CN201029000Y

CN201029000Y - Unbalanced propulsion current analyzer

Info

Publication number: CN201029000Y
Application number: CNU2007201008805U
Authority: CN
Inventors: 王国荣
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-03-29
Filing date: 2007-03-29
Publication date: 2008-02-27
Anticipated expiration: 2017-03-29

Abstract

The utility model discloses an imbalance traction current analyzer, consisting of a tester and a palm computer PDA which is connected with the tester through a blue tooth communication circuit of the tester. The tester consists of an input voltage and current regulating circuit, a voltage current 12 position quantizer, a singlechip circuit, a RS232 connector circuit, a cell charging circuit, a reference source and a second electricity power source. The utility model adopts independent structure to ensure the safety of testing personnel; the tester is controlled by the singlechip and samples the input signals with the frequency of 1 KHZ through a three way 12 position D/A converter and sends the collected sample to the palm computer PDA according to the rate of 115200 bps through the blue tooth; the palm computer PDA analyzes and displays the field data in time, catches instant circuit malfunction and stores a large amount of test data.

Description

Unbalanced traction current analyzer

Technical Field

The utility model relates to an unbalanced traction current analyzer for real-time supervision, the electric fault analysis of electric railway rail traction current.

Background

In literature reports of relevant unbalanced current testers in Henan, beijing and the like, the Zhengzhou iron road bureau Zhengzhou science and technology research institute is used for detecting the tester of the traction current of the steel rails of the electrified railway, the detected result only contains 50HZ traction current, the currents of two steel rails can be simultaneously tested and directly compared, the test is accurate, and the fault of a track circuit caused by unbalanced traction current can be conveniently found; the tester for measuring the traction current of the railway electrification section track circuit on line by Beijing railway bureau Beijing scientific research institute comprises a battery box, a sampling mechanism, a computer and a display system; zhengzhou research institute Dan Zhenwu thesis, brief GD-1 type unbalanced current tester design philosophy and basic structure, the test equipment includes measuring the rail current sensor and tester sampled, its circuit is by inputting, partial pressure, amplitude limiting, matching, filtering, amplifying and revealing to make up; zhengzhou railway bureau construction center engineer Peng Xiangguo, introduces an intelligent unbalanced traction current measurement analysis recorder, which has three measurement input ports, is equipped with two special current clamps, can simultaneously perform 50HZ frequency selection measurement on two paths of current and one path of voltage under the coordination of hardware and software, and has 14-hour test record storage capacity and test record playback function; however, the data storage device cannot process sampled data in real time, does not have an intelligent analysis function, is not beneficial to troubleshooting, is not beneficial to carrying and transporting due to an integrated structure, is short in data storage time, does not have a wireless communication function, and stored data are difficult to derive.

Disclosure of Invention

The to-be-solved technical problem of the utility model is to provide an adopt split type structure, can calculate unbalanced current and unbalanced coefficient in real time and judge whether it exceeds standard, the unbalanced traction current analysis appearance that utilizes bluetooth to carry out the communication.

The utility model provides a technical scheme that above-mentioned problem adopted is: unbalanced draws current analysis appearance, it comprises test machine and the palm computer PDA who adopts bluetooth communication circuit and link to each other, its characterized in that: the tester consists of an input voltage and current conditioning circuit, a voltage and current 12-bit quantizer, a single chip circuit, an RS232 interface circuit, a battery charging circuit, a reference source and a secondary power supply, wherein the output end of the input voltage and current conditioning circuit is connected with the input end of the voltage and current 12-bit quantizer, the single chip circuit, the voltage and current 12-bit quantizer, the RS232 interface circuit and the Bluetooth communication circuit are connected in two directions, the output end of the battery charging circuit is connected with the input ends of the reference source and the secondary power supply, and the output ends of the reference source and the secondary power supply are respectively connected with the input ends of the voltage and current 12-bit quantizer, the input voltage and current conditioning circuit, the single chip circuit and the Bluetooth communication circuit.

The utility model discloses the technological progress who gains is: the utility model adopts the split structure design, which ensures the safety of the tester; the testing machine is controlled by a singlechip, samples an input signal at the frequency of 1KHZ through three paths of 12-bit analog-to-digital converters, and simultaneously transmits sampled data to the PDA of the palm computer in a wireless mode through Bluetooth at the rate of 115200 bps; the PDA analyzes and displays the field data in real time, can capture instant circuit faults, can store a large amount of test data, can lead the data into a computer for storage or manufacture into an optical disk for query and playback, has the functions of storing a station plane diagram, an outdoor structure diagram, an outdoor wiring diagram and the like, and can add or delete drawings according to actual needs; in the test process, the numerical values of the two paths of current and the unbalance coefficient can be displayed, and the two paths of current curves and the unbalance coefficient calculation curve can be displayed simultaneously; the intelligent analysis function is provided, and the imbalance coefficient is automatically calculated according to the test data.

Drawings

The present invention will be described in further detail with reference to the accompanying drawings and examples.

FIG. 1 is a schematic block diagram of a testing machine of the present invention;

fig. 2 is a circuit diagram of the input voltage and current conditioning circuit of the testing machine of the present invention;

fig. 3 is a circuit diagram of a 12-bit quantizer for voltage and current of the testing machine of the present invention;

FIG. 4 is a circuit diagram of the single chip microcomputer of the testing machine of the present invention;

fig. 5 is a circuit diagram of the RS232 interface circuit and the bluetooth communication circuit of the testing machine of the present invention;

fig. 6 is a circuit diagram of a secondary power supply and a battery charging circuit of the testing machine of the present invention;

fig. 7 is a diagram of the data processing software structure of the PDA of the palm computer of the present invention.

Detailed Description

As shown in fig. 1-7, the unbalanced traction current analyzer is composed of a tester and a palm-top computer PDA connected with the tester through a bluetooth communication circuit of the tester, wherein the tester is composed of an input voltage and current conditioning circuit, a voltage and current 12-bit quantizer, a single chip circuit, an RS232 interface circuit, a battery charging circuit, a reference source, a secondary power supply and a bluetooth communication circuit, the output end of the input voltage and current conditioning circuit is connected with the input end of the voltage and current 12-bit quantizer, the single chip circuit, the voltage and current 12-bit quantizer, the RS232 interface circuit and the bluetooth communication circuit are connected in two directions, the output end of the battery charging circuit is connected with the input ends of the reference source and the secondary power supply, and the output ends of the reference source and the secondary power supply are respectively connected with the input ends of the voltage and current 12-bit quantizer, the input voltage and current conditioning circuit, the single chip circuit and the bluetooth communication circuit. The input voltage and current conditioning circuit consists of 3 paths of voltage and current conversion circuits, the first path consists of resistors R40-R50, capacitors C23, C30, C40, C41, C45-C47, C57, diodes D12, D13, voltage-stabilizing tubes D8, D9, resistors R24, R25, R27 and an amplifier U12, the resistors R48, R49 and R50 are connected in parallel and then connected in series with the resistors R47, R46, R45, R44, R43, R42, R41 and R40 in sequence to be connected to the

pins

2 and 3 of the amplifier U12, the capacitors C46 and C47 are connected in series to be connected to the

pins

2 and 3 of the amplifier U12, the serial nodes of the capacitors C46 and C47 are grounded, the resistors R24 and R25 are connected in series to be connected to the

pins

2 and 3 of the amplifier U12, the serial nodes of the resistors R24 and R25 are grounded, the negative pole of the voltage-stabilizing tube D8 and the positive pole of the voltage-stabilizing tube D9 are connected to the pin 2 of the amplifier U12, the positive pole of the diode D12 is connected in parallel to the power supply pin V12, the negative pole of the diode D12 is connected to be connected to the ground of the amplifier U5, the resistor R23 and the diode V13, the resistor R23 is connected in parallel to be connected to the amplifier U13, the ground, the resistor C23 and the amplifier U13; the second path consists of resistors R51-R61, capacitors C31, C39, C42-C44, C48, C49, C58, diodes D10 and D11, voltage-regulator tubes D6 and D7, resistors R22, R23 and R26 and an amplifier U18, and the connection mode is the same as that of the first path; the third path consists of resistors R28-R32, capacitors C59, C50-C56, diodes D15 and D16, voltage-regulator tubes D5 and D14 and an amplifier U12, and the connection mode is the same as that of the first path. Resistors R14 and R15 and a crystal oscillator X2 of a voltage-current 12-bit quantizer are connected to

pins

10 and 11 of a serial counting/frequency divider U13 in parallel, one ends of a resistor R16 and a capacitor C36 are connected with one end of the crystal oscillator X2, a capacitor C37 is connected with the other end of the crystal oscillator X2, the other ends of the capacitors C36 and C37 are grounded,

pins

6, 14, 13 and 15 of the serial counting/frequency divider U13 are respectively connected with

pins

12, 14, 15 and 11 of a multi-way analog switch U7, the pin 13 output of the multi-way analog switch U7 is connected to a pin 3 of a trigger U4A,

pins

4 and 6 of the trigger U4A are grounded, the pin 2 and a pin 5 of the trigger U4A are connected, the pin 1 output of the trigger U4A is connected with a pin 2 at the input end of a trigger U14A, the pin 15 of the trigger U14A is connected with a power supply Vcc through a resistor R10, the pin 15 of the trigger U14A is grounded through a capacitor C27, the pin 4A of an output pin 6 of a conversion chip U19, the trigger U14A is connected with a pin B7B, and the output pin 14B of a trigger U14B is connected with a power supply of a single chip through a resistor B, and a trigger U14B, and a trigger U14B is connected with a trigger U14B, and a trigger U14B through a trigger U14B, the single chip microcomputer U14B, the power supply is connected with a power supply; the first route of the AD conversion circuit consists of an AD conversion chip U19, resistors R33 and R34, a capacitor C62 and a latch U20, the output end of the input voltage and current conditioning circuit is connected with

pins

1 and 2 of the input end of the AD conversion chip U19 through the resistor R33, the

pins

1 and 2 of the input end of the AD conversion chip U19 are grounded through the resistor R34, the

pins

1 and 2 of the input end of the AD conversion chip U19 are connected with an analog ground through the capacitor C62, the output end of the AD conversion chip U19 is output to the single chip through the latch U20, and the connection of the other two routes of the AD conversion circuit is the same as that of the first route; the power supply high-frequency filter capacitors C12, C17, C18, C20, C32, C33, C34, C35, C38, C60, C61, C63 and C64 are all connected between a power supply Vcc and the ground. The singlechip circuit comprises a singlechip U1, an address decoder U8, a crystal oscillator circuit consisting of a crystal oscillator X1 and capacitors C1 and C2, a reset circuit consisting of an inverter U3, a resistor R6 and a capacitor C15, and power supply high-frequency filter capacitors C10, C11 and C14; the output end of the singlechip U1 is connected with the input end of an address decoder U8, the output end of the address decoder U8 is connected with the input ends of an AD conversion chip U19 and a latch U20, the pin 3 at the input end of the phase inverter U3 is connected with a power supply Vcc through a resistor R6, the pin 3 at the input end of the phase inverter U3 is grounded through a capacitor C15, and the pin 4 at the output end of the phase inverter U3 is connected with the pin 4 of the singlechip U1. The RS232 interface circuit and the Bluetooth communication circuit are characterized in that a pin 1 of a serial port chip U2 is connected with a pin 3 of the serial port chip U2 through a capacitor C5, a pin 4 of the serial port chip U2 is connected with a pin 5 of the serial port chip U2 through a capacitor C7, a pin 16 of the serial port chip U2 is connected with a pin 15 of the serial port chip U2 through a capacitor C9, the pin 15 of the serial port chip U2 is grounded, a pin 10 of the serial port chip U2 is connected with a power supply Vcc through a resistor R5, a pin 2 of the serial port chip U2 is grounded through a capacitor C6, a pin 6 of the serial port chip U2 is grounded through a capacitor C8, a pin 2 of a pin 7 connector J3 and one end of a jumper connector JMP1 of the serial port chip U2, a pin 2 of the other end J5 of the JMP1, a pin 3 of a pin 8 connector J3 of the serial port chip U2 and one end of the jumper connector JMP2, a pin 3 of the other end J5 of the JMP2, a pin 13 of the serial port chip U2 is connected with a pin 7 of the jumper connector J3, a pin 14 of the serial port chip U2, and a pin 8 connector J5 of the jumper connector J5 of the power supply connector J5, and a pin B-5 of the serial port connector J5. The pin 1 of a connector J2 of the battery charging circuit is connected to the positive electrode of a battery BT1 through resistors R11, R12 and R13 and a diode D3 in sequence, the

pins

2 and 3 of the connector J2 are simultaneously connected with an analog ground and a ground, the pin 1 of the connector J2 is connected with the pin 3 of a connector J4 through the diode D2, the positive electrode of the battery BT1 is connected with the pin 3 of the connector J4 through the diode D1, the negative electrode of the battery BT1 is connected with the analog ground and the ground, the pin 4 of the connector J4 is respectively connected with one end of resistors R17, R19 and R21, the negative electrode of a voltage regulator tube D4 and the pin 4 of a power field effect chip U16, the other end of the resistor R17 is connected with the base electrode of a triode Q1 through a resistor R20, the emitter of the triode Q1 is grounded, the node of the resistor R17 and the resistor R20 is connected with the pin 1 of the low-voltage detection chip U5, the other end of the resistor R19 is connected with the pin 5 of the connector J4, the other end of the resistor R21 is connected with the pin 5 of the connector J4, the collector of the triode Q1 and the pin 3 of the power field effect chip U16, the positive electrode of the voltage regulator tube D4 is connected with one end of the resistor R18 and the pin 2 of the low-voltage detection chip U5, the other end of the resistor R18 is grounded, the pin 3 of the low-voltage detection chip U5 is grounded, the

pins

1, 2, 5 and 6 of the power field effect chip U16 are all connected with the power supply V +, and the capacitors C3 and C21 are all connected between the power supply V + and the node of the analog ground and the ground; a voltage stabilizing block V1 of a reference source and a secondary power supply and a capacitor C4 form a first power supply circuit, a pin 1 of the voltage stabilizing block V1 is connected with a power supply V +, a pin 2 of the voltage stabilizing block V1 is grounded, a pin 3 of the voltage stabilizing block V1 is output to be connected with a power supply V-B, and the capacitor C4 is connected between the power supply V-B and the ground; the voltage stabilizing block V2 and the capacitor C16 form a second power supply circuit, the connection mode is the same as that of the first power supply circuit, the voltage stabilizing block V3, the resistor R38, the resistor R39, the resistor R66, the potentiometer RP2 and the capacitor C24 form a third power supply circuit, a pin 3 of the voltage stabilizing block V3 is connected with a power supply V +, a pin 2 of the voltage stabilizing block V3 is output to a power supply +5V, the power supply +5V is sequentially connected with the resistor R38, the potentiometer RP2 and the resistor R39 to be grounded, the capacitor C24 is connected between the power supply +5V and the ground, the resistor R66 is connected between the power supply +5V and the ground, a node of the resistor R38 and the potentiometer RP2 is connected with a pin 1 of the voltage stabilizing block V3 and an adjusting end of the potentiometer RP2, the voltage stabilizing block V4, the resistor R36, the R37, the R67, the potentiometer RP1 and the capacitor C29 form a fourth power supply circuit, and the connection mode is the third power supply circuit. The PDA software of the palm computer consists of a data analysis module, a sampling data processing module, a data storage module, a calculation and analysis module and a data display module, and is used for calculating an unbalance coefficient after processing the data of the traction current and the voltage collected by the tester and analyzing the unbalance coefficient. The data analysis module is used for extracting the traction current and voltage data transmitted to the PDA through the Bluetooth communication circuit. The sampling data processing module is used for carrying out spectrum analysis on the traction current and voltage sampling data and extracting 50HZ effective data. And processing the sampled data by sampling fast Fourier positive and inverse transformation. The data storage module is used for storing the original sampling data of the traction current and the traction voltage. The calculation analysis module is used for calculating effective values of the 50HZ traction current and voltage data, calculating an unbalance coefficient of the two-path traction current, and analyzing and alarming the unbalance coefficient.

The imbalance coefficient calculation formula is as follows:

the data display module is used for displaying the waveforms of the traction current and the voltage, the effective value curves of the traction current and the voltage and the unbalance coefficient curve.

The utility model discloses the theory of operation as follows: the rail current signal is detected by a clamp type current transformer, sent to a voltage and current conditioning circuit, converted into a 0-5V voltage signal by a sampling resistor, filtered by a capacitor, limited by a diode and a voltage stabilizing tube, sent to an amplifier for amplification, and output to an AD conversion circuit.

As shown in fig. 3, the 3-chip 12-bit AD converter quantizes the input voltage of 0 to 5V, the sampling frequency of 3 channels is 1khz, sampling pulses of ADC are generated by U4, U7, U13, U14A, R, R15, R16, C36, C37, X2, R10, and C27, after the ADC conversion is finished, interrupt signals are generated by U14B, R, and C28, and the known single chip microcomputer reads ADC data; u10, U11, U19 are three same 12 bit ADCs, sample three routes input voltage. U15, U17, U20 are latches, when the singlechip reads the low 8 bit of 12 bit ADC, the high 4 bit is latched, the singlechip reads the high 4 bit from the latch, the three current voltage values read by the singlechip U1 are transmitted to the PDA for processing at 115200bps by the Bluetooth communication circuit, the data acquisition is started and stopped, the PDA informs the singlechip by the Bluetooth communication circuit, as shown in figure 4, U8 is an address decoder for reading the address of the three 12 bit ADCs by the singlechip, and U3, R6, C15 form a singlechip power-on reset circuit.

As shown in fig. 5, the RS232 interface is used for upgrading the program of the single chip on the tester. When the Bluetooth communication circuit is not arranged, the testing machine can perform data transmission with a computer through an RS232 interface, U2 completes level conversion of a UART signal and an RS232 signal of a single chip, and the Bluetooth communication circuit builds a data transmission and instruction issuing wireless channel between the PDA and the testing machine.

As shown in fig. 6, V3, R36, R37, RP1, C29, R67 generate 2.5V reference power to the 3 instrumentation amplifiers in fig. 2 as reference power, V4, R38, R39, RP2, C24, R66 generate 5V voltage to the 3 ADCs in fig. 3 as analog power, and V2, C16 generate digital 5V power on board. V1 and C4 generate a Bluetooth module 5V power supply, and D4, U5, U16, Q1, R17, R18, R19, R20 and R21 are automatically powered off when the battery pack is lower than 6.5V; BT1 is a battery pack formed by 6 sections of No. 5 nickel-hydrogen rechargeable batteries, when a 9V/1A direct current transformer is connected into J2, BT1 is charged through R11, R12, R13 and D3, and meanwhile, the circuit on the board is powered through D2, and when no external direct current transformer is available, BT1 supplies power to the circuit on the board through D1.

The software adopts unique data processing software to process the data of the traction current and the voltage collected by the tester, then calculates the unbalance coefficient, analyzes the unbalance coefficient, displays the final result by the waveform of the traction current and the voltage, the effective value curve of the traction current and the voltage and the unbalance coefficient curve, or communicates with the computer through a serial communication port (a serial port cable or Bluetooth wireless), and stores the original sampling data.

Claims

1. The unbalanced traction current analyzer consists of a testing machine and a palm computer PDA connected with the testing machine through a Bluetooth communication circuit of the testing machine, and is characterized in that: the tester consists of an input voltage and current conditioning circuit, a voltage and current 12-bit quantizer, a single chip circuit, an RS232 interface circuit, a battery charging circuit, a reference source, a secondary power supply and a Bluetooth communication circuit, wherein the output end of the input voltage and current conditioning circuit is connected with the input end of the voltage and current 12-bit quantizer, the single chip circuit, the voltage and current 12-bit quantizer, the RS232 interface circuit and the Bluetooth communication circuit are connected in two directions, the output end of the battery charging circuit is connected with the input ends of the reference source and the secondary power supply, and the output ends of the reference source and the secondary power supply are respectively connected with the input ends of the voltage and current 12-bit quantizer, the input voltage and current conditioning circuit, the single chip circuit and the Bluetooth communication circuit.

2. The unbalanced traction current analyzer of claim 1, wherein: the input voltage and current conditioning circuit consists of 3 paths of voltage and current conversion circuits, the first path consists of resistors R40-R50, capacitors C23, C30, C40, C41, C45-C47, C57, diodes D12, D13, voltage-stabilizing tubes D8, D9, resistors R24, R25, R27 and an amplifier U12, the resistors R48, R49 and R50 are connected in parallel and then connected in series with the resistors R47, R46, R45, R44, R43, R42, R41 and R40 in sequence to be connected to the pins 2 and 3 of the amplifier U12, the capacitors C46 and C47 are connected in series to be connected to the pins 2 and 3 of the amplifier U12, the serial nodes of the capacitors C46 and C47 are grounded, the resistors R24 and R25 are connected in series to be connected to the pins 2 and 3 of the amplifier U12, the serial nodes of the resistors R24 and R25 are grounded, the negative poles of the voltage-stabilizing tubes D8 and the positive pole of the voltage-stabilizing tube D9 are connected to the pin 2 of the amplifier U12, the positive pole of the diode D12 is connected to the power supply pin V12, the negative pole of the diode D12 is connected in parallel to be connected to the amplifier U5, the diode D13, the power supply pin 12 is connected to be connected to the ground, the diode D23, the resistor R23 and the resistor U13 to be connected in parallel to be connected to the amplifier U12, the amplifier U5 and the ground, the diode V23; the second path consists of resistors R51-R61, capacitors C31, C39, C42-C44, C48, C49, C58, diodes D10 and D11, voltage-regulator tubes D6 and D7, resistors R22, R23 and R26 and an amplifier U18, and the connection mode is the same as that of the first path; the third path consists of resistors R28-R32, capacitors C59, C50-C56, diodes D15 and D16, voltage-regulator tubes D5 and D14 and an amplifier U12, and the connection mode is the same as that of the first path.

3. An unbalanced traction current analyser as claimed in claim 1 wherein: resistors R14 and R15 and a crystal oscillator X2 of a voltage-current 12-bit quantizer are connected to pins 10 and 11 of a serial counting/frequency divider U13 in parallel, one ends of a resistor R16 and a capacitor C36 are connected with one end of the crystal oscillator X2, a capacitor C37 is connected with the other end of the crystal oscillator X2, the other ends of the capacitors C36 and C37 are grounded, pins 6, 14, 13 and 15 of the serial counting/frequency divider U13 are respectively connected with pins 12, 14, 15 and 11 of a multi-way analog switch U7, the pin 13 output of the multi-way analog switch U7 is connected to a pin 3 of a trigger U4A, pins 4 and 6 of the trigger U4A are grounded, the pin 2 and a pin 5 of the trigger U4A are connected, the pin 1 output of the trigger U4A is connected with a pin 2 at the input end of a trigger U14A, the pin 15 of the trigger U14A is connected with a power supply through a resistor R10, the pin 15 of the trigger U14A is grounded through a capacitor C27, the pin 4A of the trigger U14A is connected with a pin 6 of a conversion chip U19, the pin B is connected with a pin 14B, the pin 14B of the trigger U7 is connected with a power supply of a single chip microcomputer through a pin 14B, and a pin 14B is connected with a pin Vcc through a pin 14B, and a pin 14B, the pin 14B is connected with a pin 14B, the pin 14B of the trigger U7 of the trigger U14B is connected with a trigger U14B, the trigger U7; the first route of the AD conversion circuit consists of an AD conversion chip U19, resistors R33 and R34, a capacitor C62 and a latch U20, the output end of the input voltage and current conditioning circuit is connected with pins 1 and 2 of the input end of the AD conversion chip U19 through the resistor R33, the pins 1 and 2 of the input end of the AD conversion chip U19 are grounded through the resistor R34, the pins 1 and 2 of the input end of the AD conversion chip U19 are connected with an analog ground through the capacitor C62, the output end of the AD conversion chip U19 is output to the single chip through the latch U20, and the other two routes of the AD conversion circuit are connected with the same circuit as the first route; the power supply high-frequency filter capacitors C12, C17, C18, C20, C32, C33, C34, C35, C38, C60, C61, C63 and C64 are all connected between a power supply Vcc and the ground.

4. An unbalanced traction current analyser as claimed in claim 1 wherein: the single chip microcomputer circuit comprises a single chip microcomputer U1, an address decoder U8, a crystal oscillator circuit consisting of a crystal oscillator X1 and capacitors C1 and C2, a reset circuit consisting of a phase inverter U3, a resistor R6 and a capacitor C15, and power supply high-frequency filter capacitors C10, C11 and C14; the output end of the single chip microcomputer U1 is connected with the input end of an address decoder U8, the output end of the address decoder U8 is connected with the input ends of an AD conversion chip U19 and a latch U20, the pin 3 at the input end of the phase inverter U3 is connected with a power supply Vcc through a resistor R6, the pin 3 at the input end of the phase inverter U3 is grounded through a capacitor C15, and the pin 4 at the output end of the phase inverter U3 is connected with the pin 4 of the single chip microcomputer U1.

5. The unbalanced traction current analyzer of claim 1, wherein: the RS232 interface circuit and the Bluetooth communication circuit are connected with a pin 3 of a serial port chip U2 through a capacitor C5 by a pin 1 of the serial port chip U2, a pin 4 of the serial port chip U2 is connected with a pin 5 of the serial port chip U2 through a capacitor C7, a pin 16 of the serial port chip U2 is connected with a pin 15 of the serial port chip U2 through a capacitor C9, the pin 15 of the serial port chip U2 is grounded, a pin 10 of the serial port chip U2 is connected with a power supply Vcc through a resistor R5, a pin 2 of the serial port chip U2 is grounded through a capacitor C6, a pin 6 of the serial port chip U2 is grounded through a capacitor C8, a pin 7 of the serial port chip U2 is connected with a pin 2 of a connector J3 and one end of a jumper connector JMP1, a pin 2 of the other end of the JMP1, a pin 3 of the serial port chip J3 and one end of the jumper connector JMP2, the other end of the JMP2 is connected with a pin 3 of the serial port J5, a pin 7 of the serial port chip J3 of the serial port chip U2, a pin 14 of the serial port chip J2, a power supply pin of the serial port chip J3 is connected with a pin B-5 and a pin of the jumper connector J5 of the power supply connector J5, and a pin B-5 of the serial port connector J5.

6. The unbalanced traction current analyzer of claim 1, wherein: the 1 pin of a connector J2 of a battery charging circuit is connected to the anode of a battery BT1 through resistors R11, R12, R13 and a diode D3 in sequence, the 2 and 3 pins of the connector J2 are connected with a simulation ground and the ground simultaneously, the 1 pin of the connector J2 is connected with the 3 pin of a connector J4 through a diode D2, the anode of the battery BT1 is connected with the 3 pin of the connector J4 through a diode D1, the cathode of the battery BT1 is connected with the simulation ground and the ground, the 4 pin of the connector J4 is connected with one end of resistors R17, R19 and R21, the cathode of a voltage regulator D4 and the 4 pin of a power field effect chip U16 respectively, the other end of the resistor R17 is connected with the base electrode of a triode Q1 through a resistor R20, the emitter electrode of the triode Q1 is grounded, the node of the resistor R17 and the resistor R20 is connected with the 1 pin of a low-voltage detection chip U5, the other end of the resistor R19 is connected with the 5 pin of the connector J4, the 5 pin of the other end of the resistor R21 is connected with the 5 pin of the J4, the collector electrode of the triode Q1 and the 3 pin of the power field effect chip U16, one end of the resistor R18 and one end of the power detection chip D4 is connected with the power source of the power source C6, the power source of the power source chip C6, the power source and the power source of the power chip U2 and the power detection chip, the power source chip V6, the power source chip U2, the power chip V6, the power source chip V6 are connected with the ground, the power source C6, the ground, and the power source of the resistor R2; a voltage stabilizing block V1 of a reference source and a secondary power supply and a capacitor C4 form a first power supply circuit, a pin 1 of the voltage stabilizing block V1 is connected with a power supply V +, a pin 2 of the voltage stabilizing block V1 is grounded, a pin 3 of the voltage stabilizing block V1 is output to be connected with a power supply V-B, and the capacitor C4 is connected between the power supply V-B and the ground; the voltage stabilizing block V2 and the capacitor C16 form a second power supply circuit, the connection mode is the same as that of the first power supply circuit, the voltage stabilizing block V3, the resistor R38, the resistor R39, the resistor R66, the potentiometer RP2 and the capacitor C24 form a third power supply circuit, the pin 3 of the voltage stabilizing block V3 is connected with the power supply V +, the pin 2 of the voltage stabilizing block V3 is output to the power supply +5V, the power supply +5V sequentially passes through the resistor R38, the potentiometer RP2 and the resistor R39 to be grounded, the capacitor C24 is connected between the power supply +5V and the ground, the resistor R66 is connected between the power supply +5V and the ground, the node of the resistor R38 and the potentiometer RP2 is connected with the pin 1 of the voltage stabilizing block V3 and the adjusting end of the potentiometer RP2, the voltage stabilizing block V4, the resistor R36, the R37, the R67, the potentiometer RP1 and the capacitor C29 form a fourth power supply circuit, and the connection mode is the third power supply circuit.