Microelectronic phase-sensitive receiver

Abstract

The invention provides a microelectronic phase-sensitive receiver. The microelectronic phase-sensitive receiver is simple in structure, can accurately and reliably trigger a relay to work and achieves the abnormity alarm function and the like. According to the microelectronic phase-sensitive receiver, two measurement circuits with an MCU1 and an MCU2 as cores are the same in structure, local voltage and track voltage are connected to A / D input pins of the MCUs through miniature mutual inductors, the MCUs collect two paths of voltage waveforms of a period, the initial phase angles and the effective values of the two paths of signals are calculated through a Fourier transform algorithm, a phase difference is solved, logic judgment is carried out, square signals are output when the condition is met, amplification, isolation transmission and rectification filter are carried out on the square signals, and the square signals wait for selection and output. An MCU3 collects and calculates four paths of voltage, a result is compared with a processing result of the MCU1 and a processing result of the MCU2 respectively, whether the voltage is normal or not is judged, one path of voltage is selected according to a set strategy, an output voltage amphenol connector outputs direct current voltage to enable a 1700 relay to work, and an alarm signal is given out if necessary.

Description

technical field [0001] The invention relates to a signal detection and logic processing circuit (device) applicable to a railway system, which outputs a DC voltage to make a relay work, and realizes functions such as abnormal alarm. Background technique [0002] With the development of electrified railway and the advancement of science and technology, the receiving equipment of electrified railway 25HZ phase-sensitive track circuit has experienced the development process from mechanical binary equipment to electronic binary equipment. [0003] 1. Mechanical binary equipment [0004] For example, JRJC170 / 240 binary two-position track relay is specially used in electrified railway stations, 25HZ phase-sensitive track circuit, and is manufactured by Shenyang Signal Factory and Xi'an Signal Factory of the Ministry of Railways. This equipment volume is big and heavy, once caused the jamming phenomenon of equipment, the Ministry of Railways has proposed the requirement of reformi...

AI Technical Summary

Problems solved by technology

[0007] 1. JXW-25A is a single-set use type, that is, one track circuit is equipped with one receiver. The advantage is that the construction investment is small, and it is easy for the construction unit to accept. The disadvantage is that once the components are defective, it is easy to cause traffic accidents.

However, we concluded that this solution still has insurmountable shortcomings: (1) It needs to use a larger transformer in its circuit structure, the primary side is directly connected to the rail voltage, and there is no series resistance at the input end, so the input impedance is low (400 ohms)

(2) There are many types of DC power supplies, including 24V, 9V, and 5V, and linear integrated voltage regulator circuits such as 7805 and 7809 are used, which consume a lot of power

(3) There are many types and large quantities of discrete components and small-scale integrated circuits, including discrete diodes, triodes, photocouplers, small-scale CMOS circuits, and small-scale TTL circuits, resulting in low board utilization and increased failure rates.

(4) The MCU used is a basic type with weak functions

(5) In the phase difference measurement method, the sine wave of the track voltage and the local voltage is first converted into a square wave, and then the phase is judged. This strategy uses many components and the effect is not good, and the anti-interference performance is poor. When the large 50HZ voltage interferes, the waveform will be distorted, which will cause a large measurement error

(6) Although two sets of the same circuit are used, there is no arbitration mechanism, and the final result generation mechanism is not perfect

(7) Due to the sine wave-rectangular wave transformation, the specific value of the input voltage cannot be measured, and there are defects in judging whether the voltage is normal. Therefore, only the phase difference can be carried out for the three elements of phase difference, local voltage and rail voltage. judge

Images