a CAN bus and a monitoring station machine;
the power supply module is used for supplying power to the DSP chip unit; the DSP chip unit is in communication connection with the monitoring station machine through a CAN bus;
the voltage acquisition circuit module is used for acquiring phase voltage signals input by I, II paths of two paths of three-phase external power networks and transmitting the phase voltage signals to the DSP chip unit; the current acquisition circuit module acquires current signals input by I, II paths of two three-phase external power networks and transmits the current signals to the DSP chip unit;
the DSP chip unit is used for processing the collected phase voltage signals and current signals and respectively calculating phase voltage effective values, phase voltage fundamental wave effective values, phase voltage harmonic effective values, phase current fundamental wave effective values, phase current harmonic effective values, phase power factors, phase frequency, total power, AB line voltage, BC line voltage, CA line voltage, AB voltage phase difference, BC voltage phase difference and CA voltage phase difference; then the DSP chip unit is used for comparing the calculation result with an alarm threshold value and generating phase failure, error sequence, power failure and instant power failure alarm information according to the abnormal external power network state; and finally, the DSP chip unit uploads the real-time parameters and alarm information of the external power network to the monitoring station machine through the CAN bus.
2. The railway signal external network monitoring device based on the DSP chip as claimed in claim 1, wherein: the DSP chip unit is a digital signal processor with a model number of TMS320F 28335.
3. The railway signal external network monitoring device based on the DSP chip as claimed in claim 2, wherein: the voltage acquisition circuit module is provided with six voltage acquisition channels, and each voltage acquisition channel comprises a safety sampling module, a passive alternating current sampler, a signal conditioning circuit and an AD conversion channel which are connected in sequence.
4. The railway signal external network monitoring device based on the DSP chip as claimed in claim 3, wherein: the safety sampling module comprises a fusing fuse, a thermistor, a current limiting resistor and a TVS (transient voltage suppressor).
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| CN202011589797.5A CN112506114A (en) | 2020-12-29 | 2020-12-29 | Railway signal external power network monitoring device based on DSP chip |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113625187A (en) * | 2021-08-13 | 2021-11-09 | 青岛地铁集团有限公司运营分公司 | Subway power supply analysis protection device based on octopus algorithm |
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