CN102358391B

CN102358391B - Micro-power consumption electric bicycle controller

Info

Publication number: CN102358391B
Application number: CN201110202372.9A
Authority: CN
Inventors: 郁百超
Original assignee: Individual
Current assignee: Individual
Priority date: 2011-07-19
Filing date: 2011-07-19
Publication date: 2014-03-12
Anticipated expiration: 2031-07-19
Also published as: CN102358391A

Abstract

The invention discloses a micro-power consumption electric bicycle controller, which employs a variable-amplitude control method to regulate the speeds of a brushed direct current motor and a brushless direct current motor. The micro-power consumption electric bicycle controller is mainly characterized in that: all output power can be obtained by performing traditional power conversion on a small part of input power, namely actual power conversion is not required to be performed on the most part of the input power, a magnetic core transformer or inductor is not required to transfer the input power, and the input power directly reaches an output end to become the output power; the conversion efficiency can be 100 percent; pulse width modulation (PWM) is not performed on a main power component and electromagnetic interference (EMI) is not generated; the circuit is simple, so that the micro-power consumption electric bicycle controller is low in power consumption, long in service life, safe, reliable, energy-saving and environment-friendly; and the cost, the volume, the weight, and the power consumption of the micro-power consumption electric bicycle controller are 1/10 of those of the conventional electric bicycle controller.

Description

Micro-power consumption motor-assisted bicycle controller

Technical field

The utility model relates to a kind of micro-power consumption motor-assisted bicycle controller.

Background technology

Fig. 1 circuit is to have brushless motor controller, and its core is PWM pulse-width modulation, adopts control chip TL494, has comprised in addition storage battery under-voltage protection, over current of motor protection, brake power-off, electric weight demonstration etc.H is that high step-down type Hall speed is controlled handle, and by unclamping while screwing, its output can obtain the voltage of 4V-1V.This voltage is added to the 2. pin of TL494, compares with 1. pin voltage, at 8. pin, obtains widened pulse.2. pin voltage is lower, and 8. the low level part of the widened pulse of pin output is wider, and motor speed is higher, and potentiometer VR2 regulates for zero-speed, and while regulating VR2 that handle is unclamped, motor stalling is after a bit.36V input voltage is after KEY1, directly enter motor, when metal-oxide-semiconductor Q2 saturation conduction, motor has electric current to pass through to rotate, when Q2 ends, the additional 36V battery tension of motor is no longer powered, but the existence because of inductance L 1 and capacitor C 1, C2, C3, still has electric current to pass through in motor, motor still rotates, the speed of electric machine rotation is determined by the direct voltage by motor, and direct voltage is the pulse duration of being exported by Q2, determines.The degree of tightness of the handle Hall H of control rate has determined the pulsewidth of Q2 output voltage.

Fig. 2 circuit is Controller for PM DC Brushless Motor, and its core is also PWM pulse-width modulation, adopts control chip MC33035.Main process chip according to brushless electric machine motor suddenly the metal-oxide-semiconductor drive circuit on ear signal Dui Shang tri-road He Xia tri-tunnels provide and selectively open and close, complete motor commutation.Meanwhile, the carrier signal Yu Xia tri-road metal-oxide-semiconductor Continuity signals of the large young pathbreaker's corresponding pulses of the input voltage width suddenly claiming according to handle mix, to reach the object of controlling motor speed.The control of brushless electric machine has 2 hall devices, and motor Hall is controlled the commutation of direct voltage, and handle Hall is controlled motor speed.

The amplitude of output pulse is exactly the terminal voltage of the monolateral decline of storage battery, and during normal operation, metal-oxide-semiconductor IRF3205, within a commutation cycle, exports pulse train ripple, and the number of this impulse wave is determined frequently by work.Accumulator voltage is lower, or rate request is when higher, and output pulse is wider, duty ratio is larger, this is that voltage is higher because the rotating speed of direct current machine is determined by input direct voltage value, and speed is larger, when accumulator voltage drops to certain value, or speed is while bringing up to certain value, pulse duration, or duty ratio is 100%, output is direct voltage, is no longer pulse train ripple.

Conventional electric bicycle controller generally adopts Buck circuit topography, no matter there are brush or brshless DC motor, the method of speed governing is all the amplitude that regulates input direct voltage, in above-mentioned two kinds of controllers, the control of speed, it is the adjusting of direct voltage amplitude, to complete by changing the duty ratio of widened pulse square wave, its method of work is, first a kind of direct voltage of input is all become to high-frequency square wave, then use large capacitor filtering, become another kind of direct voltage, this method has following defect:

1) adopt the method for pulse-width modulation, the production process of high-frequency, high-power square wave, namely strong EMI disturbs the process producing, and DC converter is equivalent to a high frequency power transmitting station, can infer, and the interference producing is what serious.

2) in power conversion process, the whole of input power must carry out actual power conversion, and the power of all conversion must could arrive output by core transformers or inductance transmission, and loss is large, and efficiency is low.

Summary of the invention

First micro-power consumption motor-assisted bicycle controller controls a direct voltage stable, that amplitude is variable of position generation of handle according to Hall speed, then this direct voltage is directly introduced to motor.For there being brushless motor, with a DC switch, for brshless DC motor, adopt three-phase bridge switch, the switch here, is only switch, without high-frequency loss in all senses.Because within a commutation cycle, what switching tube IRF3205 exported is direct voltage forever, but not pulse train ripple.The circuit of a direct voltage stable, that amplitude is variable of this generation is exactly direct current amplitude transformer.

Fig. 3 is direct current amplitude transformer theory diagram, when input voltage is within rated range (being controlled the determining positions of handle by Hall speed), needn't carry out any power conversion, and input voltage directly arrives output, becomes output voltage.When input voltage is greater than rated voltage, through voltage cutting circuit, that part voltage that is greater than rated voltage is scaled off, carry out conventional power conversion, be transformed into the direct voltage of specified output, together with that left part direct voltage parallel output of cutting.When input voltage is less than rated voltage, through voltage compensating circuit, that part direct voltage that is less than rated voltage in input voltage is compensated, by compensating circuit, produce a bucking voltage, this voltage is the poor of rated voltage and input voltage just, be superimposed upon on input voltage, output voltage is input voltage and bucking voltage sum.

The amplitude of the direct voltage Vo of above-mentioned amplitude transformer output is according to Hall speed, to control the determining positions of handle, and the amplitude of Vo has determined the rotating speed of motor.Regulate the frequency converter of alternating current machine speed similar with adopting the method that changes input voltage frequency, adopt the method that changes input voltage amplitude to regulate motor speed herein, therefore claim amplitude transformer.

Micro-power consumption motor-assisted bicycle controller is comprised of direct current amplitude transformer, direct current amplitude transformer is comprised of field effect transistor Q1-Q4 and peripheral element, field effect transistor Q2, the drain electrode of Q3, with diode D1, the anode of D2, all be connected together with the different name end of inductance L 1, the negative electrode of diode D1 connects the Same Name of Ends of inductance L 1 by the drain-source utmost point of field effect transistor Q1, simultaneously by capacitor C 2 ground connection, the negative electrode of diode D2 connects the Same Name of Ends of inductance L 1 by capacitor C 1, simultaneously by the drain-source utmost point and capacitor C 3 ground connection of field effect transistor Q4, the source electrode of field effect transistor Q2 is by resistance R 1 ground connection, the source ground of field effect transistor Q3, driving signal V1-V4 is respectively the gate drive signal of field effect transistor Q1-Q4, and input voltage V5 is connected between the Same Name of Ends and ground of inductance L 1.

Accompanying drawing explanation

Fig. 1 tradition has brush direct current drive bicycle controller;

Fig. 2 conventional permanent magnet brushless direct current drive bicycle controller;

The micro-power consumption voltage of Fig. 3 bicycle controller theory diagram;

Fig. 4 direct-current voltage reducing circuit;

Each point voltage simulation waveform of Fig. 5 direct-current voltage reducing circuit;

Fig. 6 DC voltage booster circuit;

Each point voltage simulation waveform of Fig. 7 DC voltage booster circuit;

Fig. 8 amplitude transformer schematic circuit;

The micro-power consumption electric bicycle of Fig. 9 has brushless motor controller;

The micro-power consumption permanent-magnet brushless dc of Figure 10 controller;

Figure 11 battery discharging characteristic curve;

Fig. 4 voltage cutting circuit, V3 is the gate drive signal of N-type metal-oxide-semiconductor Q2, frequency 100KHz, Q1 is P type metal-oxide-semiconductor, and its gate drive signal V1 is identical with V3, and polarity is contrary, and V2=13.5V is input voltage, requires output voltage V o=15V.

When V3 is high level, Q2 saturation conduction, input direct voltage V2 is through 1 charging of 1 pair of inductance L of resistance R, linear the increasing of electric current on L1 stored electric energy, during this period simultaneously, the source voltage of Q2, output voltage V o is by gate drive signal clamper, and the voltage in inductance L 1 is determined by the pulsewidth of V2.

When V3 is low level, Q2 cut-off, charges to capacitor C 2 by diode D1 after the voltage stack in input voltage V2 and inductance L 1, and at the end, the voltage in capacitor C 2 is higher than input voltage V2 in charging.When next cycle arrives, the voltage in capacitor C 2 and input voltage V2 are through resistance R 1 jointly to inductance L 1 charging, and charging process is in aforementioned.1 couple of output voltage V o of capacitor C plays smoothing effect, because the source voltage of Q2 is followed the tracks of grid potential, so the amplitude of its gate drive signal is answered the high gate source voltage Vgs of specific output voltage Vo.

During metal-oxide-semiconductor Q2 saturation conduction, input voltage V2=13.5V, output voltage V o=12V, ignore Q2 tube voltage drop, the pressure drop in inductance L 1 should be a little more than 1.5V, between the metal-oxide-semiconductor Q2 off period, pressure drop polarity inversion on L1, with input voltage V2 stack (about 15V), voltage in capacitor C 1 is charged to and is greater than input voltage V2, because Q1, Q2 are synchronous, while starting to next cycle, voltage in capacitor C 1 charges to L1 by identical path with input voltage V2 simultaneously, produces output voltage V o on load resistance R1.Due to when the cycle starts, the voltage in capacitor C 1 is higher than input voltage V2, and the voltage in capacitor C 1 discharges by L1, Q2, R1 on the one hand, on the other hand to charge in batteries.Voltage on C1 discharges into lower than after input voltage V2, by V2, separately L1 is charged.

Said process goes round and begins again, during metal-oxide-semiconductor Q2 saturation conduction, be equivalent to the 12V in input voltage 13.5V to cut down as output voltage V o, between the metal-oxide-semiconductor Q2 off period, remaining 1.5V add input voltage 13.5V altogether 15V leave in capacitor C 1, when next cycle starts, leave 15V voltage in capacitor C 1 in together with input voltage, in to L1 charging, also on load resistance R1, form output voltage V o.In whole process, the 12V in 13.5V input voltage directly becomes power output, and the conversion efficiency of this partial power can be considered 100%, and residue 1.5V is transferred in capacitor C 1, regenerates or feeds back.

Metal-oxide-semiconductor Q2 gate drive signal is high frequency square wave, its source electrode is connected to load resistance R1 and the large capacitor C 2 of filtering, for high-frequency signal, the source electrode of Q2 is equivalent to ground connection, therefore the actual voltage that carries out or participate in PWM pulse-width modulation only only has 1.5V, and output voltage is 12V, directly confirmed " as long as the very small portion in input power is carried out to power conversion, just can obtain whole power outputs, be that exhausted major part in input power both needn't participate in actual power conversion, also needn't transmit by core transformers or inductance, directly arrive output, become power output ".Fig. 5 is the simulation waveform of each point voltage of voltage cutting circuit, from top to bottom successively: input voltage Vi, output voltage V o.

Fig. 6 is direct voltage compensating circuit, establishes input voltage Vi=10.5V, requires output voltage V o=12V, and this circuit produces a bucking voltage Vc=1.5V, is superimposed upon on input voltage, makes output voltage equal 12V.V2 is the gate drive signal of power MOS pipe Q2, is the square-wave signal of 100KHz, and V1 is input direct voltage.After circuit start, Q2 saturation conduction, cell voltage V1 charges to inductance L 1 by the drain-source utmost point of Q2, and inductive current is linear to be increased, and the energy storing in inductance is on the increase, and meanwhile, the voltage in capacitor C 2 discharges to load R2.After half period, Q2 cut-off, the electric energy being stored in inductance L 1 charges to capacitor C 1 by diode in the body of Q1.Voltage on C1 is superimposed upon on cell voltage V1, in load resistance R2 power supply, also to capacitor C 2 chargings.Fig. 7 is the simulation waveform of each point voltage, from top to bottom successively: output voltage V o, input voltage Vi, bucking voltage Vc.From figure, can see that output voltage V o (12V) is input voltage Vi (10.5V) and bucking voltage Vc (1.5V) sum.

Power MOS pipe Q1 does not drive signal, and that is that its saturation voltage drop is little, large by electric current because only utilize the forward characteristic of diode in power MOS pipe Q1 body.Fig. 7 is the simulation waveform of each point voltage, from top to bottom successively: output voltage V o, input voltage Vi, bucking voltage Vc.

Fig. 8 is amplitude transformer schematic circuit, power tube Q1, Q2, two are by pipe D1, inductance L 1, capacitor C 2, R1 the has formed reduction voltage circuit identical with Fig. 1, power tube Q3, Q4, inductance L 1, diode D2, capacitor C 1, C3 has formed booster circuit identical with Fig. 3, input voltage is added between the Same Name of Ends and ground of inductance L 1, and output voltage obtains at the source electrode of Q2, Q4.When input voltage is within rated value, only have Q2 each conducting of satisfying, input voltage is through the drain-source utmost point of inductance L 1 and metal-oxide-semiconductor Q2, directly output in resistance R 1; When input voltage is greater than rated value, Q3, Q4 cut-off, high input voltage can not arrive output end vo, after the step-down voltage of Q1, Q2 and peripheral element composition, at the source electrode output rated voltage of Q2; When input voltage is less than rated value, Q1, Q2 cut-off, Q4 saturation conduction, after the booster circuit consisting of, exports at end points Vo through the drain-source utmost point of Q4 Q3 and peripheral element.

Micro-power consumption buck converter that electric bicycle controller adopts, micro-power consumption booster converter is direct current amplitude transformer, its topmost feature is, exhausted most input power does not participate in actual power conversion, directly arrive output, become power output, the conversion efficiency of this exhausted most input power can be considered 100%, only have very small portion input power must carry out actual power conversion, this very small portion input power is carried out power conversion, the power loss producing is certainly very little, this very little power loss is converted into whole input voltage, and to carry out the power loss ratio of power conversion certainly less, thereby the efficiency of complete machine power conversion is very high.

Embodiment

Embodiment 1

Fig. 9 is the side circuit of micro-power consumption brush DC motors bicycle controller, compares with Fig. 1 brush DC motors controller:

1) after battery tension, increased the direct current amplitude transformer being formed by metal-oxide-semiconductor Q1-Q4, L1, D1, D2, C1, C2, C3,

2) input voltage of accessory power supply still connects storage battery.

3) handlebar Hall moves on to amplitude transformer the inside;

4) pin 1 of TL494 connects fixed voltage, and 8 output make-and-break signals of pin, control motor and walk to stop, and no longer bandwidth signals is adjusted in output;

5) terminal voltage of storage battery is no longer taken from the direct current supply of Q2 (IRF3205), but takes from the output dc voltage Vo of amplitude transformer.

Embodiment 2

Figure 10 is the side circuit of micro-power consumption brushless, permanently excited direct current motor bicycle controller, compares with Fig. 2 brushless motor controller:

2) input voltage of power supply chip 7815 still connects storage battery.

3) handlebar Hall moves on to amplitude transformer the inside;

4) pin 14 of MC33035 connects fixed voltage, and the commutation control signal that 14,2,1 and 19,20,21 output motor Halls of pin produce no longer produces and adjusts bandwidth signals;

5) terminal voltage of storage battery is no longer taken from the direct current supply of 6 IRF3205, but takes from the output dc voltage Vo of amplitude transformer.

Figure 11 is battery discharging characteristic curve, and in the discharge process of 0.2C, accumulator voltage changes between 12.7V at 11.3V, requires now the output voltage stabilization of 4 joint storage battery series connection at 48V.

1) when input voltage is greater than rated voltage, voltage cutting circuit start, storage battery ceiling voltage is 50.8V, input voltage is than high (the 50.8-48)/48=5.83% of rated voltage, what in input voltage Vi, exceed 5.83% is scaled off by clipper circuit, this part scaling off will be carried out power conversion, is transformed into rated value Voltage-output.If conversion efficiency is 90%, establishes and scale off the power loss Pq of this part voltage in carrying out power conversion process:

2)Pq＝5.83％*(1-90％)＝0.0583*0.1＝0.00583＝0.583％，

3) hence one can see that, and scaling off this part voltage loss in power conversion process is 0.583%.Very big part voltage after input voltage is cut, its amplitude equals rated voltage, directly arrive output, this a part of voltage itself is not through any power conversion, its conversion efficiency can be considered 100%, so the total losses of whole voltage cutting circuit are also 0.583%, its gross efficiency is 99.417%.

4) when input voltage is less than rated voltage, voltage cutting circuit start, storage battery minimum voltage is 45.6V, input voltage is than low (the 48-45.6)/48=5.00% of rated voltage, in input voltage Vi specific output voltage low go out 5.00% by compensating circuit, compensated, the acquisition of bucking voltage will be carried out power conversion, and establishing conversion efficiency is 90%, the power loss Pb in the power conversion process that acquisition bucking voltage is carried out:

5)Pb＝5.00％*(1-90％)＝0.05*0.1＝0.005＝0.5％，

6) hence one can see that, by obtaining bucking voltage, undertaken in power conversion process, and loss is 0.5%.This does not have input voltage Vi through any power conversion in voltage compensation process, directly from input, arrive output, become the most of power output, its conversion efficiency can be considered 100%, so the total losses of whole voltage cutting circuit are also 0.5%, its gross efficiency is 99.5%.

7) when input voltage is within rated range, the grid of power MOS pipe Q1 (please refer to Fig. 6) in voltage cutting circuit adds high-level control signal, Q1 is a DC switch, and input direct voltage Vi directly arrives output, and overall efficiency can be considered 100%.

8) with respect to three kinds of different operational modes, there are three kinds of different efficiency, 99.417%, 99.5%, 100%, because micro-power consumption direct-current voltage stabilizer is a moment, only have a kind of operational mode, the efficiency in above-mentioned three kinds of patterns is all overall efficiency, and this just means, operate under different mode, overall efficiency is different.If averaged, overall efficiency is 99.652%.

9), in the efficiency calculation process of voltage cutting and voltage compensation, be all the data while adopting worst case, i.e. ceiling voltage 50.8V and minimum voltage 45.6V.From the battery discharging characteristic curve of Fig. 7, can find out, the discharge time of ceiling voltage and minimum voltage is very short, long discharge time or at steady discharge range, do not get the data of worst case, and it is more reasonable to get median data during computational efficiency.While getting median data, the maximum discharge voltage of discharge voltage value is: (50.8-48)/2+48=1.4+48=49.4V, minimum discharge voltage is: 48-(48-45.6)/2=48-1.2=46.8, by the result that these data are calculated by the computational methods of above-mentioned efficiency, be: Pq=0.0292, Pb=0.025, so when starting resistor cuts, overall efficiency is 99.708%, during starting resistor compensation, overall efficiency is 99.775%.

10) amplitude transformer main circuit does not adopt PWM conversion, but utilizes the method for voltage cutting and voltage compensation, and stable DC voltage, is a large characteristic of micro-power consumption motor-assisted bicycle controller.Although the fluctuation range of input voltage Vi is positive and negative 5.417%, but the discharge voltage of storage battery is the longest in the time of 12.35V-11.7V (single battery), it is the longest to be that overall efficiency approaches time of 100%, so in actual motion, overall efficiency is 99.417% more much higher than above-mentioned estimation, approaches very much 100%.

It is according to Hall speed, to control the determining positions of handle that the galvanic current that amplitude transformer produces is pressed the amplitude of Vo, the amplitude of Vo has determined the rotating speed of motor, press Vo to introduce the DC switch of motor amplitude transformer galvanic current in good time, be 6 metal-oxide-semiconductor IRF3205 in Fig. 8, it is no longer the output device of widened pulse, no longer include the high-frequency loss of going up in all senses, power loss only only has saturation voltage drop, as adopt metal-oxide-semiconductor IRFP4004 to make DC switch, its saturated drain-source resistance is 1.7 milliohms only, by 20A electric current, pressure drop 0.034V, for 36V accumulator voltage, its actual power dissipation is 9/10000ths.

The amplitude of the stable DC voltage Vo of amplitude transformer output, is controlled the determining positions of handle, and has nothing to do with the terminal voltage of storage battery by Hall speed, when accumulator voltage drops to 33V by 42V is monolateral, the output voltage V o of amplitude transformer still can keep rated value constant.Electric bicycle adopts after amplitude transformer, and its speed is only relevant with the limit speed of motor, and irrelevant to accumulator voltage.

Amplitude transformer is applicable to the speed regulating control such as all brush DC motors, brushless, permanently excited direct current motor (BDCM), switched reluctance motor (SR), Doubly salient permanent magnet motor (DSPM), exempts storage battery voltage pre regulator simultaneously.

Claims

1. a micro-power consumption motor-assisted bicycle controller, it is characterized in that: micro-power consumption motor-assisted bicycle controller is comprised of direct current amplitude transformer, direct current amplitude transformer is comprised of field effect transistor Q1-Q4 and peripheral element, field effect transistor Q2, the drain electrode of Q3, with diode D1, the anode of D2, all be connected together with the different name end of inductance L 1, the negative electrode of diode D1 connects the Same Name of Ends of inductance L 1 by the drain-source utmost point of field effect transistor Q1, simultaneously by capacitor C 2 ground connection, the negative electrode of diode D2 connects the Same Name of Ends of inductance L 1 by capacitor C 1, simultaneously by the drain-source utmost point and capacitor C 3 ground connection of field effect transistor Q4, the source electrode of field effect transistor Q2 is by resistance R 1 ground connection, the source ground of field effect transistor Q3, driving signal V1-V4 is respectively the gate drive signal of field effect transistor Q1-Q4, and input voltage V5 is connected between the Same Name of Ends and ground of inductance L 1.