CN206211889U - BLDCM Drive System - Google Patents

Abstract

A kind of BLDCM Drive System, it is made up of power circuit, micro control unit circuit, inverter driving circuit, hardware braking protection circuit, vibration voltage-multiplying circuit, detection circuit, AVR single chip, it is characterised in that：AVR single chip connection power circuit, micro control unit circuit, inverter driving circuit, hardware braking protection circuit, vibration voltage-multiplying circuit, detection circuit.The system has the advantages that simple circuit stability, practical safety, low cost.

Description

BLDCM Drive System

Technical field

The utility model is related to a kind of BLDCM Drive System based on AVR single chip control, particularly can be with Stall, excessively stream and under-voltage protection are realized, if system fault can start self-checking function, while user can be two in upgrading space The BLDCM Drive System of secondary exploitation.

Background technology

With the development of China's economic, electric automobile is progressed among huge numbers of families, and progressively instead of bicycle into It is one of vehicles that people have deep love for.Electric automobile not only price material benefit, and electrical energy drive is used, meet the green of country The view of development.But the dynamical system of electric automobile is one of key issue urgently to be resolved hurrily.Because external electric automobile drives Control system technical research is carried out already, and standardization is tended in terms of drive control device；But it is still complete in China data Kind, the stability of product, reliability and versatility etc. by contrast, still need to improve.

The content of the invention

In order to overcome the blank of above-mentioned existing domestic technique, the utility model provides a kind of permanent magnetism based on AVR single chip The control system of brshless DC motor, the system has that circuit is simple, performance safety, low cost and other advantages, is conducive to pure electronic Vehicle industrialization.

The utility model solves the technical scheme that its technical problem used：Hardware components using MEGA48 single-chip microcomputers as Control chip, inverter is made up of 6 MOSFET pipes.By circuit modules such as micro control unit circuit, inverter driving circuits Design, realizes the defencive functions such as the Based Intelligent Control and under-voltage protection, overcurrent protection, rotation-clogging protection of motor, reliably to electronic Vehicle motor and battery are protected, it is ensured that electric automobile is used and safety.System worked well voltage 72V, minimum operating voltage 65 V, the A of maximum operating currenbt 180, the kW of peak power output 18.Software section carries out modularization, systematization with high-level language And structured programming.

The beneficial effects of the utility model are：（1）With electronic, two kinds of mode of operations of automatic cruising：Under electric model, Control system can give voltage, normal power-up operating according to electric automobile pedal；Under automatic cruise mode, stepped on without slamming Plate, electric automobile can run according to setting speed；Two kinds of mode of operations can be switched by patten transformation button.（2）Work as system Error or position sensor, assistant sensor can enter Auto-Sensing Mode and show mistake when malfunctioning.（3）System can be realized Under-voltage protection, overcurrent protection, rotation-clogging protection.（4）The state of electric motor car can in real time be shown.

Brief description of the drawings

The utility model is further illustrated with reference to the accompanying drawings and examples.

Fig. 1 is hardware system block diagram of the present utility model.

Fig. 2 is MOSFET inverse changing driving circuits of the present utility model.

Fig. 3 is power circuit of the present utility model.

Fig. 4 is vibration voltage-multiplying circuit and pure hardware protection circuit of the present utility model.

Fig. 5 is working-flow figure of the present utility model.

Specific embodiment

In Fig. 1, it is the designed system hardware block diagram according to above-mentioned functions.

In fig. 2, the inverter driving circuit of MOSFET compositions is employed.（1）The control of half-bridge inverter is more complicated, Six groups of control signals are needed, the work of motor three-phase windings is also relatively independent, it is necessary to which three-phase current is controlled respectively.And full-bridge is inverse The control for becoming device is fairly simple, only needs three groups of individual control signals, and the biphase current of any instant conducting is equal, as long as to it In a phase current be controlled, a phase current is also under control in addition.Therefore the design is controlled using full bridge inverter The conducting of all phase.Inverter upper and lower bridge arm is all using N-channel MOS FET pipes in the design.P-type MOSFET pipes are due to technique Reason, parameter consistency is poor, expensive, and its internal resistance is bigger than N-channel MOS FET pipes, is lost also big.Therefore, it is current Brushless controller typically all constitutes a phase of inverter using two N-channel MOS FET pipes.（2）As shown in Fig. 2 due to by Limitation with voltage, top drive circuit cannot directly with TTL device matchings, therefore be used for by LM339 in circuit indirect Matching voltage, the LM339 output ends after matching（The pin of a phases 2, the pin of b phases 1, the pin of c phases 14）Level be respectively 12V effective status or Disarmed state more than 25V.When certain phase top drive circuit is effective, fieldtron VF1（Or VF3, VF5）Grid voltage 46V is not less than, the sufficiently conductive of FET, after conducting, X1 is just can guarantee that（Or X2, X3 voltage are identical with cell voltage）.By In the gate insulator grid easily breakdown destruction of MOSFET pipes, therefore gate-source voltage must not exceed positive and negative 20V.Electricity in parallel between grid source Resistance or Zener diode, to prevent gate-source voltage excessive.In the design, the 15V voltage-regulator diodes in the drive circuit of top DZ2, DZ4 and DZ6 are protection diode.Also protection circuit is added to prevent from being produced because of the mutation of voltage in switching process between drain-source Raw drain electrode peak voltage damages pipe, can use Zener diode nationality position.When the unexpected stalling suddenly of motor, machine winding produces wink Between high back voltage may damage power tube, so a high pressure resistant electric capacity in parallel on dc bus, female during hang-up The instantaneous pressure produced on line can be inhibited because electric capacity both end voltage can not be mutated.End line voltages drive circuit is used NE555 inside push-pull circuit, the pwm signal produced using single-chip microcomputer modulates bottom drive signal, and the signal after modulation is by electricity Resistance is coupled to bottom driving FET grid, controls FET conducting state.Because NE555 power consumptions in the drive circuit of bottom It is larger, it is therefore desirable to be that U8, U9 and U10 mix R22, R30 in Hall electric capacity C37, C39 and C45. end line voltages drive circuit, R38 is series connection gate resistance, is FET bottom Drive Protecting Circuit, can be eliminated in office by MOSFET electric capacity and the source circuit of grid one What series connection winding senses and the raw higher-order of oscillation.（3）By taking A phases as an example, top drives, when being output as low for 2 mouthfuls of LM339,12 Pin positive ending grounding so that Q1 base voltages 22V>Q1 is open-minded, and electric current flows through R19, and the sense of current is left positive right negative（So as to ensure Q1 Q2 shut-offs when opening）, VF1 grid voltages are 50V or so, and source voltage is 36V or so, and VF1 is open-minded；When 2 mouthfuls of outputs of LM339 For it is high when, Q1 shut-off, at this moment VF1 cut-off.Q2 and R18, R19, C26 composition active filter.Bottom drives, and is protected when by logic When the A phases bottom control signal ABTM inputs of shield are 1,12V useful signals are produced by bottom drive circuit so that VF2 is turned on. Meanwhile, the pwm signal of single-chip microcomputer output is sent to the RST ends of NE555, and bottom control signal is modulated.

In figure 3, the power unit of drive circuit includes two parts circuit：A part is by battery supply 36V, by three End voltage-stablizer LM7915 produces the -15V voltages of opposed power voltage, i.e. 36V-15V=21V to produce high driving for voltage-multiplying circuit Voltage；Another part is the+12V voltages produced by three terminal regulator LM7812, drives matching and bottom to drive for top Circuit.As shown in figure 3, in power circuit, according to the electric current of various pieces, the resistance of rational selection shunt resistance R14 and R45 And power, the electric current for directly flowing through Three-end voltage stabilizer is reduced, its caloric value is reduced, improve circuit stability.

In fig. 4,（1）In order to increase the reliability and security of control system, pure hardware braking protection circuit is devised. Braking circuit is by controlling the level state at the RST ends of oscillating circuit, voltage source needed for the conducting of indirect control top drive circuit. By the defencive function of LM339, when the systems are operating normally, by pull-up resistor, level is 12V to the voltage at test point 1, warp 22V voltage-regulator diodes are crossed, the level at test point 2 is in 34V or so, oscillating circuit normal work；When system excessively stream, pure hardware The voltage of protection circuit U5 reverse input ends will be above positive input reference voltage, the triode ON inside U5, test Level about 0.7V at point 1, voltage is 21V or so at test point 2, and effectively, oscillating circuit stops oscillation RST, top drive circuit No longer outputting drive voltage is incited somebody to action, so as to realize hardware insensitivity.R47 and C36 composition current waveform Spike-killers, can press down The leading peak edge of current waveform processed, strengthening system.（2）The power supply of NE555 connects+36V voltages, ground termination+21V voltages.NE555 and Peripheral circuit constitutes oscillating circuit, and the frequency of oscillation that oscillating circuit is produced is about 4-5kHz, and oscillator signal is defeated from 3 pin of NE555 After going out, output voltage lifting is arrived 50V or so by the voltage-multiplying circuit being made up of ceramic condenser C23 and C24, diode D3 and D4, It is sent to the grid of metal-oxide-semiconductor.The RST pin of NE555 can control the start-stop of oscillating circuit.The operation principle of voltage-multiplying circuit is：When 3 pin of NE555 are GND voltage（+21V）When, power supply 36V is charged by diode D4 to electric capacity C24, if time constant is closed Suitable, the voltage on C24 is approximately equal to 36V-21V=15V, and the right side is being born just in direction for left；When 3 pin of NE555 are high, electric capacity C24 is left Side is 36V, and right side is 36V+15V=51V, because the reverse-biased cut-offs of diode D4, the 51V voltages of generation are just given by diode D3 C23, C25 are charged, and so by the charging repeatedly in some cycles, the voltage on electric capacity C25 is just raised to required for rear portion drives 51V constant voltages.

In Figure 5, it is designed working-flow figure.Software section carries out modularization, systematization with high-level language And structured programming.The collection and treatment of signal are completed, two kinds of Working moulds of electronic and automatic cruising of electric bicycle are realized Formula and in the case of system fault with self-inspection work, and using digital PI control theories realize motor speed closed loop adjust System.

Claims (1)

1. a kind of BLDCM Drive System, it be by power circuit, micro control unit circuit, inverter driving circuit, Hardware braking protection circuit, vibration voltage-multiplying circuit, detection circuit, AVR single chip composition, it is characterised in that：AVR single chip is connected Power circuit, micro control unit circuit, inverter driving circuit, hardware braking protection circuit, vibration voltage-multiplying circuit, detection electricity Road.