CN101404449B - Voltage converter and voltage conversion control method - Google Patents

Abstract

The invention relates to a voltage changing device and a method for executing a voltage changing control to the voltage changing device. A controller (30) calculates voltage instruction value of a booster converter (12) based on torque instruction value (TR1 (or TR2)) and motor revolution number (MRN1 (or MRN2)) and calculates duty ratio (D_ON_1) of an NPN transistor (Q1) based on calculated voltage instruction value and DC voltage (Vb) of the voltage sensor (10). Under the condition that the duty ratio (D_ON_1) is influenced by dead zone time and the DC voltage (Vb) is less than predetermined value, the controller (30) controls NPN transistor (Q1, Q2) for increasing or reducing the voltage when the duty ratio (D_ON_1) is fixed to 1.0.

Description

Voltage conversion device and execution are to the method for the voltage transformation control of voltage conversion device

The cross reference of related application

This non-provisional application is based on the Japanese patent application 2004-346991 and the 2005-075624 that submit to Japan Patent office respectively on November 30th, 2004 and on March 16th, 2005, and its full content is incorporated herein by reference.

Technical field

The present invention relates to a kind of voltage conversion device and a kind of execution method to the voltage transformation control of voltage conversion device.

Background technology

Recently, as the environment-friendly type vehicle, hybrid vehicle and electric motor car have caused extensive interest.Except conventional engine, the motor that hybrid vehicle also has DC (direct current) power supply, inverter and driven by described inverter is with as its power source.More specifically, described engine is actuated to provide power source, and, be transformed to AC (alternating current) voltage that is used to rotate described motor from the dc voltage of described DC power supply by described inverter, thereby power source is provided.

Electric motor car refers to have the DC power supply, inverter and the motor that driven by described inverter be as the vehicle of its power source.

Consider this hybrid vehicle or electric motor car, and worked out such structure, therein, utilize booster converter that the dc voltage from described DC power supply is boosted, and the dc voltage after boosting is provided for the described inverter (for example, referring to open 08-214592 of Japan Patent and 2005-051895) of drive motors.

Described booster converter is included in two NPN transistor that are connected in series between the power line of described inverter and the ground wire, and an end is connected with intermediate point between described two NPN transistor and reactor that the other end is connected with the power line of described power supply.

Described booster converter is with predetermined duty ratio unlatching/shutoff described NPN transistor (upper arm) that is connected with described power line and the described NPN transistor (underarm) that is connected with described ground wire, thereby the dc voltage from described power supply is boosted, and the voltage after will boosting offers described inverter, and the dc voltage from described inverter is carried out step-down so that the voltage after the step-down is offered described power supply.

Because described upper arm and described underarm as the assembly of described booster converter are connected in series between described power line and described ground wire, need avoid described upper arm and described underarm to open simultaneously.Therefore, the control signal for the switching that is used to control described upper arm and described underarm provides Dead Time to open simultaneously to avoid described upper arm and described underarm.

Figure 28 is the time diagram of the control signal of described upper arm of control and described underarm.

With reference to Figure 28, in each control cycle T, described upper arm and described underarm are by the duty ratio unlatching/shutoff to be scheduled to.Described underarm is held open up to moment t1, and described upper arm keeps turn-offing up to moment t1.If at moment t1, described upper arm is opened subsequently and described underarm turn-offs subsequently, and then described upper arm and described underarm may be opened simultaneously.Therefore, described underarm turn-offs at moment t1, and described upper arm is opened at moment t2, and one section Dead Time is arranged from moment t1 to moment t2.

Yet if the voltage instruction value of described booster converter and supply voltage are quite approaching, the duty ratio of described upper arm (refer to described upper arm be held open during) is quite high, for example, and 0.98.In this case, the part of duty ratio 0.98 is occupied by described Dead Time or is taken, thereby can not guarantee the time that described upper arm should be held open.In other words, very near 1.0 zone, one section dead zone appears in described duty ratio, therein because described Dead Time and can not guarantee any duty ratio.

Figure 29 A and 29B are respectively the voltage of described upper arm and the time diagram of duty ratio.

With reference to Figure 29 A, suppose that the supply voltage Vb that boosts starts working at moment t0, described voltage instruction value increases from supply voltage Vb.During from moment t0 to moment t1, described voltage instruction value is very near supply voltage Vb.Therefore, the duty ratio of the described upper arm that calculates based on described voltage instruction value is partly taken by the Dead Time of described upper arm, thereby can not guarantee initial duty cycle.So in 1.0 to 0.95 scope for example, the duty ratio of described upper arm can not be controlled linearly, thus vibration (referring to Figure 29 B).Therefore, the output voltage of described booster converter also vibrate (referring to Figure 29 A).

Along with the duty ratio of the described upper arm that calculates based on described voltage instruction value for example reaches 0.95, described duty ratio is no longer partly taken by described Dead Time, and described duty ratio can be controlled linearly.

Therefore when described voltage instruction value had been in close proximity in the zone of supply voltage Vb, the duty ratio of described upper arm was partly taken by described Dead Time, the output voltage vibration of described booster converter, and also vibrate from the DC electric current of described power supply.So described power supply may be damaged.

In addition, carry out boost operations during, when the duty ratio of described upper arm during, can not guarantee described initial duty cycle, and in the moment that stops described boost operations, described duty ratio becomes 1.0 suddenly in above-mentioned dead zone.At this moment, because described duty ratio flip-flop, the output voltage of described booster converter is also reduced to supply voltage Vb suddenly.Therefore, the DC electric current from described power supply increases suddenly.So, because excessive DC electric current flows through, the described power supply that can on performance, detract, and therefore shorten its useful life.

Summary of the invention

One object of the present invention is to provide a kind of voltage conversion device, and it can reduce the output voltage vibration.

Another object of the present invention is to provide a kind of method of carrying out voltage transformation control, reduces the vibration of output voltage thus.

According to the present invention, a kind of voltage conversion device that changes changeably the input voltage of inverter comprises: voltage changer, and it comprises upper arm and underarm, and carries out voltage transformation between power supply and described inverter by the switching of described upper arm and underarm; And control device, it controls described voltage changer, thereby reduces the influence of the Dead Time of described voltage changer to the duty ratio of described switching.

Preferably, when the voltage instruction value of described voltage transformation greater than supply voltage less than predetermined voltage and described supply voltage during less than the predetermined set value, described control device is set to be used to indicate the duty that stops described voltage transformation recently to control described voltage changer by described duty ratio.

Preferably, when described voltage instruction value was at least described predetermined set value greater than described supply voltage less than described predetermined voltage and described supply voltage, described control device was set to be used to indicate the duty that carries out described voltage transformation recently to control described voltage changer by described duty ratio.

Preferably, based on the permission maximum voltage of described power supply, the DC current maxima of described power supply and the internal resistance of described power supply when described voltage changer carries out the transition to the state that stops described voltage transformation, described predetermined set value is set.

Preferably, described internal resistance is set to the maximum of the internal resistance of described power supply employing.

Preferably, described internal resistance is set to the measured value of described internal resistance.

Preferably, the temperature based on described power supply is provided with described internal resistance.

Preferably, based on the detected value of the output voltage of described voltage changer and the detected value of described supply voltage described DC current maxima is set.

According to the present invention, a kind of voltage conversion device that changes changeably the input voltage of inverter comprises: voltage changer, it comprise in each cycle with the first duty ratio time corresponding section in the upper arm that is unlocked, and in each cycle with the second duty ratio time corresponding section in the underarm that is unlocked, and carry out voltage transformation between power supply and described inverter by the switching of described upper arm and described underarm, wherein, described second duty ratio equals to deduct the value that described first duty ratio obtains from 1; And control device, described first duty ratio of calculating when the voltage instruction value based on the described voltage transformation that is undertaken by described voltage changer is influenced by the Dead Time of described upper arm and described underarm, and when supply voltage was influenced by described Dead Time, it recently controlled the switching of described upper arm and described underarm by described first duty is set.

Preferably, when described first duty ratio of calculating based on described voltage instruction value greater than maximum effective duty ratio and less than the longest duty ratio that in control cycle is long, keeps described upper arm unlatching, and when described supply voltage was at least the predetermined set value, described control device was set to the switching that the effective duty of described maximum is recently controlled described upper arm and described underarm by described first duty ratio.By determining the effective duty ratio of described maximum divided by described control cycle length, wherein, determine that by from described control cycle is long, deducting described Dead Time described effective control cycle is long with effective control cycle length.The product of the DC current maxima of the described power supply of the internal resistance by deducting described power supply from the permission maximum voltage of described power supply when being switched to described the longest duty ratio when described first duty ratio is determined described predetermined set value.

Preferably, when described first duty ratio of calculating based on described voltage instruction value greater than the effective duty ratio of described maximum and less than the longest described duty ratio that in described control cycle is long, keeps described upper arm unlatching, and described supply voltage is during less than described predetermined set value, and described control device is set to the switching that the longest described duty is recently controlled described upper arm and described underarm by described first duty ratio.

Preferably, the voltage instruction value of the described voltage transformation that is undertaken by described voltage changer greater than the situation of supply voltage less than predetermined voltage under, described control device is recently controlled described voltage changer by utilizing first duty ratio and second duty ratio that described duty is set, wherein, described first duty ratio is the duty ratio when the voltage of described predetermined voltage is at least described voltage instruction value, and described second duty ratio is the duty ratio when described supply voltage is described voltage instruction value.

Preferably, may produce under the situation of surge (surge) at the DC of described power supply electric current, described control device is recently controlled described voltage changer by utilizing first duty ratio and second duty ratio that described duty is set, wherein, described first duty ratio is the duty ratio when the voltage of predetermined voltage is at least voltage instruction value, and described second duty ratio is the duty ratio when supply voltage is described voltage instruction value.

Preferably, described control device is by being provided with described duty ratio with predetermined than switching between described first duty ratio and described second duty ratio.

According to the present invention, a kind of voltage conversion device that changes changeably the input voltage of inverter comprises: voltage changer, it comprise in each cycle with the first duty ratio time corresponding section in the upper arm that is unlocked, and in each cycle with the second duty ratio time corresponding section in the underarm that is unlocked, and carry out voltage transformation between power supply and described inverter by the switching of described upper arm and described underarm, wherein, described second duty ratio equals to deduct the value that described first duty ratio obtains from 1; And control device, when described first duty ratio of calculating based on the voltage instruction value of the described voltage transformation that is undertaken by described voltage changer influence by the Dead Time of described upper arm and described underarm, it was set to switch the switching of controlling described upper arm and described underarm between the longest duty ratio of effective duty ratio of maximum and the described upper arm unlatching of maintenance in control cycle is long by described first duty ratio.By determining the effective duty ratio of described maximum divided by described control cycle length, wherein, determine that by from described control cycle is long, deducting described Dead Time described effective control cycle is long with effective control cycle length.

Preferably, when the voltage instruction value of the described voltage transformation that is undertaken by described voltage changer during greater than supply voltage and less than predetermined voltage, described control device is controlled described voltage changer by changing the carrier frequency of the switching of controlling described upper arm and described underarm.

Preferably, reduce the control of the described output voltage of the control of output voltage of described voltage changer or the described voltage changer that raises when described control device, and described voltage instruction value is during greater than described supply voltage and less than described predetermined voltage, and described control device changes described carrier frequency.

Preferably, when described control device reduces the control of the output voltage of described voltage changer, and described voltage instruction value is during greater than described supply voltage and less than described predetermined voltage, and described control device changes described carrier frequency.

Preferably, determine described predetermined voltage based on the described Dead Time of described voltage changer.

According to the present invention, a kind of voltage conversion device that changes changeably the input voltage of inverter comprises: voltage changer, it comprise in each cycle with the first duty ratio time corresponding section in the upper arm that is unlocked, and in each cycle with the second duty ratio time corresponding section in the underarm that is unlocked, and carry out voltage transformation between power supply and described inverter by the switching of described upper arm and described underarm, wherein, described second duty ratio equals to deduct the value that described first duty ratio obtains from 1; And control device, when described first duty ratio of calculating based on the voltage instruction value of the described voltage transformation that is undertaken by described voltage changer is influenced by the Dead Time of described upper arm and described underarm, it controls the switching of described upper arm and described underarm according to the increase of described first duty ratio by the carrier frequency that changes the switching of controlling described upper arm and described underarm.

Preferably, described control device is in the scheduled period when described voltage transformation begins and carrying out the transition in scheduled period of the state that described voltage transformation is stopped and change described carrier frequency.

According to the present invention, provide the method for a kind of execution to the voltage transformation control of voltage conversion device.Described voltage conversion device has voltage changer, it comprise in each cycle with the first duty ratio time corresponding section in the upper arm that is unlocked, and in each cycle with the second duty ratio time corresponding section in the underarm that is unlocked, and carry out voltage transformation between power supply and described inverter by the switching of described upper arm and described underarm, wherein, described second duty ratio equals to deduct the value that described first duty ratio obtains from 1.Described method comprises: the first step, calculate described first duty ratio based on the voltage instruction value of described voltage transformation; In second step, determine whether described first duty ratio that calculates is influenced by the Dead Time of described upper arm and described underarm; In the 3rd step, when definite described first duty ratio that calculates is influenced by described Dead Time, determine whether supply voltage is influenced by described Dead Time; And the 4th the step, when definite described supply voltage is influenced by described Dead Time, recently control the switching of described upper arm and described underarm by described first duty is set.

Preferably, described second step comprises: first substep, utilize described Dead Time to calculate maximum effectively duty ratio; Second substep determines that whether described first duty ratio that calculates is greater than the effective duty ratio of described maximum and less than the longest duty ratio that keeps described upper arm to open in control cycle is long; The 3rd substep when described first duty ratio during greater than the effective duty ratio of described maximum and less than described the longest duty ratio, determines that described first duty ratio is influenced by described Dead Time; And the 4th substep, when described first duty ratio is at most the effective duty ratio of described maximum or during for described the longest duty ratio, determines that described first duty ratio is not influenced by described Dead Time.By determining the effective duty ratio of described maximum divided by described control cycle length, wherein, determine that by from described control cycle is long, deducting described Dead Time described effective control cycle is long with effective control cycle length.

Preferably, described the 3rd step comprises: the 5th substep, determine that whether described supply voltage is less than the predetermined set value; The 6th substep when described supply voltage is at least described predetermined set value, determines that described supply voltage is influenced by described Dead Time; And the 7th substep, when described supply voltage during, determine that described supply voltage is not influenced by described Dead Time less than described predetermined set value.The product of the DC current maxima of the described power supply of the internal resistance by deducting described power supply from the permission maximum voltage of described power supply when being switched to described the longest duty ratio when described first duty ratio is determined described predetermined set value.

Preferably, when definite described supply voltage was influenced by described Dead Time, described the 4th step was set to the switching that the effective duty of described maximum is recently controlled described upper arm and described underarm by described first duty ratio.

Preferably, when determining that described supply voltage is not influenced by described Dead Time, carry out the 5th step, be set to the switching that the longest described duty is recently controlled described upper arm and underarm by described first duty ratio.

According to the present invention, provide the method for a kind of execution to the voltage transformation control of voltage conversion device.Described voltage conversion device has voltage changer, it comprise in each cycle with the first duty ratio time corresponding section in the upper arm that is unlocked, and in each cycle with the second duty ratio time corresponding section in the underarm that is unlocked, and carry out voltage transformation between power supply and described inverter by the switching of described upper arm and described underarm, wherein, described second duty ratio equals to deduct the value that described first duty ratio obtains from 1.Described method comprises: the first step, calculate described first duty ratio based on the voltage instruction value of described voltage transformation; In second step, determine whether described first duty ratio that calculates is influenced by the Dead Time of described upper arm and described underarm; And the 3rd the step, when definite described first duty ratio is influenced by described Dead Time, the switching that described first duty is recently controlled described upper arm and described underarm is set by the longest duty ratio of utilizing maximum effectively duty ratio and in control cycle is long, keep described upper arm to open.

Preferably, described second step comprises: first substep, utilize described Dead Time to calculate the effective duty ratio of described maximum; Second substep determines that whether described first duty ratio that calculates is greater than the effective duty ratio of described maximum and less than the longest described duty ratio that keeps described upper arm to open in described control cycle is long; The 3rd substep when described first duty ratio during greater than the effective duty ratio of described maximum and less than described the longest duty ratio, determines that described first duty ratio is influenced by described Dead Time; And the 4th substep, when described first duty ratio is at most the effective duty ratio of described maximum or during for described the longest duty ratio, determines that described first duty ratio is not influenced by described Dead Time.By determining the effective duty ratio of described maximum divided by described control cycle length, wherein, determine that by from described control cycle is long, deducting described Dead Time described effective control cycle is long with effective control cycle length.

Preferably, described second step comprises: first substep, detect the DC electric current of described power supply; Second substep, whether the slope of output waveform of DC electric current of described detection of determining described power supply is greater than predetermined threshold; The 3rd substep when the described slope of the described output waveform of the described DC electric current of described power supply during greater than described predetermined threshold, determines that described first duty ratio is influenced by described Dead Time; And the 4th substep, when the described slope of the described output waveform of the described DC electric current of described power supply is at most described predetermined threshold, determine that described first duty ratio is not influenced by described Dead Time.

Preferably, described the 3rd step is by being provided with described first duty ratio with predetermined than switching between effective duty ratio of described maximum and the longest described duty ratio.

According to the present invention, provide the method for a kind of execution to the voltage transformation control of voltage conversion device.Described voltage conversion device has voltage changer, it comprise in each cycle with the first duty ratio time corresponding section in the upper arm that is unlocked, and in each cycle with the second duty ratio time corresponding section in the underarm that is unlocked, and carry out voltage transformation between power supply and described inverter by the switching of described upper arm and described underarm, wherein, described second duty ratio equals to deduct the value that described first duty ratio obtains from 1.Described method comprises: the first step, calculate described first duty ratio based on the voltage instruction value of described voltage transformation; In second step, determine whether described first duty ratio that calculates is influenced by the Dead Time of described upper arm and described underarm; And the 3rd step, when definite described first duty ratio that calculates influence by described Dead Time, the carrier frequency of controlling the switching of described upper arm and described underarm by change was controlled the switching of described upper arm and described underarm.

Preferably, described second step comprises: first substep determines whether the output voltage of described voltage changer is carried out the step-down control or the control of boosting; Second substep when the described output voltage to described voltage changer carries out step-down control, determines that described first duty ratio is influenced by described Dead Time; And the 3rd substep, when the described output voltage to described voltage changer boosts control, determine that described first duty ratio is not influenced by described Dead Time.

Preferably, described the 3rd step changes described carrier frequency according to the increase of described first duty ratio.

Preferably, in described the 3rd scheduled period of step when described voltage transformation begins and carrying out the transition in scheduled period of the state that described voltage transformation is stopped and change described carrier frequency.

When the described voltage instruction value of described voltage transformation is at least described supply voltage, when being at most predetermined voltage and described supply voltage and being at least the predetermined set value, the described duty ratio of described voltage conversion device of the present invention is set to be used to indicate the duty ratio of carrying out voltage transformation.

Therefore, because described voltage changer does not carry out the transition to the state that described voltage transformation is stopped, so the variation in the described supply voltage is reduced.

Described voltage instruction value at described power conversion is at least described supply voltage, when being at most predetermined voltage, described voltage conversion device of the present invention utilizes described first duty ratio and described second duty ratio that described duty ratio is set, wherein, described first duty ratio is the duty ratio when the voltage of predetermined voltage is at least voltage instruction value, and described second duty ratio is the duty ratio when supply voltage is described voltage instruction value.

Therefore, described duty ratio is not controlled by the influence of described Dead Time can linearly, and can be alleviated from the described DC current oscillation of described power supply.

When the described power supply command value of described voltage transformation is at least described supply voltage, when being at most predetermined voltage, described voltage conversion device of the present invention is controlled described voltage changer by the carrier frequency that changes the described switching of control.

Therefore, can reduce by described Dead Time cause based on the duty ratio of voltage instruction value and the difference between the actual duty cycle, and also can reduce the variation of output voltage of described voltage changer and the variation of DC electric current.

According to the present invention, can reduce the output voltage of described voltage changer and from the vibration of the described DC electric current of described power supply.Therefore, can avoid described power supply to be damaged.

From following with reference to accompanying drawing to the specific descriptions of the present invention, above and other purpose, characteristics, aspect and advantage of the present invention will become more obvious.

Description of drawings

Fig. 1 is the theory diagram of motor driving apparatus, and this equipment has the voltage conversion device according to first embodiment of the invention;

Fig. 2 is the functional block diagram of the control device shown in Fig. 1;

Fig. 3 is the functional block diagram of the controller for transducer shown in Fig. 2;

Fig. 4 shows the relation between duty ratio D_ON_1 and the voltage instruction value Vdc_com;

Fig. 5 A and 5B are respectively the voltage of NPN transistor Q1 (upper arm) and the time diagram of duty ratio D_ON_1;

Fig. 6 is a flow chart, and it has illustrated the operation of the voltage transformation of the controller for transducer control booster converter among Fig. 3;

Fig. 7 is the functional block diagram according to the controller for transducer of the motor driving apparatus of first modified example of first embodiment of the invention;

Fig. 8 is the functional block diagram according to the controller for transducer of the motor driving apparatus of second modified example of first embodiment of the invention;

Fig. 9 is the functional block diagram according to the controller for transducer of the motor driving apparatus of second embodiment of the invention;

Figure 10 shows the relation between duty ratio D_ON_1 and the voltage instruction value Vdc_com;

Figure 11 is based on the time diagram of predetermined ratio CR by the signal PWMU of converter pwm signal converter unit generation;

Figure 12 A and 12B are respectively the voltage of NPN transistor Q1 (upper arm) and the time diagram of duty ratio D_ON_1;

Figure 13 is a flow chart, and it has illustrated the operation of the voltage transformation of controller for transducer control booster converter;

Figure 14 is the theory diagram of described motor driving apparatus, and this motor driving apparatus has the voltage conversion device according to first modified example of second embodiment of the invention;

Figure 15 is the functional block diagram of controller for transducer, and this controller for transducer is contained in the control device among Figure 14;

Figure 16 is a flow chart, and it has illustrated the operation of the voltage transformation of described controller for transducer control booster converter;

Figure 17 shows the relation between duty ratio D_ON_1 and the actual duty cycle;

Figure 18 is the functional block diagram according to the controller for transducer of the motor driving apparatus of third embodiment of the invention;

Figure 19 shows the relation between duty ratio D_ON_1 and the carrier frequency fc;

Figure 20 is a flow chart, and it has illustrated the operation of the converter pwm signal converter unit 54D control carrier frequency fc of the controller for transducer that utilizes among Figure 18;

Figure 21 show according to third embodiment of the invention based on the duty ratio D_ON_1 of voltage transformation and the relation between the actual duty cycle;

Figure 22 is the functional block diagram according to the controller for transducer of the motor driving apparatus of first modified example of third embodiment of the invention;

Figure 23 is a time diagram, and it shows the relation between pressure-increasning state command signal B_com and the carrier frequency fc;

Figure 24 is a flow chart, and it has illustrated the operation of the converter pwm signal converter unit control carrier frequency fc of the controller for transducer that utilizes among Figure 22;

Figure 25 is the functional block diagram according to the controller for transducer of the motor driving apparatus of second modified example of third embodiment of the invention;

Figure 26 is a flow chart, and it has illustrated the operation of the converter pwm signal converter unit 54F control carrier frequency fc of the controller for transducer that utilizes among Figure 25;

Figure 27 show according to second modified example of third embodiment of the invention based on the duty ratio D_ON_1 of voltage transformation and the relation between the actual duty cycle;

Figure 28 is the time diagram that is used to control the control signal of upper arm and underarm;

Figure 29 A and 29B are respectively the voltage of described upper arm and the time diagram of duty ratio.

Embodiment

Describe embodiments of the invention in detail hereinafter with reference to accompanying drawing.In the accompanying drawings, similar assembly marks with similar reference character.

First embodiment

Fig. 1 is the theory diagram of motor driving apparatus, and this motor driving apparatus has the voltage conversion device according to first embodiment of the invention.

With reference to Fig. 1, motor driving apparatus 100 comprises DC power supply B, voltage sensor 10,20, system relay SR1, SR2, capacitor 11,13, booster converter 12, inverter 14,31, current sensor 24,28, and control device 30.

Motor generator MG1 for example is installed on the hybrid vehicle.Motor generator MG1 is connected with the engine (not shown) of described hybrid vehicle, serving as by described engine-driven power generator, and can also serve as the motor that for example can start the described engine of described engine.Control by the power generation torque of adjusting motor generator MG1, thereby described engine is remained on effective operating state.So, can realize the good conservation of fuel and the toxic emission of described hybrid vehicle.

Motor generator MG2 for example is installed on the hybrid vehicle.Motor generator MG2 is a drive motors, thereby it is used to produce the driving wheel that moment of torsion also drives described hybrid vehicle.In addition, the situation of described vehicle deceleration, motor generator MG2 is rotated in the rotation of described driving wheel, and motor generator MG2 can serve as power generator (function that is called regenerative electric power).

Booster converter 12 comprises reactor L1, NPN transistor Q1, Q2 and diode D1, D2.The end of reactor L1 is connected to the power line of DC power supply B, and the other end is connected to the intermediate point between NPN transistor Q1 and the Q2, that is, be connected between the collector electrode of the emitter of NPN transistor Q1 and NPN transistor Q2.NPN transistor Q1, Q2 are connected in series between power line and ground wire.The collector electrode of NPN transistor Q1 is connected with described power line, and the emitter of NPN transistor Q2 is connected with described ground wire.At separately between the collector and emitter of NPN transistor Q1, Q2, connected and be used for from diode D1, the D2 of each emitter to each collector electrode streaming current.

Inverter 14 comprises U phase arm 15, V phase arm 16 and W arm 17 mutually.U phase arm 15, V phase arm 16 and W phase arm 17 are connected in parallel between described power line and described ground wire.

U phase arm 15 comprises NPN transistor Q3, the Q4 that is connected in series, and V phase arm 16 comprises NPN transistor Q5, the Q6 that is connected in series, and W phase arm 17 comprises NPN transistor Q7, the Q8 that is connected in series.At separately between the collector and emitter of NPN transistor Q3-Q8, connected and be used for from the diode D3-D8 of each emitter to each collector electrode streaming current.

The intermediate point of each phase arm is connected with an end of the phase coil of motor generator MG1.Particularly, motor generator MG1 is a three-phase motor with permanent magnets, and it disposes U, V and W three coils mutually.One end of one end of U phase coil, an end of V phase coil and W phase coil is connected at public intermediate connection point, and the other end of described U phase coil is connected with intermediate point between NPN transistor Q3, the Q4, the other end of described V phase coil is connected with intermediate point between NPN transistor Q5, the Q6, and the other end of described W phase coil is connected with intermediate point between NPN transistor Q7, the Q8.

It is identical with inverter 14 that inverter 31 is configured to.

DC power supply B comprises secondary or rechargeable battery, for example, and Ni-MH battery or lithium battery.Voltage sensor 10 detects from the dc voltage Vb (being also referred to as " cell voltage Vb ") of DC power supply B output, exports to control device 30 with the dc voltage Vb with described detection.

System relay SR1, SR2 are in response to the signal SE On/Off from control device 30.

The dc voltage Vb that capacitor 11 smoothly provides from described DC power supply B is with the dc voltage Vb provide smoothly to booster converter 12 after.

12 couples of described dc voltage Vb from capacitor 11 of booster converter boost, and offer capacitor 13 with the voltage after will boosting.More specifically, receive signal PWMU from control device 30, booster converter 12 in response to signal PWMU according to NPN transistor open during, the described dc voltage Vb that raises, and the voltage of described rising offered capacitor 13.

In addition, receive the signal PWMD from control device 30,12 pairs of booster converters carry out step-down via capacitor 13 from the dc voltage that inverter 14 and/or inverter 31 provide, so that DC power supply B is charged.

Capacitor 13 level and smooth dc voltages from booster converter 12, and the dc voltage after inciting somebody to action smoothly via node N1, N2 offers inverter 14,31.Voltage sensor 20 detects the end-to-end voltage of capacitors 13, that is, the output voltage V m of booster converter 12 (corresponding to the input voltage of inverter 14,31, below as the same) outputs to control device 30 with the output voltage V m with described detection.

The described dc voltage that reception provides from capacitor 13, inverter 14 is transformed to AC voltage based on the signal PWMI1 from control device 30 with described dc voltage, to drive motor generator MG1.Therefore, motor generator MG1 is actuated to produce the moment of torsion by torque command value TR1 indication.

Be equipped with therein in the regenerative braking pattern of hybrid vehicle of motor driving apparatus 100, inverter 14 is based on the signal PWMC1 from control device 30, the AC voltage transformation that will be produced by motor generator MG1 is a dc voltage, via capacitor 13 dc voltage that obtains is offered booster converter 12.At this, described regenerative braking comprises the braking that is attended by regenerative electric power that realizes and the deceleration that is attended by regenerative electric power (or stopping to quicken) that realizes when driver's release the gas pedal of described hybrid vehicle and the described foot brake of inoperation when the driver of described hybrid vehicle steps on foot brake.

Reception is from the described dc voltage of capacitor 13, and inverter 31 is transformed to AC voltage based on the signal PWMI2 from control device 30 with described dc voltage, to drive motor generator MG2.Therefore, motor generator MG2 is actuated to produce the moment of torsion by torque command value TR2 indication.

Be equipped with therein in the regenerative braking pattern of hybrid vehicle of motor driving apparatus 100, inverter 31 is based on the signal PWMC2 from control device 30, the AC voltage transformation that will be produced by motor generator MG2 is a dc voltage, via capacitor 13 dc voltage that obtains is offered booster converter 12.

The current of electric MCRT1 that current sensor 24 detects the motor generator MG1 that flows through exports to control device 30 with the current of electric MCRT1 that will detect.The current of electric MCRT2 that current sensor 28 detects the motor generator MG2 that flows through exports to control device 30 with the current of electric MCRT2 that will detect.

Control device 30 receives from the dc voltage Vb of DC power supply B output from voltage sensor 10, receive current of electric MCRT1, MCRT2 from each current sensor 24,28, the output voltage V m that receives booster converters 12 from voltage sensor 20 (promptly, input voltage to inverter 14,31), and receive torque command value TR1, TR2, and motor revolution (number of the rotation of described motor) MRN1 and motor revolution MRN2 from external ECU (electric control unit).Control device 30 bases are hereinafter with the method for describing, based on output voltage V m, current of electric MCRT1 and torque command value TR1, generation is used for the signal PWMI1 or the signal PWMC1 of switching of the NPN transistor Q3-Q8 of control inverter 14, wherein inverter 14 is used to drive motor generator MG1, and exports the signal PWMI1 and the PWMC1 of described generation to inverter 14.

In addition, control device 30 bases are hereinafter with the method for describing, based on output voltage V m, current of electric MCRT2 and torque command value TR2, generation is used for the signal PWMI2 or the signal PWMC2 of switching of the NPN transistor Q3-Q8 of control inverter 31, wherein inverter 31 is used to drive motor generator MG2, and exports the signal PWMI2 and the PWMC2 of described generation to inverter 31.

In addition, when inverter 14 (or 31) drives motor generator MG1 (or MG2), control device 30 bases are hereinafter with the method for describing, based on dc voltage Vb, output voltage V m, torque command value TR1 (or TR2) and motor revolution MRN1 (or MRN2), generation is used to control the signal PWMU or the signal PWMD of switching of NPN transistor Q1, the Q2 of booster converter 12, and to the signal of the described generation of booster converter 12 outputs.

In addition, control device 30 produces the signal SE that is used for On/Off system relay SR1, SR2, so that this signal is exported to system relay SR1, SR2.

Fig. 2 is the functional block diagram of the control device 30 shown in Fig. 1.

With reference to Fig. 2, control device 30 comprises control device for inverter 301 and controller for transducer 302A.

Control device for inverter 301 produces signal PWMI1 or signal PWMC1 based on torque command value TR1, current of electric MCRT1 and voltage Vm, exports the signal of described generation with the NPN transistor Q3-Q8 to inverter 14.

More specifically, based on voltage Vm, current of electric MCRT1 and torque command value TR1, control device for inverter 301 calculates the voltage of each phase that will be applied to motor generator MG1, and, produce signal PWMI1 or the PWMC1 of each the NPN transistor Q3-Q8 that is used for actual unlatching/shutoff inverter 14 based on the described voltage that calculates.Then, control device for inverter 301 is exported the signal PWMI1 or the PWMC1 of described generation to each NPN transistor Q3-Q8 of inverter 14.

So, the switching Be Controlled of each NPN transistor Q3-Q8 of inverter 14, thus make, the electric current that flows to each phase of motor generator MG1 is controlled to export described moment of torsion according to described torque command by motor generator MG1.Like this, can control motor drive current, and according to torque command value TR1 output motor moment of torsion.

In addition, control device for inverter 301 based on voltage Vm, current of electric MCRT2 and torque command value TR2, produces signal PWMI2 or signal PWMC2 by method described above, exports the signal of described generation with the NPN transistor Q3-Q8 to inverter 31.

So, the switching Be Controlled of each NPN transistor Q3-Q8 of inverter 31, thus make, the electric current that flows to each phase of motor generator MG2 is controlled to export described moment of torsion according to described instruction by motor generator MG2.Like this, can control described motor drive current, and export described Motor torque according to torque command value TR2.

Determining from the relation between torque command value TR1 (or TR2) and the motor revolution MRN1 (or MRN2) whether the mode of operation of motor generator MG1 (or MG2) powers, that is, is electric motor mode or power generator (regeneration) pattern.At the trunnion axis or the x axle indication motor revolution MRN of this hypothesis rectangular coordinate system, and the longitudinal axis or y axle indication torque command value TR.Then, if described torque command value TR1 (or TR2) that is associated and motor revolution MRN1 (or MRN2) are positioned at first or second quadrant, then the mode of operation of motor generator MG1 (or MG2) is a powering mode.If described torque command value TR1 (or TR2) that is associated and motor revolution MRN1 (or MRN2) are positioned at the 3rd or four-quadrant, then the mode of operation of motor generator MG1 (or MG2) is a regeneration mode.

Therefore, if receive positive moment of torsion command value TR1 (or TR2), control device for inverter 301 produces and is used to drive the signal PWMI1 (or signal PWMI2) of motor generator MG1 (or MG2) as drive motor, export the signal of described generation with NPN transistor Q3-Q8 to inverter 14 (or 31), and, if receive negative torque command value TR1 (or TR2), then its generation is used to drive the signal PWMC1 (or signal PWMC2) that motor generator MG1 (or MG2) enters regeneration mode, exports the signal of described generation with the NPN transistor Q3-Q8 to inverter 14 (or 31).

Controller for transducer 302A basis is hereinafter with the method for describing, based on torque command value TR1 (or TR2), motor revolution MRN1 (or MRN2), dc voltage Vb and voltage Vm, produce signal PWMU or signal PWMD, with to the NPN transistor Q1 of described booster converter 12, the signal that Q2 exports described generation.

Fig. 3 is the functional block diagram of the controller for transducer 302A shown in Fig. 2.With reference to Fig. 3, controller for transducer 302A comprises voltage instruction computing unit 50, converter duty ratio ratio computing unit 52A and converter pwm signal converter unit 54.

Voltage instruction computing unit 50 is based on torque command value TR1 (or TR2) and motor revolution MRN1 (or MRN2) from external ECU, calculate the optimal value (desired value) of inverter input voltage, promptly, the voltage instruction value Vdc_com of booster converter 12, and export the voltage instruction value Vdc_com of described calculating to converter duty ratio ratio computing unit 52A.

Converter duty ratio ratio computing unit 52A calculates the duty ratio D_ON_1 of the NPN transistor Q1 of booster converter 12 based on from the voltage instruction Vdc_com of voltage instruction computing unit 50 with from the dc voltage Vb of voltage sensor 10 according to expression formula (1).

D_ON_1＝Vb/Vdc_com (1)

Then, converter duty ratio ratio computing unit 52A utilizes the duty ratio D_ON_1 of described calculating to calculate the duty ratio D_ON_2=1-D_ON_1 of NPN transistor Q2.

In addition, converter duty ratio ratio computing unit 52A receives from converter pwm signal converter unit 54 and is used to control the carrier frequency fc that NPN transistor Q1, Q2 switch, to calculate definite long T of control cycle by the carrier frequency fc of described reception.Converter duty ratio ratio computing unit 52A keeps the Dead Time Dt of NPN transistor Q1, Q2, and according to expression formula (2), calculates the maximum effectively duty ratio D_MAX of the NPN transistor Q1 of the influence of having removed Dead Time Dt.

D_MAX＝(T-Dt)/T (2)

Wherein, T-Dt represents that the effective control cycle definite by deduct Dead Time Dt from the long T of control cycle is long.

Then, utilize expression formula (1), converter duty ratio ratio computing unit 52A determines whether the duty ratio D_ON_1 that calculates based on voltage instruction value Vdc_com is influenced by Dead Time Dt.

More specifically, converter duty ratio ratio computing unit 52A determines whether that the described duty ratio D_ON_1 that calculates is greater than the effective duty ratio D_MAX of maximum, and less than the longest duty ratio that allows NPN transistor Q1 in the long T of control cycle, to be held open continuously (mean that described duty ratio is " 1 ", below as the same).If duty ratio D_ON_1 is greater than the effective duty ratio D_MAX of maximum and less than the longest described duty ratio, converter duty ratio ratio computing unit 52A determines that described duty ratio D_ON_1 is subjected to the influence of described Dead Time Dt.If duty ratio D_ON_1 is equal to or less than maximum effectively duty ratio D_MAX or equals the longest described duty ratio, converter duty ratio ratio computing unit 52A determines that described duty ratio D_ON_1 is not subjected to the influence of described Dead Time Dt.

Then, determine that at converter duty ratio ratio computing unit 52A described duty ratio D_ON_1 is subjected under the situation of described Dead Time Dt influence, converter duty ratio ratio computing unit 52A duty ratio D_ON_1 is set to maximum effectively duty ratio D_MAX or the longest described duty ratio.

On the contrary, determine that at converter duty ratio ratio computing unit 52A described duty ratio D_ON_1 is not subjected under the situation that described Dead Time Dt influences, converter duty ratio ratio computing unit 52A uses the duty ratio D_ON_1 that calculates by expression formula (1).

Fig. 4 shows the relation between duty ratio D_ON_1 and the voltage instruction value Vdc_com.

With reference to Fig. 4, when voltage instruction value Vdc_com equaled dc voltage Vb from DC power supply B, the duty ratio D_ON_1 of NPN transistor Q1 was the longest described duty ratio.Along with voltage instruction value Vdc_com is increased to greater than dc voltage Vb, according to expression formula (1), duty ratio D_ON_1 is inversely proportional to voltage instruction value Vdc_com and reduces.In other words, duty ratio D_ON_1 reduces along curve k1.

At duty ratio D_ON_1 greater than the effective duty ratio D_MAX of maximum and less than the described zone of long duty ratio, the duty ratio D_ON_1 that calculates based on voltage instruction value Vdc_com is partly taken by Dead Time, thereby can not guarantee described initial duty cycle.Then, in this case, duty ratio D_ON_1 is set to the longest described duty ratio.In other words, be equal to or greater than supply voltage Vb and be equal to or less than predetermined voltage Vdc_com_D that (in the described zone of=Vb * T/T-Dt), duty ratio D_ON_1 is set to the longest described duty ratio at voltage instruction value Vdc_com.

Can find out that from equation Vdc_com_D=Vb * T/T-Dt predetermined voltage Vdc_com_D relies on Dead Time Dt to determine.

At above-mentioned zone, the output voltage V m of boost pressure controller 12 vibration, thus can not be with respect to voltage instruction value Vdc_com by Linear Control.Therefore, duty ratio D_ON_1 is set to remove from it duty ratio (=1) of Dead Time Dt influence.

Subsequently, voltage instruction value Vdc_com reaches value Vdc_com_D, can carry out the Linear Control about the output voltage V m of voltage instruction value Vdc_com for this reason, thereafter, uses the duty ratio D_ON_1, the D_ON2 that calculate based on voltage instruction value Vdc_com.

Refer again to Fig. 3, according to said method, converter duty ratio ratio computing unit 52A calculates duty ratio D_ON_1, the D_ON_2 of NPN transistor Q1, Q2, and the ratio between duty ratio D_ON_1 and the D_ON_2 is outputed to converter pwm signal converter unit 54 as duty ratio ratio DR.

At this, converter duty ratio ratio computing unit 52A calculating voltage command value Vdc_com and from the deviation (Vdc_com-Vm) between the voltage Vm of voltage sensor 20 determines the duty ratio ratio then, and the deviation (Vdc_com-Vm) that calculates is equalled zero.

Based on described duty ratio ratio from converter duty ratio ratio computing unit 52A, converter pwm signal converter unit 54 produces signal PWMU or signal PWMD, with NPN transistor Q1, the Q2 of unlatching/shutoff booster converter 12, and the signal PWMU or the PWMD that are produced to NPN transistor Q1, the Q2 of booster converter 12 output.Further, the signal PWMU that produced to converter duty ratio ratio computing unit 52A output of converter pwm signal converter unit 54 or the carrier frequency fc of PWMD.

The duty ratio D_ON_2 that is included in the lower NPN transistor Q2 in the booster converter 12 can be increased, thereby increases the electrical power storage of reactor L1, realizes higher voltage output.On the contrary, if increase the duty ratio D_ON_1 of higher NPN transistor Q1, the voltage on the power line is lowered.So the duty ratio ratio DR by control NPN transistor Q1, Q2 can correspondingly control the voltage on the power line, thereby can voltage be set to be at least the free voltage of the output voltage of DC power supply B.

Fig. 5 A and 5B are respectively voltage and the duty ratio D_ON_1 time diagram of NPN transistor Q1 (upper arm).

With reference to Fig. 5 A and 5B, under the situation of carrying out boost operations, voltage instruction value Vdc_com begins to increase at moment t0.In moment t0 was during the t1 constantly, voltage instruction value Vdc_com quite approached the dc voltage Vb of DC power supply B output.Therefore, the duty ratio D_ON_1 that calculates based on voltage instruction value Vdc_com is subjected to Dead Time Dt influence.

Therefore, in moment t0 was during the t1 constantly, duty ratio D_ON_1 was fixed as the longest described duty ratio (D_ON_1=1.0) (seeing Fig. 5 B) of the influence of removing Dead Time Dt.In this case, when the output voltage V m of booster converter 12 offset voltage command value Vdc_com, duty ratio D_ON_1 is fixed as the longest duty ratio.Like this, be fixed as at duty ratio D_ON_1 under the state of described the longest duty ratio, carry out described boost operations.

In moment t0 was during the t1 constantly, output voltage V m correspondingly remained dc voltage Vb (seeing Fig. 5 A).

After this, voltage instruction value Vdc_com further increases, and the duty ratio D_ON_1 that calculates based on this voltage instruction value Vdc_com reaches like this, for example, and 0.95.Subsequently, duty ratio D_ON_1 is not influenced by Dead Time Dt.Therefore, use the duty ratio D_ON_1 and the D_ON_2 that calculate based on voltage instruction value Vdc_com to carry out boost operations.

If boost operations desires to make output voltage V m near dc voltage Vb, in moment t0 was during the t1 constantly, duty ratio D_ON_1 was fixed as the longest duty ratio, and, change based on voltage instruction value Vdc_com is linear in during other.

Therefore, for boosting and reduced pressure operation, when the duty ratio D_ON_1 of the NPN transistor Q1 that calculates based on voltage instruction value Vdc_com was influenced by Dead Time Dt, controller for transducer 302A controlled the switching of NPN transistor Q1, Q2 by duty ratio D_ON_1 being fixed as the duty ratio (the longest duty ratio) of removing Dead Time Dt influence.Under duty ratio D_ON_1 was not subjected to situation that Dead Time Dt influences, controller for transducer 302A utilized duty ratio D_ON_1 and the D_ON_2 that calculates based on voltage instruction value Vdc_com, the switching of control NPN transistor Q1, Q2.

Recently controlling under the situation of switching of NPN transistor Q1, Q2 by duty ratio D_ON_1 being fixed as the longest duty, controller for transducer 302A is along the path changing duty ratio D_ON_1 through the some A shown in Fig. 4, some B, some C and some D.

Therefore, shown in Fig. 5 A and 5B, though described step-up ratio near 1.0 zone in, promptly, in the zone of voltage instruction value Vdc_com near dc voltage Vb, the output voltage V m of booster converter 12 and also can be suppressed from the disturbance of the DC current Ib of DC power supply B.

With reference to Fig. 5 A and 5B, carry out reduced pressure operation at this hypothesis booster converter 12.In this case, near moment t1, duty ratio D_ON_1 is increased to the longest duty ratio (=1.0) suddenly from 0.95.D_ON_1 increases suddenly along with duty ratio, and output voltage V m is reduced to DC power supply Vb suddenly from the voltage instruction level (Vm=Vb/0.95) of hope.

Now above-mentioned phenomenon is applied to the motor driving apparatus 100 among Fig. 1.Along with the end-to-end voltage Vm of capacitor 13 at the instantaneous dc voltage Vb that is reduced to of moment t1, the stored energy that reduces the capacitor 13 of (Vm-Vb) corresponding to this voltage flows to DC power supply B from capacitor 13 at every turn.

At moment t1, at DC power supply B place, when capacitor 13 provided energy, the DC current Ib increased.So dc voltage Vb increases voltage △ Vb, it is corresponding to the product of the increment △ Ib of the internal resistance of DC power supply B and DC current Ib.

If the battery temperature of DC power supply B is in normal temperature range, internal resistance Rb is relatively low.Therefore, voltage increment △ Vb is corresponding less, and also corresponding less to the influence of dc voltage Vb.On the contrary, exceed normal temperature range if battery temperature is too low, the internal resistance Rb of DC power supply B can be quite high, thereby voltage increment △ Vb is relatively large.So the dc voltage Vb of DC power supply B exceeds the predetermined voltage that allows, and causes DC power supply B performance to reduce.

The performance of DC power supply B reduces and can effectively be prevented by following.(for example carrying out boost operations by booster converter 12, duty ratio D_ON_1=0.95) status transition stopped to boost operations in stage of state of (duty ratio D_ON_1=1.0), if the dc voltage Vb of DC power supply B can be increased to sizable degree, then described boost operations can not stop, but proceeds.

Particularly, with reference to controller for transducer 302A shown in Figure 3, only when the voltage level of the dc voltage Vb of DC power supply B is lower than the predetermined set value, converter duty ratio ratio computing unit 52A is just to the duty ratio ratio DR of converter pwm signal converter unit 54 output NPN transistor Q1, Q2.

More specifically, receive the dc voltage Vb from voltage sensor 10, converter duty ratio ratio computing unit 52A is according to said method computed duty cycle D_ON_1 and D_ON_2, and whether definite dc voltage Vb is less than predetermined set value Vb_lim.In other words, converter duty ratio ratio computing unit 52A determines whether dc voltage Vb exceeds in response to the unexpected variation of duty ratio D_ON_1 and allows maximum voltage Vb_MAX.This predetermined set value Vb_lim sets in advance based on expression formula (3), and is stored among the converter duty ratio ratio computing unit 52A.

Vb_lim＝Vb_MAX-Ib_max×Rb_max (3)

In expression formula (3), when duty ratio D_ON_1 when 0.95 changes to 1.0, that is, when transition occurred to the state that described boost operations stops, Vb_MAX represented the permission maximum voltage of DC power supply B, and Ib_max represents the maximum of DC current Ib.For Ib_max, the calculated value utilize expression formula (4) to calculate in advance is set, described expression formula (4) illustrates energy that capacitor 13 provided and the relation between the DC current Ib.Perhaps, the measured value based on the DC current Ib that obtains in advance is provided with it.

Vm-Vb＝1/C·(L·dIb/dt+Rb·Ib) (4)

C represents the capacitance of capacitor 13, and L represents the inductance of reactor L1.

Rb_max in the expression formula (3) represents the maximum of DC power supply B internal resistance Rb.Based on the specification that is installed in the DC power supply B on the motor driving apparatus 100, Rb_max is set in advance with above-mentioned maximum permissible voltage Vb_MAX.

When dc voltage Vb was equal to or greater than the value of setting Vb_lim, converter duty ratio ratio computing unit 52A determined that if described operation carries out the transition to the state that stops boost operations, dc voltage Vb will exceed permission maximum voltage Vb_MAX.So, do not carry out the transition to described halted state.Particularly, for example, converter duty ratio ratio computing unit 52A is fixed as maximum effectively duty ratio D_MAX with duty ratio D_ON_1, should carry out boost operations with indication.

On the contrary, as dc voltage Vb during less than the value of setting Vb_lim, converter duty ratio ratio computing unit 52A determines, even described boost operations stops, dc voltage Vb can not exceed yet and allows maximum voltage Vb_MAX.Thereby described operation carries out the transition to the state that boost operations stops.Particularly, converter duty ratio ratio computing unit 52A is fixed as the longest duty ratio (=1) with duty ratio D_ON_1, should stop boost operations to be used for indication.

Duty ratio D_ON_1 is being fixed as under the situation of maximum effectively duty ratio D_MAX with control NPN transistor Q1, Q2 switching, controller for transducer 302A is along the path changing duty ratio D_ON_1 of the some A shown in Fig. 4, some B, some C and some D.

Maximum effectively duty ratio D_MAX is determined by expression formula (2).At this, because the long T of control cycle in the expression formula (2) is definite by the carrier frequency fc that control NPN transistor Q1, Q2 switch, so maximum effectively duty ratio D_MAX can change according to carrier frequency fc.

Perhaps, because the switch cost of NPN transistor Q1, Q2 is associated with carrier frequency fc, determine maximum effectively duty ratio D_MAX so can consider carrier frequency fc and switch cost.

Fig. 6 is a flow chart, the operation of its explanation controller for transducer 302A, the voltage transformation of this device control booster converter 12.

With reference to Fig. 6, in the beginning of sequence of operations, converter duty ratio ratio computing unit 52A is based on from the voltage instruction value Vdc_com of voltage instruction computing unit 50 with calculate the duty ratio D_ON_1 (step S01) of NPN transistor Q1 (upper arm) according to expression formula (1) from the dc voltage Vb of voltage sensor 10.

Then, converter duty ratio ratio computing unit 52A is from converter pwm signal converter unit 54 reception carrier frequency f c, to calculate the long T of control cycle that is determined by the carrier frequency fc that has received.Converter duty ratio ratio computing unit 52A is with long T of control cycle and Dead Time Dt substitution expression formula (2), to calculate maximum effectively duty ratio D_MAX (step S02).

Afterwards, whether converter duty ratio ratio computing unit 52A determines duty ratio D_ON_1 greater than the effective duty ratio D_MAX of maximum, and less than the longest duty ratio (step S03).In other words, converter duty ratio ratio computing unit 52A determines whether duty ratio D_ON_1 is influenced by Dead Time Dt.

If duty ratio D_ON_1 is greater than the effective duty ratio D_MAX of maximum, and less than the longest duty ratio, converter duty ratio ratio computing unit 52A determines that duty ratio D_ON_1 is influenced by Dead Time Dt.Subsequently, converter duty ratio ratio computing unit 52A determines that whether dc voltage Vb is less than the value of setting Vb_lim (step S04).In other words, converter duty ratio ratio computing unit 52A determines whether DC power supply B may decreased performance.

As dc voltage Vb during less than the value of setting Vb_lim, converter duty ratio ratio computing unit 52A determines that DC power supply B performance can not descend, and duty ratio D_ON_1 is set to the longest duty ratio.Afterwards, based on set duty ratio D_ON_1, converter duty ratio ratio computing unit 52A computed duty cycle D_ON_2 (=1-D_ON_1).

The ratio of converter duty ratio ratio computing unit 52A between converter pwm signal converter unit 54 output duty cycle D_ON_1 (=1) and duty ratio D_ON2 (=0) is as duty ratio ratio DR.

Based on the duty ratio ratio DR from converter duty ratio ratio computing unit 52A, converter pwm signal converter unit 54 generation signal PWMU or signal PWMD are to export the signal that is produced to NPN transistor Q1 and Q2.Therefore, the duty ratio D_ON_1 of long duty ratio controls (step S05) by being set in the switching of NPN transistor Q1 and Q2.

On the contrary, when dc voltage Vb was equal to or greater than the value of setting Vb_lim, converter duty ratio ratio computing unit 52A determined that DC power supply B may decreased performance, and duty ratio D_ON_1 is set to maximum effectively duty ratio D_MAX.Based on set duty ratio D_ON_1, converter duty ratio ratio computing unit 52A computed duty cycle D_ON2 (=1-D_ON_1).

Converter duty ratio ratio computing unit 52A to converter pwm signal converter unit 54 output duty cycle D_ON_1 (=D_MAX) and duty ratio D_ON_2 (=ratio between 1-D_MAX) is as duty ratio ratio DR.

Based on the duty ratio ratio DR from converter duty ratio ratio computing unit 52A, converter pwm signal converter unit 54 produces signal PWMU or signal PWMD with to NPN transistor Q1, Q2 output signal.Like this, utilize the duty ratio D_ON_1 that is set to maximum effective duty ratio D_MAX to control the switching (step S06) of NPN transistor Q1, Q2.

After this, duty ratio D_ON_1 is fixed as the longest duty ratio or maximum effectively duty ratio D_MAX, reach maximum effectively duty ratio D_MAX up to duty ratio D_ON_1, and repeated execution of steps S01 is to step S07.When duty ratio D_ON_1 reaches maximum effectively duty ratio D_MAX, and determine that in step S03 duty ratio D_ON_1 is equal to or less than maximum effectively duty ratio D_MAX, when perhaps equaling the longest duty ratio, converter duty ratio ratio computing unit 52A calculates the duty ratio D_ON_1 that calculates based on voltage instruction value Vdc_com and the ratio between the duty ratio D_ON2, as duty ratio ratio DR, with the duty ratio ratio that calculates to 54 outputs of converter pwm signal converter unit.

Based on the duty ratio ratio DR from converter duty ratio ratio computing unit 52A, converter pwm signal converter unit 54 generation signal PWMU or signal PWMD are to export the signal that is produced to NPN transistor Q1 and Q2.Thereby, utilize the duty ratio D_ON_1 that calculates based on voltage instruction value Vdc_com and the switching (step S07) of duty ratio D_ON2 control NPN transistor Q1 and Q2.So far, finish this a series of operations.

In the flow chart of Fig. 6, dc voltage Vb and which bigger determining of the value of setting Vb_lim also can be made according to the method in following first and second modified examples of pointing out shown in the step S04.Each motor driving apparatus in described first and second modified examples is to comprise controller for transducer 302B, 302C, rather than the equipment of the controller for transducer 302A in the control device 30 of motor driving apparatus 100 among Fig. 1.Therefore, public element and feature are not repeated in this description.

First modified example

Fig. 7 is the functional block diagram according to the controller for transducer 302B of the motor driving apparatus of first modified example of first embodiment of the invention.With reference to Fig. 7, replace the converter duty ratio ratio computing unit 52A of the controller for transducer 302A among Fig. 3, controller for transducer 302B comprises converter duty ratio ratio computing unit 52B.

Converter duty ratio ratio computing unit 52B receives the voltage instruction value Vdc_com from voltage instruction computing unit 50, dc voltage Vb from voltage sensor 10, internal resistance Rb from battery ECU (not shown), from the output voltage V m of booster converter 12, and from the carrier frequency fc of converter pwm signal converter unit 54.Based on voltage instruction value Vdc_com and dc voltage Vb, converter duty ratio ratio computing unit 52B calculates the duty ratio D_ON_1 and the D_ON_2 of booster converter 12 according to said method.

Further, converter duty ratio ratio computing unit 52B determines whether the duty ratio D_ON_1 that calculates based on voltage instruction value Vdc_com is influenced by Dead Time Dt.The concrete grammar that should determine is identical with definite method (corresponding to the step S03 among Fig. 6) that above-mentioned converter duty ratio ratio computing unit 52A is carried out.

In addition, when converter duty ratio ratio computing unit 52B determined that duty ratio D_ON_1 is influenced by Dead Time Dt, converter duty ratio ratio computing unit 52B determined according to method described below whether dc voltage Vb will have the possibility of decreased performance.

Converter duty ratio ratio computing unit 52B determines that whether dc voltage Vb is less than the value of setting Vb_lim.The difference of this modified example and converter duty ratio ratio computing unit 52A is to be provided with the method for this value of setting Vb_lim.

More specifically, converter duty ratio ratio computing unit 52B is provided with this value of setting Vb_lim based on expression formula (5).

Vb_lim＝Vb_MAX-Ib_max×Rb (5)

Vb_MAX in the expression formula (5) is identical with aforementioned expression formula (3) to expression formula (5) with Ib_max.Particularly, based on the measured value that utilizes predetermined calculated value of expression formula (4) or DC current Ib Ib_max is set.

Further, in expression formula (5), Rb is the actual measured value of DC power supply B internal resistance Rb.As shown in Figure 7, the actual measured value of internal resistance Rb is provided as the battery information from battery ECU (not shown).

This modified example uses the actual measured value of internal resistance Rb to determine the reasons are as follows of dc voltage Vb.Shown in expression formula (3), the converter duty ratio ratio computing unit 52A among Fig. 3 uses the maximum Rb_max of the internal resistance Rb of DC power supply B to determine voltage increment △ Vb.Therefore, consider worst state (corresponding to the state of internal resistance Rb maximum) all the time, and determine whether to carry out the transition to the state (duty ratio D_ON_1=1) that stops boost operations.Therefore,, such situation can be occurred, when carrying out described transition, the state that boost operations is stopped can not be carried out the transition to when actual because internal resistance Rb is less relatively.Then, in this modified example, converter duty ratio ratio computing unit 52B uses the battery information (internal resistance Rb) of described battery ECU, determines whether DC power supply B can decreased performance.So the vibration of output voltage V m and DC current Ib can be reduced more accurately, and avoid DC power supply B to be damaged.

Converter duty ratio ratio computing unit 52B determines that dc voltage Vb is whether less than the value Vb_lim of the setting that is provided with according to said method, and according to described definite result, duty ratio D_ON_1 is set to the longest described duty ratio or maximum effectively duty ratio D_MAX.Then, converter duty ratio ratio computing unit 52B is to converter pwm signal converter unit 54 output duty cycle ratio DR, and described duty ratio ratio DR is the ratio between duty ratio D_ON_1 (=1 or D_MAX) and the duty ratio D_ON2 (=0 or 1-D_MAX).

Second modified example

Fig. 8 is the functional block diagram according to the controller for transducer 302C of the motor driving apparatus of second modified example of first embodiment of the invention.With reference to Fig. 8, replace the converter duty ratio ratio computing unit 52A of the controller for transducer 302A among Fig. 3, controller for transducer 302C comprises converter duty ratio ratio computing unit 52C.

Converter duty ratio ratio computing unit 52C receives the voltage instruction value Vdc_com from voltage instruction computing unit 50, dc voltage Vb from voltage sensor 10, battery temperature Tb from the temperature sensor (not shown) of the battery temperature that is used to detect DC power supply B, from the output voltage V m of booster converter 12, and from the carrier frequency fc of converter pwm signal converter unit 54.Then, based on voltage instruction value Vdc_com and dc voltage Vb, converter duty ratio ratio computing unit 52C calculates the NPN transistor Q1 of booster converter 12 and duty ratio D_ON_1 and the D_ON_2 of Q2 according to said method.

In addition, converter duty ratio ratio computing unit 52C determines whether the duty ratio D_ON_1 that calculates based on voltage instruction value Vdc_com is influenced by Dead Time Dt.Determine that the concrete of this method is identical with definite method (corresponding to the step S03 among Fig. 6) of being undertaken by above-mentioned converter duty ratio ratio computing unit 52A.

In addition, when converter duty ratio ratio computing unit 52C determined that duty ratio D_ON_1 is influenced by Dead Time Dt, converter duty ratio ratio computing unit 52C determined according to method described below whether dc voltage Vb has the possibility of decreased performance.

Converter duty ratio ratio computing unit 52C determines that whether dc voltage Vb is less than the value of setting Vb_lim.This modified example is the method to set up of this value of setting Vb_lim with the difference of converter duty ratio ratio computing unit 52A, 52B.

More specifically, converter duty ratio ratio computing unit 52C is provided with this value of setting Vb_lim based on aforementioned expression formula (5).The characteristics of this modified example are, converter duty ratio ratio computing unit 52C estimates internal resistance Rb in the expression formula (5) based on the battery temperature Tb from described temperature sensor.

Described first modified example is configured to use the actual measured value of internal resistance Rb as the Rb in the expression formula (5), and because any simple battery ECU does not all possess the device that is used to measure or estimate internal resistance Rb, therefore, this modified example will be used to estimate that the device of internal resistance Rb is provided to converter duty ratio ratio computing unit 52C.

Because the internal resistance Rb of DC power supply B depends on battery temperature Tb to a great extent, therefore, can provide the described device that is used to estimate internal resistance Rb by the association of in converter duty ratio ratio computing unit 52, storing between internal resistance Rb and the battery temperature Tb with the form of mapping graph or transformation for mula.Based on the internal resistance Rb that is associated by the detected battery temperature Tb of described temperature sensor, converter duty ratio ratio computing unit 52C calculating and setting value Vb_lim.Then, whether converter duty ratio ratio computing unit 52C determines dc voltage Vb less than the described value of the setting Vb_lim that calculates, and according to described definite result, duty ratio D_ON_1 is set to the longest described duty ratio or maximum effectively duty ratio D_MAX.Converter duty ratio ratio computing unit 52C is to converter pwm signal converter unit 54 output duty cycle ratio DR, and described duty ratio ratio DR is the ratio between duty ratio D_ON_1 (=1 or D_MAX) and the duty ratio D_ON_2 (=0 or 1-D_MAX).

According to described first embodiment and first and second modified examples thereof, the maximum Ib_max of DC current Ib is contained in expression formula (3) and (5), and carry out the transition to the operation of boost operations halted state based on it, and, based on the value that is used to indicate the energy that provides from capacitor 13 and the relationship expression (4) between the DC current Ib to calculate in advance, perhaps, the measured value based on the DC current Ib that obtains in advance is provided with described Ib_max.Yet, also can be in converter duty ratio ratio computing unit 52A each computed duty cycle D_ON_1, D_ON_2 in 52C, calculate maximum Ib_max based on the output voltage V m that receives from booster converter 12, with the control precision of further raising controller for transducer 302A to 302C.

Under the motor driving apparatus shown in Fig. 1 100 is installed in situation on the hybrid vehicle, motor generator MG1 is connected with described engine by power distribution unit, and motor generator MG2 is connected with front-wheel (driving wheel) by described power distribution unit.When the described just in motion brake pedal of described hybrid vehicle is operated, to stop motor generator MG1, thereby reduce under the condition of the voltage that will offer motor generator MG2, perhaps, when described hybrid vehicle just at low speed driving, stop the generating of motor generator MG1, thereby reduce under the condition of the voltage that will offer motor generator MG2, booster converter 12 carries out described reduced pressure operation.Under this condition, controller for transducer 302A is to the level of 302C according to dc voltage Vb, by along through the path of the some D shown in Fig. 4, some C, some B and some A or through the path changing duty ratio D_ON_1 of a some D, some C, some E and some A, control booster converter 12, so that output voltage V m is reduced to voltage instruction value Vdc_com.Therefore, even when described hybrid vehicle deceleration or low speed driving, still can reduce the vibration of output voltage V m and DC current Ib, and avoid DC power supply B to be damaged.

In addition, in fact the controller for transducer 302A of control device 30 is undertaken by CPU (CPU) to the voltage transformation control of 302C.Described CPU reads the program that has comprised the step of flow chart shown in Fig. 6 from ROM (read-only memory), carries out the program that is read, and follows flow chart shown in Figure 6 and control described voltage transformation.Therefore, described ROM is corresponding to computer (CPU) readable medium recording program performing of the program that records the step that has comprised flow chart shown in Figure 6 thereon.

And booster converter 12 and control device 30 are corresponding to " voltage conversion device ".

In addition, NPN transistor Q1 is corresponding to " upper arm ", and NPN transistor Q2 is corresponding to " underarm ".

In addition, maximum effectively duty ratio D_MAX refers to " suitable duty ratio ".

Second embodiment

In the above-described embodiments, under duty ratio D_ON_1 is subjected to situation that Dead Time Dt influences, controller for transducer 302A to 302C in the transition of determining to proceed under the condition that DC power supply B will can not be damaged the state that described boost operations is stopped.The unexpected increase of the DC current Ib in the time of therefore, can avoiding owing to the status transition that is stopped to described boost operations damages described DC power supply B.

Perhaps, can not be subjected to the infringement of the unexpected increase (after this being called surge) of DC current Ib by allowing Linear Control duty ratio D_ON_1 protection DC power supply B.

Then, present embodiment discloses a kind of voltage conversion device that can control duty ratio D_ON_1 linearly.

Fig. 9 is the functional block diagram according to the controller for transducer 302G of the motor driving apparatus of second embodiment of the invention.With reference to Fig. 9, replace converter duty ratio ratio computing unit 52A and the converter pwm signal converter unit 54 of the controller for transducer 302A among Fig. 3, controller for transducer 302G comprises converter duty ratio ratio computing unit 52G and converter pwm signal converter unit 54G.

Converter duty ratio ratio computing unit 52G receives the voltage instruction value Vdc_com from voltage instruction computing unit 50, dc voltage Vb from voltage sensor 10, internal resistance Rb from battery ECU (not shown), from the output voltage V m of booster converter 12, and from the carrier frequency fc of converter pwm signal converter unit 54G.Based on voltage instruction value Vdc_com and dc voltage Vb, converter duty ratio ratio computing unit 52G calculates the NPN transistor Q1 of booster converter 12 and duty ratio D_ON_1 and the D_ON_2 of Q2 according to aforementioned expression formula (1).In addition, based on carrier frequency fc, converter duty ratio ratio computing unit 52G calculates the maximum effectively duty ratio D_MAX of the NPN transistor Q1 of the influence of having removed Dead Time Dt according to expression formula (2).In the present embodiment, suppose that the described maximum effectively duty ratio D_MAX that calculates is 0.95.

Then, converter duty ratio ratio computing unit 52G determines whether the duty ratio D_ON_1 that calculates based on voltage instruction value Vdc_com is influenced by Dead Time Dt.Determine that the concrete of this method is identical with definite method (corresponding to the step S03 among Fig. 6) that above-mentioned converter duty ratio ratio computing unit 52A is carried out.Particularly, as the described duty ratio D_ON_1 that calculates during greater than the effective duty ratio D_MAX of maximum and less than described the longest duty ratio, converter duty ratio ratio computing unit 52G determines that described duty ratio D_ON_1 is subjected to the influence of described Dead Time Dt.When duty ratio D_ON_1 was equal to or less than maximum effectively duty ratio D_MAX or equal described the longest duty ratio, converter duty ratio ratio computing unit 52G determined that described duty ratio D_ON_1 is not subjected to the influence of described Dead Time.

When converter duty ratio ratio computing unit 52G determined that duty ratio D_ON_1 is influenced by Dead Time Dt, converter duty ratio ratio computing unit 52G utilized maximum effectively duty ratio D_MAX and the longest described duty ratio that duty ratio D_ON_1 is set.

Particularly, converter duty ratio ratio computing unit 52G switches between effective duty ratio D_MAX of maximum and the longest described duty ratio (=1), satisfying predetermined ratio CR, thereby make the duty ratio that finally obtains equal the duty ratio D_ON_1 that calculates based on voltage instruction value Vdc_com.In this case, converter duty ratio ratio computing unit 52G is provided with the feasible relation that satisfies definition in the expression formula (6) of this predetermined ratio CR:

D_ON_1＝D_MAX×z+1×(1-z) (6)

Wherein, z is for using the maximum effectively ratio of duty ratio D_MAX (z is 0 to be 1 arbitrary value to the maximum for minimum), and D_MAX is 0.95.

For example, when the duty ratio D_ON_1 that calculates based on voltage instruction value Vdc_com is 0.96, determine that from expression formula (6) z equals 0.8 (z=0.8).Particularly, between effective duty ratio D_MAX of maximum and the longest described duty ratio (=1), switch, satisfying ratio 4:1, thereby obtain desired duty ratio D_ON_1=0.96.

In this case, converter duty ratio ratio computing unit 52G exports predetermined ratio CR (that is D_MAX (=0.95): the longest duty ratio (=1)=4:1) of described setting to converter pwm signal converter unit 54G.

On the contrary, when converter duty ratio ratio computing unit 52G determined that duty ratio D_ON_1 is not influenced by Dead Time Dt, converter duty ratio ratio computing unit 52G used the duty ratio D_ON_1 that calculates according to expression formula (1).Then, the duty ratio ratio DR of converter duty ratio ratio computing unit 52G between converter pwm signal converter unit 54G output duty cycle D_ON_1 and duty ratio D_ON_2.

At this, converter duty ratio ratio computing unit 52G calculates at voltage instruction value Vdc_com with from the deviation (Vdc_com-Vm) between the voltage Vm of voltage sensor 20, and calculate described duty ratio ratio DR, make the described deviation that calculates (Vdc_com-Vm) equal zero.

Figure 10 shows the relation between duty ratio D_ON_1 and the voltage instruction value Vdc_com.

With reference to Figure 10, when voltage instruction value Vdc_com equaled dc voltage Vb from DC power supply B output, the duty ratio D_ON_1 of NPN transistor Q1 was the longest described duty ratio.Along with voltage instruction value Vdc_com is increased to greater than dc voltage Vb, can find out that from expression formula (1) duty ratio D_ON_1 reduces in contrast to voltage instruction value Vdc_com.In other words, duty ratio D_ON_1 reduces along curve k1.

At duty ratio D_ON_1 greater than the effective duty ratio D_MAX of maximum and less than the described zone of long duty ratio, the duty ratio D_ON_1 that calculates based on voltage instruction value Vdc_com is partly taken by Dead Time Dt, thereby can not guarantee described initial duty cycle.Therefore, in this case, duty ratio D_ON_1 is switched between effective duty ratio D_MAX of maximum and the longest described duty ratio with predetermined ratio CR.Therefore, (zone of=Vb * T/T-Dt), duty ratio D_ON_1 reduces along curve k1 even be equal to or greater than supply voltage Vb and be equal to or less than predetermined voltage Vdc_com_D at voltage instruction value Vdc_com.So,, can control the output voltage V m of booster converter 12 about voltage instruction value Vdc_com linearly, and not influenced by Dead Time Dt even in this zone.

After voltage instruction value Vdc_com reaches predetermined voltage Vdc_com_D, use the duty ratio D_ON_1, the D_ON_2 that calculate based on voltage instruction value Vdc_com.

Because Vdc_com_D equals Vb * T/T-Dt, determines predetermined voltage Vdc_com_D according to Dead Time Dt.

Referring again to Fig. 9, based on described duty ratio ratio DR or predetermined ratio CR from converter duty ratio ratio computing unit 52G, converter pwm signal converter unit 54G produces signal PWMU or the signal PWMD that is used to open/turn-off NPN transistor Q1, Q2, and to the NPN transistor Q1 of booster converter 12, signal PWMU or the PWMD that Q2 exports described generation.Converter pwm signal converter unit 54G exports the signal PWMU of described generation or the carrier frequency fc of PWMD to converter duty ratio ratio computing unit 52G.

Figure 11 is by the time diagram of converter pwm signal converter unit 54G based on the signal PWMU of predetermined ratio CR generation.

With reference to Figure 11, signal PWMU1 is imported into the base terminal of the NPN transistor Q1 of booster converter 12, and signal PWMU2 is imported into the base terminal of NPN transistor Q2.Signal PWMU1, PWMU2 be when the duty ratio D_ON_1 that calculates based on voltage instruction value Vdc_com be 0.96 and predetermined ratio CR be (D_MAX (=0.95): the signal that produces by converter pwm signal converter unit 54G in the time of 1=4:1).

From Figure 11 as seen, signal PWMU1 comprises the maximum effectively duty ratio D_MAX of all four long T of control cycle and the longest described duty ratio (=1) of a long T of control cycle.Therefore, in the long T of each control cycle, locate at effective duty ratio D_MAX of maximum or the longest described duty ratio (=1), NPN transistor Q1 opens.Then, through five long T of control cycle, finally realize desired 0.96 duty ratio D_ON_1.

Figure 12 A and 12B are respectively the voltage of NPN transistor Q1 (upper arm) and the time diagram of duty ratio D_ON_1.

With reference to Figure 12 A and 12B, under the situation of carrying out boost operations, voltage instruction value Vdc_com begins to increase at moment t0.During from moment t0 to moment t1, the duty ratio D_ON_1 that calculates based on voltage instruction value Vdc_com is subjected to the influence of Dead Time Dt.

Therefore, during from moment t0 to moment t1 in, duty ratio D_ON_1 is set to switch between effective duty ratio D_MAX of maximum (for example, 0.95) and the longest described duty ratio (=1) with predetermined ratio CR.So shown in Figure 12 B, duty ratio D_ON_1 was controlled linearly when described voltage raise.

Therefore, during from moment t0 to moment t1 in, output voltage V m and voltage instruction value Vdc_com are complementary, and along with the increase of voltage instruction value Vdc_com linear change.

So, being about 1.0 and the voltage instruction value Vdc_com zone of approaching dc voltage Vb in described step-up ratio, the disturbance of the output voltage V m of booster converter 12 and DC current Ib is suppressed.

Figure 13 is a flow chart, and it has illustrated the operation of the voltage transformation of controller for transducer 302G control booster converter 12.

With reference to Figure 13, beginning in sequence of operations, converter duty ratio ratio computing unit 52G calculates the duty ratio D_ON_1 (step S50) of NPN transistor Q1 (upper arm) based on from the voltage instruction value Vdc_com of voltage instruction computing unit 50 with from the dc voltage Vb of voltage sensor 10 according to expression formula (1).

Then, converter duty ratio ratio computing unit 52G is from converter pwm signal converter unit 54G reception carrier frequency f c, to calculate definite long T of control cycle by the carrier frequency fc of described reception.Converter duty ratio ratio computing unit 52G is with long T of control cycle and Dead Time Dt substitution expression formula (2), to calculate maximum effectively duty ratio D_MAX (step S51).

After this, converter duty ratio ratio computing unit 52G determines whether that duty ratio D_ON_1 is greater than the effective duty ratio D_MAX of maximum and less than the longest described duty ratio (step S52).In other words, converter duty ratio ratio computing unit 52G determines whether duty ratio D_ON_1 is influenced by Dead Time Dt.

If duty ratio D_ON_1 is greater than the effective duty ratio D_MAX of maximum and less than the longest described duty ratio, converter duty ratio ratio computing unit 52G determines that duty ratio D_ON_1 is influenced by Dead Time Dt, and with duty ratio D_ON_1, maximum effectively duty ratio D_MAX and the longest described duty ratio (=1) substitution expression formula (6) to calculate predetermined ratio CR (step S53).Then, converter duty ratio ratio computing unit 52G is to the described predetermined ratio CR that calculates of converter pwm signal converter unit 54G output.

Converter pwm signal converter unit 54G produces signal PWMU or signal PWMD, and exports the signal of described generation to NPN transistor Q1, Q2 based on the predetermined ratio CR from converter duty ratio ratio computing unit 52G.Therefore, by between effective duty ratio D_MAX of maximum and the longest described duty ratio, switching the switching (step S54) of controlling NPN transistor Q1, Q2 with predetermined ratio CR.

Afterwards, between the longest described duty ratio and maximum effective duty ratio D_MAX, switch, reach maximum effectively duty ratio D_MAX up to duty ratio D_ON_1, and repeat step S50 to step S54 with predetermined ratio CR.Then, when duty ratio D_ON_1 reaches maximum effectively duty ratio D_MAX, determine that in step S52 duty ratio D_ON_1 is equal to or less than maximum effectively duty ratio D_MAX, perhaps equal the longest described duty ratio, converter duty ratio ratio computing unit 52G computed duty cycle ratio DR, described duty ratio ratio DR is the duty ratio D_ON_1 that calculates based on voltage instruction value Vdc_com and the ratio between the duty ratio D_ON_2, and to the described duty ratio ratio DR that calculates of converter pwm signal converter unit 54G output.

Based on the duty ratio ratio DR from converter duty ratio ratio computing unit 52G, converter pwm signal converter unit 54G produces signal PWMU or signal PWMD, and exports the signal of described generation to NPN transistor Q1, Q2.Therefore, utilize the duty ratio D_ON_1, the duty ratio D_ON_2 that determine based on voltage instruction value Vdc_com, the switching (step S55) of control NPN transistor Q1, Q2.So, finish described sequence of operations.

At this, with reference to the flow chart among Figure 13, whether the definite duty ratio D_ON_1 shown in the step S52 influenced by Dead Time Dt can be realized according to the method for describing in following first modified example.

First modified example

Figure 14 is the theory diagram of described motor driving apparatus, and described motor driving apparatus has the voltage conversion device according to first modified example of second embodiment of the invention.

With reference to Figure 14, compare with the motor driving apparatus 100 among Fig. 1, motor driving apparatus 100H also comprises the current sensor 32 that is used to detect the DC current Ib.Current sensor 32 detects the DC current Ib, and to the described detected DC current Ib of control device 30 outputs.

Controller for transducer 302G in the alternate figures 9, the control device 30 in this modified example comprises controller for transducer 302H.So, publicly-owned assembly is not repeated to describe in detail.

Figure 15 is the functional block diagram of controller for transducer 302H, and this device 302H is contained in the control device 30 among Figure 14.With reference to Figure 15, replace the converter duty ratio ratio computing unit 52G of the controller for transducer 302G among Fig. 9, controller for transducer 302H comprises converter duty ratio ratio computing unit 52H.

Converter duty ratio ratio computing unit 52H receives the voltage instruction value Vdc_com from voltage instruction computing unit 50, dc voltage Vb from voltage sensor 10, internal resistance Rb from battery ECU (not shown), output voltage V m from booster converter 12, from the carrier frequency fc of converter pwm signal converter unit 54, and from the DC current Ib of current sensor 32.Based on voltage instruction value Vdc_com and dc voltage Vb, converter duty ratio ratio computing unit 52H utilizes aforementioned expression formula (1) to calculate duty ratio D_ON_1, the D_ON_2 of NPN transistor Q1, the Q2 of booster converter 12.

In addition, converter duty ratio ratio computing unit 52H determines whether the duty ratio D_ON_1 that calculates based on voltage instruction value Vdc_com is influenced by Dead Time Dt.In this modified example, converter duty ratio ratio computing unit 52H determines based on the surge whether the DC current Ib takes place whether duty ratio D_ON_1 is influenced by Dead Time Dt.

More specifically, converter duty ratio ratio computing unit 52H is provided by the slope (△ Ib/ △ t) of the output waveform of the DC current Ib that provides from current sensor 32, and determines whether described slope exceeds predetermined threshold.In this case, if the slope of the output waveform of described DC current Ib exceeds described predetermined threshold, converter duty ratio ratio computing unit 52H determines to have taken place in the DC current Ib unexpected variation (surge).Then, based in definite DC current Ib surge having taken place, converter duty ratio ratio computing unit 52H determines that duty ratio D_ON_1 is influenced by Dead Time Dt.On the contrary, when the slope of the output waveform of described DC current Ib is equal to or less than described predetermined threshold, converter duty ratio ratio computing unit 52H determines not take place in the DC current Ib surge.At this moment, converter duty ratio ratio computing unit 52H determines that duty ratio D_ON_1 is not influenced by Dead Time Dt.

When converter duty ratio ratio computing unit 52H determined that duty ratio D_ON_1 is influenced by Dead Time Dt, computing unit 52H utilized maximum effectively duty ratio D_MAX and the longest described duty ratio that duty ratio D_ON_1 is set.Concrete method to set up be that the described method of converter duty ratio ratio computing unit 52G is identical among Fig. 9.In other words, converter duty ratio ratio computing unit 52H switches between effective duty ratio D_MAX of maximum and the longest described duty ratio (=1) with predetermined ratio CR, so that the duty ratio that finally obtains is complementary with the duty ratio D_ON_1 that calculates based on voltage instruction value Vdc_com.

On the contrary, when converter duty ratio ratio computing unit 52H determined that duty ratio D_ON_1 is not influenced by Dead Time Dt, computing unit 52H used the duty ratio D_ON_1 that calculates from expression formula (1).Then, converter duty ratio ratio computing unit 52H is to converter pwm signal converter unit 54G output duty cycle ratio DR, and described duty ratio ratio DR is the ratio between duty ratio D_ON_1 and the duty ratio D_ON_2.

Figure 16 is a flow chart, and it has illustrated the operation of the voltage transformation of described controller for transducer 302H control booster converter 12.

With reference to Figure 16, beginning in sequence of operations, converter duty ratio ratio computing unit 52H calculates the duty ratio D_ON_1 (step S50) of NPN transistor Q1 (upper arm) based on from the voltage instruction value Vdc_com of voltage instruction computing unit 50 with from the dc voltage Vb of voltage sensor 10 according to expression formula (1).

Then, converter duty ratio ratio computing unit 52H is from converter pwm signal converter unit 54G reception carrier frequency f c, to calculate definite long T of control cycle by the carrier frequency fc of described reception.Converter duty ratio ratio computing unit 52H is with long T of control cycle and Dead Time Dt substitution expression formula (2), to calculate maximum effectively duty ratio D_MAX (step S51).

After this, converter duty ratio ratio computing unit 52H determines that whether the slope (△ Ib/ △ t) of the output waveform of DC current Ib is greater than predetermined threshold (step S520).Particularly, based on the surge whether the DC current Ib takes place, converter duty ratio ratio computing unit 52H determines whether duty ratio D_ON_1 is influenced by Dead Time Dt.

When the slope of the output waveform of described DC current Ib during greater than described predetermined threshold, converter duty ratio ratio computing unit 52H determines that duty ratio D_ON_1 is influenced by Dead Time Dt, and with duty ratio D_ON_1, maximum effectively duty ratio D_MAX and the longest described duty ratio (=1) substitution expression formula (6) to determine predetermined ratio CR (step S53).Then, converter duty ratio ratio computing unit 52H is to the described predetermined ratio CR that calculates of converter pwm signal converter unit 54G output.

Based on the predetermined ratio CR from converter duty ratio ratio computing unit 52H, converter pwm signal converter unit 54G produces signal PWMU or signal PWMD, and exports the signal of described generation to NPN transistor Q1, Q2.So, by between effective duty ratio D_MAX of maximum and the longest described duty ratio, switching the switching (step S54) of controlling NPN transistor Q1, Q2 with predetermined ratio CR.

After this, between the longest described duty ratio and maximum effective duty ratio D_MAX, switch, reach maximum effectively duty ratio D_MAX up to duty ratio D_ON_1, and repeat step S50 to step S54 with predetermined ratio CR.When the slope of determining the output waveform of DC current Ib in step S520 is equal to or less than described predetermined threshold, converter duty ratio ratio computing unit 52H computed duty cycle ratio DR, wherein said duty ratio ratio DR is the duty ratio D_ON_1 that calculates based on voltage instruction value Vdc_com and the ratio between the duty ratio D_ON_2, and to the described duty ratio ratio DR that calculates of converter pwm signal converter unit 54G output.

Based on the duty ratio ratio DR from converter duty ratio ratio computing unit 52H, converter pwm signal converter unit 54G produces signal PWMU or signal PWMD, and exports the signal of described generation to NPN transistor Q1, Q2.So, utilize the duty ratio D_ON_1 and the duty ratio D_ON_2 that calculate based on voltage instruction value Vdc_com, the switching (step S55) of control NPN transistor Q1, Q2.Then, finish described sequence of operations.

As above discuss, according to a second embodiment of the present invention, described duty ratio is Be Controlled linearly, and not influenced by described Dead Time.Therefore, can prevent the unexpected variation in the DC electric current, and avoid bringing any infringement to described DC power supply.

It may be noted that similar in appearance to the control of controller for transducer 302A, the control of the voltage transformation of controller for transducer 302G, 302H is in fact also carried out by CPU to the voltage transformation of 302C.Described CPU reads each the program of step that comprises in the flow chart shown in Figure 13 and Figure 16 from ROM, carry out the program that is read, and follow Figure 13 and flow chart shown in Figure 16 each control described voltage transformation.Therefore, described ROM is corresponding to the computer that has write down program thereon (CPU) readable medium recording program performing, and wherein said program has comprised each the step in Figure 13 and the flow chart shown in Figure 16.

In addition, the longest described duty ratio is corresponding to " second duty ratio " when described supply voltage is described voltage instruction value.Maximum effectively duty ratio D_MAX is corresponding to " first duty ratio " when the voltage that is equal to or greater than predetermined voltage is described voltage instruction value.In the present embodiment, although " first duty ratio " is the duty ratio when described supply voltage is described voltage instruction value, it is not limited to situation described here.Perhaps, " first duty ratio " can be any duty ratio when the voltage that is equal to or greater than predetermined voltage is described voltage instruction value, the influence of having removed described Dead Time therein.

The 3rd embodiment

About described first and second embodiment, the example that described Dead Time Dt exerts an influence to duty ratio D_ON_1 has more than been described, when the duty ratio D_ON_1 of described upper arm approach 1.0 regional the time, described duty ratio can not be by Linear Control.And provided description to the method for avoiding the vibration of output voltage V m and DC current Ib.

As shown in figure 17, Dead Time Dt is to have error between duty ratio D_ON_1 that calculates and the actual duty ratio that is held open of NPN transistor Q1 to another example of the influence of duty ratio D_ON_1.

Figure 17 shows the relation between duty ratio D_ON_1 and the actual duty cycle.

In Figure 17, " course of discharge " refers to utilize dc voltage Vb that the booster converter 12 among Fig. 1 boosts to be provided to the direction of capacitor 13.At described course of discharge, DC current Ib flow through DC power supply B, reactor L1 and NPN transistor Q1 arrive the positive bus-bar of inverter 14,31.When NPN transistor Q1, Q2 during described Dead Time Dt keep to turn-off, the reactor current IL of the reactor L1 that the flows through diode D1 that flows through arrived described positive bus-bar.Therefore, during described Dead Time Dt, NPN transistor Q1 opens.

So the described actual duty cycle of NPN transistor Q1 is greater than the described duty ratio D_ON_1 that calculates as shown in figure 17.

And in Figure 17, " charging direction " refers to that dc voltage is provided to the direction of DC power supply B, and described dc voltage offers booster converter 12 by inverter 14 (or 31) by capacitor 13, and carries out step-down by converter 12.In described charging direction, the flow through positive pole of negative pole, negative busbar, NPN transistor Q2, reactor L1, described positive bus-bar and DC power supply B of DC power supply B of DC current Ib.Then, as mentioned above, when NPN transistor Q1, Q2 kept turn-offing during described Dead Time Dt, the DC current Ib flowed to reactor L1 by diode D2.Therefore, during described Dead Time Dt, NPN transistor Q2 opens.

So the described actual duty cycle of NPN transistor Q1 is less than the described duty ratio D_ON_1 that calculates as shown in figure 17.

When duty ratio D_ON_1 is 1, that is, when described boost operations stops, not carrying out control to the switching of NPN transistor Q1, Q2.Therefore, described actual duty cycle is not influenced by Dead Time Dt, and the duty ratio D_ON_1 that equals to calculate.

Yet, quite approaching as duty ratio D_ON_1 in 1.0 the zone, and described operation carries out the transition to when stopping described boost operations or beginning the state of described boost operations, as shown in figure 17, because the influence of Dead Time Dt, described actual duty cycle changes suddenly, causes the unexpected variation of output voltage V m and DC current Ib.Therefore, may damage DC power supply B and booster converter 12, and shorten its useful life.

Then, present embodiment discloses a kind of voltage conversion device, and when stopping or beginning described boost operations, by reducing the influence of Dead Time Dt, it can reduce the variation of output voltage V m and DC current Ib by the influence that reduces Dead Time Dt.Can notice, motor driving apparatus with the voltage conversion device in the present embodiment has and the identical basic circuit structure of motor driving apparatus among Fig. 1, its difference is that the former comprises controller for transducer 302D, rather than the controller for transducer 302A of control device 30.Therefore, publicly-owned circuit unit is not repeated to describe in detail.

Figure 18 is the functional block diagram according to the controller for transducer 302D of the motor driving apparatus of third embodiment of the invention.

With reference to Figure 18, controller for transducer 302D comprises voltage instruction computing unit 50, converter duty ratio ratio computing unit 52D and converter pwm signal converter unit 54D.

Voltage instruction computing unit 50 is based on torque command value TR1 (or TR2) and motor revolution MRN1 (or MRN2) from external ECU, calculate the optimal value (desired value) of described inverter input voltage, promptly, calculate the voltage instruction value Vdc_com of booster converter 12, and to the described voltage instruction value Vdc_com that calculates of converter duty ratio ratio computing unit 52D output.

Converter duty ratio ratio computing unit 52D calculates the duty ratio D_ON_1 of the NPN transistor Q1 of booster converter 12 based on from the voltage instruction value Vdc_com of voltage instruction computing unit 50 with from the dc voltage Vb of voltage sensor 10 according to expression formula.

Then, converter duty ratio ratio computing unit 52D utilizes the duty ratio D_ON_1 of described calculating to calculate the duty ratio D_ON_2=1-D_ON_1 of NPN transistor Q2.Converter duty ratio ratio computing unit 52D is to the described duty ratio D_ON_1 that calculates of converter pwm signal converter unit 54D output.In addition, converter duty ratio ratio computing unit 52D is to converter pwm signal converter unit 54D output duty cycle ratio DR, and wherein said duty ratio ratio DR is the ratio between duty ratio D_ON_1 and the duty ratio D_ON_2.

Converter duty ratio ratio computing unit 52D calculating voltage command value Vdc_com and from the deviation (Vdc_com-Vm) between the voltage Vm of voltage sensor 20, calculate described duty ratio ratio DR then, make the described deviation that calculates (Vdc_com-Vm) equal zero.

Converter pwm signal converter unit 54D produces signal PWMU or the signal PWMD of the NPN transistor Q1, the Q2 that are used to open/turn-off booster converter 12 based on duty ratio ratio DR and duty ratio D_ON_1 from converter duty ratio ratio computing unit 52D.

About the generation of signal PWMU or signal PWMD, converter pwm signal converter unit 54D stores the relation between duty ratio D_ON_1 and the carrier frequency in advance, as shown in figure 19, thereby makes that carrier frequency fc changes based on this mapping graph.

Figure 19 shows the relation between duty ratio D_ON_1 and the carrier frequency fc.

With reference to Figure 19, carrier frequency fc approaches at duty ratio D_ON_1 to change into carrier frequency fL in the zone of 1.0 (x≤D_ON_1≤1, wherein 0≤x≤1), and it is lower than carrier frequency fH relatively.So, when duty ratio D_ON_1 near 1.0 the time, longer relatively by the long T of control cycle that carrier frequency fc determines.Then, when duty ratio D_ON_1 its approach 1.0 regional the time, Dead Time Dt is relatively low to the ratio of the long T of control cycle, and can reduce the influence of Dead Time Dt.

Consider carrier frequency fL, lower frequency produces effect for the influence that reduces Dead Time Dt.Yet if described frequency is reduced to any frequency in the audiorange, undesirable noise will appear in booster converter 12.Therefore, with described frequency configuration be the optional frequency of its floor level (lowest level) in described audiorange.

Converter pwm signal converter unit 54D uses the carrier frequency fc that is provided with based on duty ratio D_ON_1 to produce signal PWMU or signal PWMD, and to the NPN transistor Q1 of booster converter 12, signal PWMU or the signal PWMD that Q2 exports described generation.

Figure 20 is a flow chart, and it has illustrated the operation of the converter pwm signal converter unit 54D control carrier frequency fc that utilizes described controller for transducer 302D.

With reference to Figure 20, in controller for transducer 302D, in the beginning of a series of voltage transformations operation, converter pwm signal converter unit 54D receives duty ratio D_ON_1 that calculates based on voltage instruction value Vdc_com and dc voltage Vb and the duty ratio ratio DR (step S10) that determines from the described duty ratio D_ON_1 that calculates, D_ON_2 from converter duty ratio ratio computing unit 52D.

Converter pwm signal converter unit 54D is with reference to the mapping graph (step S11) that concerns between duty ratio D_ON_1 shown in Figure 19 and the carrier frequency fc, and based on the described duty ratio D_ON_1 that receives carrier frequency fc (step S12) is set.

When booster converter 12 carried out boost operations, when proceeding to the transition of the state that stops described boost operations and the described boost operations of beginning, the flow chart that converter pwm signal converter unit 54D follows among Figure 20 was provided with carrier frequency fc at every turn.

Figure 21 shows based on the duty ratio D_ON_1 of the voltage transformation in the third embodiment of the invention and the relation between the actual duty cycle.

Can be clear that from Figure 21 when duty ratio D_ON_1 was in it and approaches in 1.0 the zone, for described charging direction and course of discharge, the difference between duty ratio D_ON_1 and the described actual duty cycle was reduced.Like this, when described boost operations began or stops, the influence of Dead Time Dt was reduced.So any unexpected variation in output voltage V m and the DC current Ib is reduced, and can avoid damage to DC power supply B and booster converter 12.

First modified example

Figure 22 is the functional block diagram according to the controller for transducer 302E of the motor driving apparatus of first modified example of third embodiment of the invention.

With reference to Figure 22, controller for transducer 302E comprises voltage instruction computing unit 50E, converter duty ratio ratio computing unit 52E and converter pwm signal converter unit 54E.

Voltage instruction computing unit 50E is based on torque command value TR1 (or TR2) and motor revolution MRN1 (or MRN2) from external ECU, calculate the optimal value (desired value) of described inverter input voltage, promptly, calculate the voltage instruction value Vdc_com of booster converter 12, and to the described voltage instruction value Vdc_com that calculates of converter duty ratio ratio computing unit 52E output.

Then, based on the size of voltage instruction value Vdc_com, voltage instruction computing unit 50E produces pressure-increasning state command signal B_com, and exports the pressure-increasning state command signal B_com of described generation to converter pwm signal converter unit 54E.More specifically, when voltage instruction value Vdc_com was higher than dc voltage Vb, voltage instruction computing unit 50E produced the pressure-increasning state command signal B_com that is used to indicate the beginning boost operations, and exported the signal of described generation to converter pwm signal converter unit 54E.When voltage instruction value Vdc_com becomes when equaling dc voltage Vb, voltage instruction computing unit 50E produces and is used to indicate the pressure-increasning state command signal B_com that stops described boost operations, and exports the signal of described generation to converter pwm signal converter unit 54E.

Based on from the voltage instruction calculated value Vdc_com of voltage instruction computing unit 50E with from the dc voltage Vb of voltage sensor 10, converter duty ratio ratio computing unit 52E calculates the duty ratio D_ON_1 of the NPN transistor Q1 of booster converter 12 according to expression formula (1).

Converter duty ratio ratio computing unit 52E utilizes the described duty ratio D_ON_1 that calculates to calculate the duty ratio D_ON_2=1-D_ON_1 of NPN transistor Q2, and to converter pwm signal converter unit 54E output duty cycle ratio DR, wherein said duty ratio ratio DR is described duty ratio D_ON_1 that calculates and the ratio between the D_ON_2.

Converter duty ratio ratio computing unit 52E calculating voltage command value Vdc_com and from the deviation (Vdc_com-Vm) between the voltage Vm of voltage sensor 20, calculate described duty ratio ratio DR then, make the described deviation that calculates (Vdc_com-Vm) equal zero.

Based on the duty ratio ratio DR from converter duty ratio ratio computing unit 52E, converter pwm signal converter unit 54E produces signal PWMU or the signal PWMD of the NPN transistor Q1, the Q2 that are used to open/turn-off booster converter 12.

About the generation of signal PWMU or PWMD, converter pwm signal converter unit 54E allows carrier frequency fc variable based on the pressure-increasning state command signal B_com from voltage instruction computing unit 50E.

More specifically, as the pressure-increasning state command signal B_com that receives indication beginning boost operations, in the scheduled period that begins from the moment that receives described instruction, converter pwm signal converter unit 54E carrier frequency fc is set to relatively low carrier frequency fL.In addition, indicate the pressure-increasning state command signal B_com that stops described boost operations when receiving, in the scheduled period that begins from the moment that receives described instruction, converter pwm signal converter unit 54E carrier frequency fc is set to relatively low carrier frequency fL.

Figure 23 is a time diagram, and it shows the relation between pressure-increasning state command signal B_com and the carrier frequency fc.

With reference to Figure 23, when the beginning boost operations instruction when moment t1 imports, the carrier frequency fc that converter pwm signal converter unit 54E is in carrier frequency fH is set to relatively low carrier frequency fL, and wherein said carrier frequency fH is the frequency of normal boost operations.Then, in the scheduled period from moment t1 to moment t2, converter pwm signal converter unit 54E is increased to carrier frequency fH with carrier frequency fc gradually.And in the pressure-increasning state after moment t2, converter pwm signal converter unit 54E is fixed on carrier frequency fH with carrier frequency fc.

Subsequently, when the instruction that stops described boost operations when moment t3 imports, in the scheduled period from moment t3 to moment t4, converter pwm signal converter unit 54E is reduced to carrier frequency fL with carrier frequency fc gradually.

Identical at this relatively low frequency f L with carrier frequency fL among Figure 11.According to this modified example, described carrier frequency fc be set to relatively low frequency during be restricted between short-term, to shorten since the carrier frequency reduction produce noise during.

Figure 24 is a flow chart, and it has illustrated the operation of the converter pwm signal converter unit 54E control carrier frequency fc that utilizes controller for transducer 302E.

With reference to Figure 24, in controller for transducer 302E, in a series of beginnings that are used to control the operation of voltage transformation, converter pwm signal converter unit 54E receives the pressure-increasning state command signal B_com (step S20) that produces based on voltage instruction value Vdc_com.

Then, converter pwm signal converter unit 54E determines whether the described pressure-increasning state command signal B_com that receives is the instruction (step S21) of indication beginning boost operations.

When converter pwm signal converter unit 54E has determined to provide the instruction that begins described boost operations, converter unit 54E initialization carrier frequency fc, and be relatively low carrier frequency fL (step S23) with described frequency configuration.Its timer (not shown) that comprises of converter pwm signal converter unit 54E initialization, and begin scheduled period counting (step S24) from the input time t1 of pressure-increasning state command signal B_com, and each described counting increases for the moment, increases predetermined frequency shift amount △ fc (step S25) to carrier frequency fL.

Up to described scheduled period process (corresponding to the YES among the step S26), converter pwm signal converter unit 54E increases the count value (step S27) of described timer, and increases carrier frequency fc simultaneously gradually.

At last, in the described scheduled period process of moment t2, converter pwm signal converter unit 54E is fixed on carrier frequency fH with carrier frequency fc, and wherein said carrier frequency fH is used for normal boost operations.

On the contrary, when converter pwm signal converter unit 54E determined not provide the instruction of the described boost operations of beginning, converter pwm signal converter unit 54E determined whether to have provided the instruction (step S22) that stops described boost operations subsequently.

When converter pwm signal converter unit 54E has determined to provide the instruction that stops described boost operations, the described timer of converter unit 54E initialization (step S28), and begin the scheduled period is counted from the input time t3 of pressure-increasning state command signal B_com.Then, each described counting increases for the moment, deducts predetermined frequency shift amount △ fc (step S29) from carrier frequency fH.

Then, up to described scheduled period process (corresponding to the YES among the step S30), converter pwm signal converter unit 54E increases the count value (step S31) of described timer, and reduces carrier frequency fc simultaneously gradually.So at the moment of described scheduled period process t4, carrier frequency fc is relatively low carrier frequency fL.

Second embodiment

Referring again to the relation between duty ratio D_ON_1 shown in Figure 17 and the described actual duty cycle, for described charging direction and described course of discharge, during described Dead Time Dt, between duty ratio D_ON_1 that determines based on voltage instruction value Vdc_com and described actual duty cycle, there is difference.

At this, about approach the difference of the charging direction in 1.0 the zone at duty ratio D_ON_1, in the moment that carries out the transition to the state (D_ON_1 and actual duty cycle all are 1) that stops described boost operations from the state (D_ON_1 and actual duty cycle are all less than 1) that carries out boost operations, because the influence of aforementioned difference, described actual duty cycle flip-flop, for example, from 0.95 to 1.0.So, output voltage V m and DC current Ib flip-flop, thus DC power supply B and booster converter 12 damaged.

About described course of discharge, in the moment of the state that carries out the transition to the described boost operations of beginning from the state (D_ON_1 and actual duty cycle all are 1) that stops described boost operations, because described difference, in the scheduled period, described actual duty cycle remains on 1.0.D_ON_1 becomes when duty ratio, for example, and 0.95 or more hour, described actual duty cycle begins to be proportional to duty ratio D_ON_1 and changes.Like this, the moment after the described boost operations of beginning, output voltage V m and DC current Ib do not have flip-flop.In other words, Dead Time Dt only has slight influence.

Therefore, in this modified example, only about the described charging direction of output voltage V m and DC current Ib flip-flop, when duty ratio D_ON_1 approached 1.0, carrier frequency fc reduced.

Like this, can reduce the influence of Dead Time Dt, and, the frequency that causes that noise takes place can be reduced by reducing carrier frequency fc.

Figure 25 is the functional block diagram according to the controller for transducer 302F of the motor driving apparatus of second modified example of third embodiment of the invention.

With reference to Figure 25, controller for transducer 302F comprises voltage instruction computing unit 50, converter duty ratio ratio computing unit 52F and converter pwm signal converter unit 54F.

Voltage instruction computing unit 50 is based on torque command value TR1 (or TR2) and motor revolution MRN1 (or MRN2) from external ECU, calculate the voltage instruction value Vdc_com of booster converter 12, and to the described voltage instruction value Vdc_com that calculates of converter duty ratio ratio computing unit 52F output.

Converter duty ratio ratio computing unit 52F is based on from the voltage instruction value Vdc_com of voltage instruction computing unit 50 with from the dc voltage Vb of voltage sensor 10, calculate the duty ratio D_ON_1 of the NPN transistor Q1 of booster converter 12 according to expression formula (1), and to the described duty ratio D_ON_1 that calculates of converter pwm signal converter unit 54F output.Then, converter duty ratio ratio computing unit 52F utilizes the duty ratio D_ON_1 of described calculating to calculate the duty ratio D_ON_2=1-D_ON_1 of NPN transistor Q2, and to converter pwm signal converter unit 54F output duty cycle ratio DR, wherein said duty ratio ratio DR is the ratio between described duty ratio D_ON_1 that calculates and the duty ratio D_ON_2.

Converter duty ratio ratio computing unit 52F calculating voltage command value Vdc_com and from the deviation (Vdc_com-Vm) between the voltage Vm of voltage sensor 20, calculate described duty ratio ratio DR then, make the described deviation that calculates (Vdc_com-Vm) equal zero.

Converter pwm signal converter unit 54F receives duty ratio D_ON_1 and the duty ratio ratio DR from converter duty ratio ratio computing unit 52F, and reactor current IL.Converter pwm signal converter unit 54F receives the value that the current sensor (not shown) of the reactor L1 offer Fig. 1 is recently detected, perhaps by the value of current sensor 10 detected DC current Ib, and as reactor current IL.

Then, it is still mobile with described course of discharge that converter pwm signal converter unit 54F determines that reactor current IL flows with described charging direction, that is, be to control to reduce output voltage V m or to increase output voltage V m.More specifically, based on described reactor current IL at described course of discharge for just being negative condition in described charging direction, converter pwm signal converter unit 54F determines that its reactor current IL that receives is just or negative, thereby determining that reactor current IL flows with described course of discharge still flows with described charging direction.

Then, when determining reactor current IL, converter pwm signal converter unit 54F flows with described charging direction, and when controlling, so converter unit 54F determines that there is considerable influence in Dead Time Dt to the carrier frequency fc that changes based on duty ratio D_ON_1 with reduction output voltage V m.Particularly, converter pwm signal converter unit 54F is in advance with the relation between the form of mapping graph storage duty ratio D_ON_1 and the carrier frequency fc, and based on this mapping graph, changes carrier frequency fc.

Converter pwm signal converter unit 54F uses the carrier frequency fc and the duty ratio ratio DR that are provided with based on duty ratio D_ON_1 to produce signal PWMU or signal PWMD, and to NPN transistor Q1, the Q2 of booster converter 12 export described generation signal PWMU or signal PWMD.

On the contrary, when determining reactor current IL, converter pwm signal converter unit 54F flows with described course of discharge, and when controlling with increase output voltage V m, so, converter unit 54F determines, no matter duty ratio D_ON_1 how, Dead Time Dt only has less influence for carrier frequency fc being fixed as the carrier frequency fH that is used for normal boost operations.Then, converter pwm signal converter unit 54F use carrier frequency fH and duty ratio ratio DR produce signal PWMU or the signal PWMD of the NPN transistor Q1, the Q2 that are used to open/turn-off booster converter 12, and to the NPN transistor Q1 of booster converter 12, signal PWMU or the PWMD that Q2 exports described generation.

Figure 26 is a flow chart, and it has illustrated the operation of the converter pwm signal converter unit 54F control carrier frequency fc that utilizes controller for transducer 302F.

With reference to Figure 26, in controller for transducer 302F, in a series of beginnings that are used to control the operation of voltage transformation, converter pwm signal converter unit 54F receives the determined duty ratio ratio of duty ratio D_ON_1, the D_ON_2 DR that calculates by based on voltage instruction value Vdc_com and dc voltage Vb from converter duty ratio ratio computing unit 52F.In addition, converter pwm signal converter unit 54F receives the reactor current IL (step S40) that offers reactor L1 from the current sensor (not shown).

Converter pwm signal converter unit 54F determines whether whether reactor current IL flows with described charging direction, promptly control to reduce output voltage V m (step S41).

When converter pwm signal converter unit 54F determined that reactor current IL flows with described charging direction, converter unit 54F received the duty ratio D_ON_1 that calculates (step S42) from converter duty ratio ratio computing unit 52F.

Converter pwm signal converter unit 54F is with reference to the mapping graph (step S43) of the relation between duty ratio D_ON_1 and the carrier frequency fc that shows among Figure 19, and based on the duty ratio D_ON_1 that it receives carrier frequency fc (step S44) is set.

On the contrary, when converter pwm signal converter unit 54F determined that reactor current IL flows with described course of discharge, converter unit 54F carrier frequency fc was set to be used for the carrier frequency fH (step S45) of normal boost operations.

Figure 27 show according to second modified example of third embodiment of the invention based on the duty ratio D_ON_1 of voltage transformation and the relation between the actual duty cycle.

Can be clear that from Figure 27, in duty ratio D_ON_1 approaches 1.0 zone,, reduce the difference between duty ratio D_ON_1 and the described actual duty cycle only for described charging direction.Like this, can effectively prevent to be subjected to a great extent that Dead Time Dt influences, about the output voltage V m of described charging direction and the unexpected variation of DC current Ib, and, can reduce the frequency that noise takes place.

It may be noted that to described first embodiment in utilize controller for transducer 302A similar to the voltage transformation that 302C carried out, the controller for transducer 302D of control device 30 is in fact also carried out by CPU to the control of voltage transformation that 302F carried out.Described CPU reads each the program of step that has comprised flow chart among Figure 20,24 and 26 from ROM, carry out the described program that reads, and follow flow chart shown in Figure 20,24 and 26 each control described voltage transformation.Therefore, described ROM is corresponding to the computer that has write down program thereon (CPU) readable medium recording program performing, and wherein said program has comprised each step of flow chart shown in Figure 20,24 and 26.

Although the present invention is explained and describes, can know clearly that still these describe the effect of only playing explanation and giving an example, as the restriction to invention, the spirit and scope of the present invention are not only limited by claims.

Claims (6)

1. voltage conversion device that changes to the input voltage of inverter (14) changeably, described voltage conversion device comprises:

Voltage changer (12), it comprises upper arm and underarm, and carries out voltage transformation between power supply (B) and described inverter (14) by the switching of described upper arm and described underarm; And

Control device (30), it controls described voltage changer (12), thereby reduces the influence of the Dead Time of described voltage changer (12) to the duty ratio of described switching, wherein,

By described voltage changer, (12) voltage instruction value of the described voltage transformation that carries out is greater than under the situation of supply voltage less than predetermined voltage, described control device, (30) recently control described voltage changer by utilizing first duty ratio and second duty ratio that described duty is set, (12), wherein, described first duty ratio is the duty ratio when the voltage of described predetermined voltage is at least described voltage instruction value, described second duty ratio is the duty ratio when described supply voltage is described voltage instruction value

Wherein, describedly utilize first duty ratio and second duty ratio that described duty ratio is set further to be: by than between described first duty ratio and described second duty ratio, switching described duty ratio being set with predetermined.

2. voltage conversion device that changes to the input voltage of inverter (14) changeably, described voltage conversion device comprises:

Voltage changer (12), it comprises upper arm and underarm, and carries out voltage transformation between power supply (B) and described inverter (14) by the switching of described upper arm and described underarm; And

Control device (30), it controls described voltage changer (12), thereby reduces the influence of the Dead Time of described voltage changer (12) to the duty ratio of described switching, wherein,

Produce at the DC electric current that has described power supply (B) under the situation of possibility of surge, described control device (30) is recently controlled described voltage changer (12) by utilizing first duty ratio and second duty ratio that described duty is set, wherein, described first duty ratio is the duty ratio when the voltage of predetermined voltage is at least voltage instruction value, described second duty ratio is the duty ratio when supply voltage is described voltage instruction value

Wherein, describedly utilize first duty ratio and second duty ratio that described duty ratio is set further to be: by than between described first duty ratio and described second duty ratio, switching described duty ratio being set with predetermined.

3. voltage conversion device that changes to the input voltage of inverter (14) changeably, described voltage conversion device comprises:

Voltage changer (12), it comprise in each cycle with the first duty ratio time corresponding section in the upper arm that is unlocked, and in each cycle with the second duty ratio time corresponding section in the underarm that is unlocked, and carry out voltage transformation between power supply (B) and described inverter (14) by the switching of described upper arm and described underarm, wherein, described second duty ratio equals to deduct the value that described first duty ratio obtains from 1; And

Control device (30), when described first duty ratio of calculating based on the voltage instruction value of the described voltage transformation that is undertaken by described voltage changer (12) is influenced by the Dead Time of described upper arm and described underarm, it is set to predetermined than switching the switching of controlling described upper arm and described underarm between the longest duty ratio that keeps described upper arm to open in the effective duty ratio of maximum with in control cycle is long by described first duty ratio, wherein

By determining the effective duty ratio of described maximum divided by described control cycle length, wherein, determine that by from described control cycle is long, deducting described Dead Time described effective control cycle is long with effective control cycle length.

4. an execution is to the method for the voltage transformation control of voltage conversion device,

Described voltage conversion device has voltage changer (12), it comprise in each cycle with the first duty ratio time corresponding section in the upper arm that is unlocked, and in each cycle with the second duty ratio time corresponding section in the underarm that is unlocked, and carry out voltage transformation between power supply (B) and described inverter (14) by the switching of described upper arm and described underarm, wherein, described second duty ratio equals to deduct the value that described first duty ratio obtains from 1, and

Described method comprises:

The first step is calculated described first duty ratio based on the voltage instruction value of described voltage transformation;

In second step, determine whether described first duty ratio that calculates is influenced by the Dead Time of described upper arm and described underarm; And

The 3rd step, when definite described first duty ratio is influenced by described Dead Time, the switching that described first duty is recently controlled described upper arm and described underarm is set by the longest duty ratio of utilizing maximum effectively duty ratio and in control cycle is long, keep described upper arm to open;

Wherein, described the 3rd step is by being provided with described first duty ratio with predetermined than switching between effective duty ratio of described maximum and the longest described duty ratio.

5. method according to claim 4, wherein,

Described second step comprises:

First substep utilizes described Dead Time to calculate the effective duty ratio of described maximum;

Second substep determines that whether described first duty ratio that calculates is greater than the effective duty ratio of described maximum and less than the longest described duty ratio that keeps described upper arm to open in described control cycle is long;

The 3rd substep when described first duty ratio during greater than the effective duty ratio of described maximum and less than described the longest duty ratio, determines that described first duty ratio is influenced by described Dead Time; And

The 4th substep, when described first duty ratio is at most the effective duty ratio of described maximum or during for described the longest duty ratio, determines that described first duty ratio is not influenced by described Dead Time, and,

By determining the effective duty ratio of described maximum divided by described control cycle length, wherein, determine that by from described control cycle is long, deducting described Dead Time described effective control cycle is long with effective control cycle length.

6. method according to claim 4, wherein,

Described second step comprises:

First substep detects the DC electric current of described power supply (B);

Second substep, whether the slope of output waveform of DC electric current of described detection of determining described power supply (B) is greater than predetermined threshold;

The 3rd substep when the described slope of the described output waveform of the described DC electric current of described power supply (B) during greater than described predetermined threshold, determines that described first duty ratio is influenced by described Dead Time; And

The 4th substep when the described slope of the described output waveform of the described DC electric current of described power supply (B) is at most described predetermined threshold, determines that described first duty ratio is not influenced by described Dead Time.

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