JP4138423B2 - Power output device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a power output apparatus.
[0002]
[Prior art]
Conventionally, power provided with a capacitor connected to the positive and negative buses of the inverter circuit that applies three-phase alternating current to the motor, and a DC power source connected to the positive or negative bus of the inverter circuit and the neutral point of the motor An output device has been proposed (for example, JP-A-10-337047 (Patent Document 1), JP-A-11-178114 (Patent Document 2), etc.). In this apparatus, a circuit composed of a coil of each phase of an electric motor and a switching element of an inverter circuit is boosted and stored in a capacitor by boosting the voltage of a DC power source, and the motor is driven by regarding the stored capacitor as a DC power source. The stored voltage of the capacitor is adjusted by controlling the DC component of the three-phase AC applied to the motor, that is, by controlling the neutral point potential of the motor.
[0003]
By the way, as a power output device that improves the use efficiency of the voltage of the DC power supply and improves the output of the motor, the third harmonic is superimposed on the three-phase voltage command (modulated wave) in the PWM (pulse width modulation) control. There has been proposed one that applies a three-phase alternating current to a motor based on a comparison between an object and a triangular wave that is a carrier wave (for example, JP-A-10-210756 (Patent Document 3)). When the third harmonic is superimposed on the modulated wave, the amplitude of the modulated wave can be reduced without lowering the output of the electric motor, so that the amplitude of the reduced modulated wave can be increased, and as a result, the electric motor The maximum output can be improved.
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 10-337047
[Patent Document 2]
JP-A-11-178114
[Patent Document 3]
Japanese Patent Laid-Open No. 10-210756
[0005]
[Problems to be solved by the invention]
However, when driving the motor using the stored voltage of the capacitor, if the third harmonic is superimposed, the DC component of the three-phase AC generated by PWM modulation (the potential at the neutral point of the motor) will vibrate Therefore, the stored voltage of the capacitor cannot be maintained at the target voltage and vibrates. As a result, torque ripple occurs in the electric motor that is driven using the stored voltage of the capacitor.
[0006]
Further, the electric motor can be driven by switching control of the switching element of the inverter circuit using the detection result by the current sensor attached to each phase of the three-phase coil. However, at this time, a current sensor must be attached to at least two of the phases of the three-phase coil. When a plurality of such three-phase coils are provided, a large number of current sensors are required, and the cost of the apparatus is increased. For this reason, it is preferable to reduce the cost by reducing the number of current sensors provided in the power output device as much as possible.
[0007]
The power output device of the present invention is to solve these problems, and to ensure that the required power output is secured and to use the first power source more efficiently to output higher power. I will. The power output apparatus of the present invention can output higher power using the first power source more efficiently without affecting the voltage of the first power source as the chargeable / dischargeable power storage means. One of the purposes.
[0008]
Another object of the power output apparatus of the present invention is to reduce the number of current detection means used for switching control of an inverter circuit, thereby realizing cost reduction of the apparatus.
[0009]
[Means for solving the problems and their functions and effects]
The power output apparatus of the present invention employs the following means in order to achieve at least a part of the above object.
[0019]
  The present inventionMovementForce output device
  Two star connection coils having the same phase, two inverter circuits capable of supplying polyphase AC power to each of the two star connection coils by sharing the positive and negative buses, and the positive electrode A first power source connected to the bus bar and the negative electrode bus bar, a second power source connected between neutral points of the two star connection coils, and currents in phase to the corresponding two star connection coils And a control means for controlling the switching of the switching elements of the two inverter circuits so that the same power is output by applying
  An addition current that is commonly used for each phase of one star connection coil and the other two phases of the star connection coil, and detects an addition current of each current flowing through the two coils. Detection means;
  Neutral point current detection means for detecting a current flowing between the neutral points;
  The added current detected by the added current detecting means used for controlling the control meansAnd the neutral point current detected by the neutral point current detection meansPhase current calculating means for calculating a phase current flowing through each phase of the two star-shaped connection coils;
  It is a summary to provide.
[0020]
  This inventionMovementIn the force output device, each phase of one star connection coil and each other phase of the other star connection coil that can output the same power by receiving a current of the same phase are shared by two coils of the same phase. The added current detecting means attached to the two current detectors detects the added current of each current flowing through the two coils, and the phase current calculating means detects each of the two star connection coils from the added current detected by the added current detecting means. Calculate the phase current flowing through the phase. Therefore, since it is not necessary to provide a current sensor for each phase of the two star connection coils in order to detect the phase current used for switching control of the switching element of the inverter circuit, the number of current sensors can be reduced. it can. As a result, cost reduction of the apparatus can be realized.
[0021]
  thisThe present inventionMovementForce output deviceThenAnd a neutral point current detection means for detecting a current flowing between the neutral points, wherein the phase current calculation means includes the addition current detected by the addition current detection means and the neutral point current detection means. Means for calculating each phase current based on the current between the neutral points detected byThe Also,Thisbook ofinventionMovementIn the force output device, the phase current calculation means calculates a value obtained by halving the addition current detected by the addition current detection means and a neutral point current detected by the neutral point current detection means. It may be a means for calculating each phase current based on a value divided by the number of phases of the star connection coil.
[0022]
  In addition, the present inventionMovementIn the force output device, the two star connection coils may be provided corresponding to one rotor to constitute one electric motor.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
  Next, an embodiment of the present invention will be described. FIG. 1 illustrates the present invention.Basic formIt is a block diagram which shows the outline of a structure of the power output device 20 which is.Basic formAs shown in the figure, the power output apparatus 20 includes a double-winding motor (hereinafter referred to as a 2Y motor) 22 having two three-phase coils 24 and 26 Y-connected, and two three-phase coils 24 and 26. Two inverter circuits 30 and 32 that are connected to each other and share the positive electrode bus 34 and the negative electrode bus 36, a capacitor 38 that is connected to the positive electrode bus 34 and the negative electrode bus 36, and two three-phase coils 24 and 26 of the 2Y motor 22. A DC power supply 40 provided between the neutral points and an electronic control unit 50 for controlling the entire apparatus.
[0024]
  FIG. 2 is an explanatory diagram illustrating the relationship between the two three-phase coils 24 and 26 of the 2Y motor 22. In the 2Y motor 22, for example, the winding angle of a rotor with a permanent magnet attached to the outer surface and two three-phase coils 24 and 26 having the same winding specifications as illustrated in FIG. It is composed of a wound stator and has the same structure as that of a normal synchronous generator motor capable of generating power except that two three-phase coils 24 and 26 are wound. In order to drive the 2Y motor 22, the inverter circuits 30 and 32 may be controlled so that the inverter circuits 30 and 32 apply the same-phase three-phase alternating current to the three-phase coils 24 and 26, respectively. The rotational axis of the 2Y motor 22 isBasic formThe power output device 20 is an output shaft, and power is output from the rotating shaft.Basic formSince the 2Y motor 22 is configured as a generator motor as described above, power can be generated by the 2Y motor 22 by inputting power to the rotating shaft of the 2Y motor 22.
[0025]
The inverter circuits 30 and 32 are each composed of six transistors T11 to T16 and T21 to T26 and six diodes D11 to D16 and D21 to D26. The six transistors T11 to T16 and T21 to T26 are arranged in pairs so as to be on the source side and the sink side with respect to the positive electrode bus 34 and the negative electrode bus 36, respectively. Each of phase coils 24 and 26 (U1V1W1) and (U2V2W2) is connected. Therefore, if the on-time ratios of the transistors T11 to T16 and T21 to T26 that are paired in a state where a voltage is applied to the positive electrode bus 34 and the negative electrode bus 36 are controlled in the same phase, the three-phase coil 24 of the 2Y motor 22 is controlled. , 26 to form a rotating magnetic field, and the 2Y motor 22 can be driven to rotate.
[0026]
The electronic control unit 50 is configured as a microprocessor centered on a CPU 52, and includes a ROM 54 that stores a processing program, a RAM 56 that temporarily stores data, and an input / output port (not shown). The electronic control unit 50 includes phase currents Iu1, Iv1, Iw1, Iu2, Iv2, and Iw2 from current sensors 61 to 66 attached to U1V1W1 and U2V2W2 phases of the three-phase coils 24 and 26 of the 2Y motor 22, respectively. The current between the neutral points Io from the current sensor 67 attached between the neutral points of the 2Y motor 22 and the rotation angle of the rotor of the 2Y motor 22 from the rotation angle sensor 68 attached to the rotation shaft of the 2Y motor 22. θ, the voltage Vc between the terminals of the capacitor 38 from the voltage sensor 70 attached to the capacitor 38, the voltage Vb between the terminals of the DC power supply 40 from the voltage sensor 72 attached to the DC power supply 40, and a command value related to driving of the 2Y motor 22 Etc. are input through the input port. Here, any one of the current sensors 61 to 63 and the current sensors 64 to 66 may be omitted, or any one of them may be used as a sensor dedicated to abnormality detection. From the electronic control unit 50, control signals for performing switching control of the transistors T11 to T16 and T21 to T26 of the inverter circuits 30 and 32 are output via an output port.
[0027]
  Then configured like thisBasic formThe operation principle of the power output apparatus 20 will be described. 3 shows the current flow in the state where the neutral point of the three-phase coil 24, the neutral point of the three-phase coil 26, and the potential difference V012 is smaller than the voltage Vb of the DC power supply 40, and the three-phase coils 24 and 26 of the 2Y motor 22. FIG. 6 is an explanatory diagram focusing on the u-phase leakage inductance. Now, whether or not the transistor T12 of the inverter circuit 30 is on in the state where the potential difference V012 between the neutral point of the three-phase coil 24 and the neutral point of the three-phase coil 26 is smaller than the voltage Vb of the DC power supply 40, or the transistor of the inverter circuit 32 Consider a state in which T21 is on. In this case, a short circuit indicated by a solid arrow in FIG. 3A or FIG. 3B is formed, and the u-phase of the three-phase coils 24 and 26 of the 2Y motor 22 functions as a reactor. In this state, when the transistor T12 of the inverter circuit 30 is turned off and the transistor T21 of the inverter circuit 32 is turned off, the energy stored in the u-phase of the three-phase coil functioning as a reactor is indicated by a solid arrow in FIG. Is stored in the capacitor 38 by the charging circuit shown in FIG. Therefore, this circuit can be regarded as a capacitor charging circuit that stores the energy of the DC power supply 40 in the capacitor 38. Since this capacitor charging circuit has the same configuration as the step-up chopper circuit, the inter-terminal voltage Vc of the capacitor 38 can be freely operated higher than the voltage Vb of the DC power supply 40. Since the vw phase of the three-phase coils 24 and 26 of the 2Y motor 22 can also be regarded as a capacitor charging circuit like the u-phase, the potential difference between the neutral point of the three-phase coil 24 and the neutral point of the three-phase coil 26. The capacitor 38 is charged by the DC power supply 40 by setting V012 to be lower than the voltage Vb of the DC power supply 40 and turning on and off the transistors T12, T14, T16 of the inverter circuit 30 and the transistors T21, T23, T25 of the inverter circuit 32. be able to.
[0028]
FIG. 4 shows the current flow in a state where the potential difference V012 between the neutral point of the three-phase coil 24 and the neutral point of the three-phase coil 26 is larger than the voltage Vb of the DC power supply 40, and the three-phase coils 24 and 26 of the 2Y motor 22. It is explanatory drawing paying attention and paying attention to the leakage inductance of u phase. This time, with the potential difference V012 between the neutral point of the three-phase coil 24 and the neutral point of the three-phase coil 26 larger than the voltage Vb of the DC power supply 40, the transistor T12 of the inverter circuit 30 is turned on, the transistor T12 is turned off, and the inverter Consider a state in which transistor T21 of circuit 32 is off and transistor T22 is on. In this case, a charging circuit indicated by a solid arrow in FIG. 4A is formed, and the DC power supply 40 is charged using the inter-terminal voltage Vc of the capacitor 38. At this time, the u-phase of the three-phase coils 24 and 26 of the 2Y motor 22 functions as a reactor as described above. When the transistor T11 of the inverter circuit 30 is turned off or the transistor T22 of the inverter circuit 32 is turned off from this state, the energy stored in the u-phase of the three-phase coil functioning as the reactor is as shown in FIG. (C) The DC power supply 40 is charged by a charging circuit indicated by a solid solid arrow. Therefore, this circuit can be regarded as a DC power supply charging circuit that stores the energy of the capacitor 38 in the DC power supply 40. Since the vw phase of the three-phase coils 24 and 26 of the 2Y motor 22 can also be regarded as a DC power supply charging circuit like the u-phase, the neutral point of the three-phase coil 24 and the neutral point of the three-phase coil 26 The DC power supply 40 can be charged by the capacitor 38 by making the potential difference V012 larger than the voltage Vb of the DC power supply 40 and turning on and off the transistors T11 to T16 of the inverter circuit 30 and the transistors T21 to T26 of the inverter circuit 32. .
[0029]
  in this way,Basic formIn the power output apparatus 20, the capacitor 38 can be charged by the DC power supply 40, and conversely, the DC power supply 40 can be charged by the capacitor 38, so that the terminal voltage Vc of the capacitor 38 can be controlled to a desired value. it can. When a potential difference is generated between the terminals of the capacitor 38, a DC power source by the capacitor 38 is connected to the positive bus 34 and the negative bus 36 of the inverter circuits 30 and 32, and the inter-terminal voltage Vc of the capacitor 38 becomes the inverter input voltage. Since it acts as Vi, the 2Y motor 22 can be driven and controlled by switching control of the transistors T11 to T16 and T21 to T26 of the inverter circuits 30 and 32. At this time, the potentials Vu1, Vv1, and Vw1 of the three-phase AC applied to the three-phase coil 24 can be freely set within the range of the inverter input voltage Vi by switching control of the transistors T11 to T16 of the inverter circuit 30. The potentials Vu2, Vv2, and Vw2 of the three-phase alternating current applied to the phase coil 26 can also be freely set within the range of the inverter input voltage Vi by switching control of the transistors T21 to T26 of the inverter circuit 32. The neutral point potential V01 of the three-phase coil 24 and the neutral point potential V02 of the three-phase coil 26 can be freely manipulated. FIG. 5 shows each phase of the three-phase coil 24 when the difference between the neutral point potential V01 of the three-phase coil 24 and the neutral point potential V02 of the three-phase coil 26 becomes the voltage Vb of the DC power supply 40. FIG. 5A shows an example of waveforms of potentials Vu1, Vv1, and Vw1 (FIG. 5A) and waveforms of potentials Vu2, Vv2, and Vw2 of each phase of the three-phase coil 26 (FIG. 5B). In the figure, Vx is the median value (Vi / 2) of the inverter input voltage Vi. Therefore, the capacitor 38 is charged by operating so that the potential difference V012 between the neutral points of the three-phase coils 24 and 26 of the 2Y motor 22 is lower than the voltage Vb of the DC power supply 40, or conversely. The DC power supply 40 can be charged by operating so that the potential difference V012 between the neutral points becomes higher than the voltage Vb of the DC power supply 40. The charging current of the capacitor 38 and the charging current of the DC power supply 40 can be controlled by raising and lowering the potential difference V012 between the neutral points of the three-phase coils 24 and 26.
[0030]
  next,Basic formThe drive control of the power output apparatus 20 will be described. FIG.Basic formIt is a control block diagram which shows the drive control performed with the electronic control unit 50 of the motive power output device 20 as a control block. As shown in the figure, the rotor of the 2Y motor 22 in which the respective phase currents Iu1, Iv1, Iw1, Iu2, Iv2, Iw2 (motor currents) detected by the current sensors 61-63, 64-66 are detected by the rotation angle sensor 68. A three-phase two-phase conversion unit M1 that performs three-phase two-phase (dq axis) conversion using a rotation angle θ (rotational position) of the current, and a current command value Id * that is input as one of command values related to driving of the 2Y motor 22 , Iq * (dq axis current command) and the subtractor M2 for calculating the deviations ΔId, ΔIq between the currents Id, Iq converted by the three-phase two-phase conversion unit M1, and the deviations ΔId, ΔIq The PI control unit M3 that calculates the voltage operation amounts Vd and Vq for adjusting the motor drive current using the PI gain, and the rotation angle θ of the rotor of the 2Y motor 22 detected by the rotation angle sensor 68 with the voltage operation amounts Vd and Vq. The Two-phase (dq axis) three-phase conversion to calculate each phase potential Vu1, Vv1, Vw1, Vu2, Vv2, Vw2, and the capacitor voltage Vc and voltage detected by the voltage sensor 70 Based on the battery voltage Vb detected by the sensor 72 and the target voltage Vc * of the capacitor 38 input as one of the command values related to the driving of the 2Y motor 22, the potential difference V012 between the neutral points for adjusting the capacitor voltage (three Two-phase three-phase three-phase coil 24 using a capacitor voltage control unit M5 for calculating the neutral point potential V01 of the phase coil 24 and the neutral point potential V02) of the three-phase coil 126 and the rotation angle θ detected by the rotation angle sensor 68. Third harmonics (each phase potential Vu1, Vv1, Vw1, Vu2 synchronized with each phase potential Vu1, Vv1, Vw1, Vu2, Vv2, Vw2 obtained by the phase converter M4 , Vv2, Vw2, and a third harmonic generation unit M6 that generates a sine wave having a frequency three times the frequency of Vv2, Vw2, and each phase potential Vu1, obtained by the third harmonic and the two-phase three-phase conversion unit M4 An adder M7 that obtains a modulation signal by adding Vv1, Vw1, Vu2, Vv2, Vw2 and the potential difference V012 between the neutral points obtained by the capacitor voltage control unit M5, and a modulation signal obtained by the adder M7 A PWM signal calculation unit M8 that calculates a PWM signal by comparing with a triangular wave as a carrier wave is provided. In the control block, the block for the three-phase coil 24 and the block for the three-phase coil 26 are described as the same block. The three-phase two-phase conversion unit M1 to the two-phase three-phase conversion unit M4, the adder M7, and the PWM signal calculation unit M8 include the phase potentials Vu1, Vv1, Vw1, Vu2, Vv2 obtained by the two-phase three-phase conversion unit M4. , Vw2 is the same as the normal motor control except that the potential difference V012 between the neutral points and the third harmonic are added. The processing for calculating the potential difference V012 between the neutral points in the capacitor voltage control unit M5 is, for example, calculating a deviation ΔVc between the target voltage Vc * of the capacitor 38 and the capacitor voltage Vc, and using the PI gain for this deviation ΔVc. The battery voltage command for adjusting the capacitor voltage (current command between neutral points) Io * is calculated, and the potential difference V012 between the neutral points is calculated based on the battery current command Io * and the battery voltage Vb. be able to.
[0031]
FIG. 7 is an explanatory diagram for explaining how the modulation signals respectively corresponding to the three-phase coils 24 and 26 of the 2Y motor 22 are obtained by superimposing the third harmonic. In FIG. 7, only the modulation signals Vu1 * and Vu2 * corresponding to the u phase of the three-phase coils 24 and 26 are shown, but the modulation signals Vv1 *, Vv2 *, Vw1 *, corresponding to the v phase and the w phase are shown. Vw2 * is the same as the modulation signals Vv1 * and Vu2 * corresponding to the u phase, only with a different phase. Now, the modulation waves Vu1 and Vu2 (the following equations (1) and (2)) corresponding to the three-phase coils 24 and 26 (modulation waves before superimposing the third harmonic) 3 of the frequency of the modulation waves Vu1 and Vu2. Consider a case in which modulation signals Vu1 * and Vu2 * (following equations (5) and (6)) are generated by superimposing a third harmonic V3 having the double frequency (following equation (3)). Here, Vc represents the voltage of the capacitor 28, and V0 represents the command value of the neutral point potential of the three-phase coils 24 and 26.
Vu1 = (2 / √3) Vc · sinθ + V0 (1)
Vu2 = (2 / √3) Vc · sinθ−V0 (2)
V3 = (1 / 3√3) Vc · sin3θ (3)
Vu1 * = (2√3) Vc (sinθ + sin3θ / 6) + V0 (5)
Vu2 * = (2√3) Vc (sinθ + sin3θ / 6) −V0 (6)
[0032]
In this case, the modulation signals Vu1 and Vu2 (see FIG. 7A) before superimposing the third harmonic and the modulation signals Vu1 * and Vu2 * after superimposing the third harmonic (see FIG. 7B). ), The amplitudes of the modulation signals Vu1 * and Vu2 * after superimposing the third harmonic are modulated signals Vu1, before superimposing the third harmonic even when the same torque is output, as shown in the figure. Since the amplitude can be 3√3 / 2 times the amplitude of Vu2, the modulation signals Vu1 * and Vu2 * after superimposing the third harmonic can efficiently use the terminal voltage Vc of the capacitor 38. I understand. Note that the amplitude of the third harmonic is set to a value suitable for reducing the amplitude of the modulation signals Vu1 * and Vu2 *.
[0033]
As described above, the voltage Vc of the capacitor 38 can be controlled by the potential difference V012 between the neutral points of the three-phase coils 24 and 26. Therefore, if the potential difference V012 between the neutral points can be maintained, the third harmonic is added to the modulated wave. Even if superimposed, the voltage Vc of the capacitor 38 does not vibrate. That is, the power output by the current applied to the three-phase coil 24 and the power output by the in-phase current applied to the three-phase coil 26 are the same (the phase potentials Vu1, Vv1, Vw1 of the three-phase coil 24). If the third harmonics having the same frequency and amplitude are superimposed on each other, the amplitude and frequency of each phase potential Vu2, Vv2, and Vw2 of the three-phase coil 26 are the same). As shown in FIG. 7, since the potential difference V012 between the neutral points is maintained in a constant state, the voltage Vc of the capacitor 38 does not oscillate. The third harmonics are superimposed on the phase potentials Vu1, Vv1, Vw1, Vu2, Vv2, and Vw2, thereby reducing the amplitude of the modulation signal obtained by the adder M7 with the same torque (√3 / 2 times). Therefore, the amplitude of the modulation signal can be set larger (maximum (2 / √3) times larger) by the decrease, and the output from the 2Y motor 22 can be improved by about 15% at the maximum.
[0034]
  Explained aboveBasic formAccording to the motive power output device 20, the phase potentials Vu1, Vv1, Vw1 having the same amplitude and frequency obtained by the two-phase three-phase converter M4 corresponding to each of the three-phase coils 24, 26, and Since the third harmonics having the same amplitude and frequency are superimposed on the phase potentials Vu2, Vv2, and Vw2 (modulation signals), the transistors T11 to T16 and T21 to T26 of the inverter circuits 30 and 32 are switched. The amplitude maximum value of the modulation signal can be reduced while holding the potential difference V012 between the neutral points of the three-phase coils 24 and 26, that is, holding the voltage Vc of the capacitor 38 at the target voltage Vc *. As a result, the upper limit of the torque output from the 2Y motor 22 can be further improved without causing the voltage Vc of the capacitor 38 to vibrate.
[0035]
  Basic formIn the power output apparatus 20, the superposition of the third harmonic on the modulation wave in the case of driving and controlling the 2Y motor 22 having the three-phase coil 24 and the three-phase coil 26 is considered. It may be applied to drive control of a first motor having one first three-phase coil and a second motor having the other second three-phase coil. However, by superimposing the third harmonicBasic formThe same effect as that of the power output device 20 can be obtained when the first and second motors are controlled with the same output, that is, the phase potentials Vu1, Vv1, Vw1 (3 of the first three-phase coils). Only when the amplitude and frequency of the modulated wave before superimposing the second harmonic are the same as the amplitude and frequency of each phase potential Vu2, Vv2, Vw2 (modulated wave before superimposing the third harmonic) of the second three-phase coil. It is done.
[0036]
  Next, the present inventionThe fruitThe power output apparatus 120 of the embodiment will be described. Figure 8, RealIt is a block diagram which shows the outline of a structure of the power output device 120 of embodiment.. FruitAs shown in the figure, the power output apparatus 120 of the embodiment includes a double-winding motor (hereinafter referred to as a 2Y motor) 122 having two three-phase coils 124 and 126 Y-connected, and two three-phase coils 124, 126, two inverter circuits 130 and 132 that share the positive bus 134 and the negative bus 136, a capacitor 138 connected to the positive bus 134 and the negative bus 136, and the two three-phase coils 124 of the 2Y motor 122, respectively. , 126, a DC power supply 140 provided between neutral points, a current sensor 161 attached to a collective portion in which the u-phase of the three-phase coil 124 and the u-phase of the three-phase coil 126 are gathered, and the three-phase coil A current sensor 162 attached to a collecting portion where 124 v-phase and three-phase coil v-phase are gathered, and attached between neutral points of the three-phase coils 124 and 126 It includes a flow sensor 167, and an electronic control unit 150 that controls the entire apparatus. in this way, RealThe power output apparatus 120 of the embodiment is replaced with the current sensors 61 to 66 of the power output apparatus 20 of the embodiment, and a current sensor 161 shared by the u phase of the three-phase coil 124 and the u phase of the three-phase coil 126, and three The hardware configuration is the same as that of the power output apparatus 20 of the embodiment except that a common current sensor 162 is provided for the v-phase of the phase coil 124 and the v-phase of the three-phase coil 126. Therefore, RealOf the configuration of the power output device 120 of the embodiment, the configuration corresponding to the power output device 20 of the embodiment is denoted by the reference numeral 100, and the description thereof is omitted.
[0037]
The current sensors 161 and 162 are, for example, Hall current sensors or servo magnetic current sensors, and detect an added current obtained by adding two currents flowing through the same phase of the corresponding two three-phase coils 124 and 126 as a current signal. In the embodiment, the common current sensors 161 and 162 are attached to the two u-phase aggregate portions and the two v-phase aggregate portions of the corresponding three-phase coils 124 and 126, respectively. It is good also as what attaches a common current sensor also to the gathering part which gathered the phase.
[0038]
  Configured in this wayFruitThe operation of the power output device 120 of the embodiment, in particular, the phase currents Iu1, Iv1, Iw1, Iu2, Iv2 flowing through the phases of the three-phase coils 124, 126 using the detection results of the current sensors 161, 162 and the current sensor 167. , Iw2 is calculated, and the operation when the 2Y motor 122 is driven and controlled using the calculation result will be described.
[0039]
FIG. 9 is a diagram illustrating an example of the u-phase addition current Iu (= Iu1 + Iu2) detected by the current sensor 161. Now, when the power output from the 2Y motor 22 by the current applied to the three-phase coil 124 of the 2Y motor 122 and the power output from the 2Y motor 22 by the current applied to the three-phase coil 126 are the same, that is, three Consider a case where a phase current having the same amplitude and frequency is applied to each phase of the phase coil 124 and each phase of the three-phase coil 126. The u-phase addition current Iu detected by the current sensor 161 is obtained by adding the u-phase current Iu1 of the three-phase coil 124 and the u-phase current Iu2 of the three-phase coil 126 as shown in FIG. The v-phase addition current Iv detected by the current sensor 162 and the w-phase addition current Iw calculated based on the detection results of the current sensors 161 and 162 are the same except that the phases are different. Therefore, the u-phase addition current Iu detected by the current sensor 161, the v-phase addition current Iv detected by the current sensor 162, and the w-phase addition current Iw calculated based on the detection results of the current sensors 161 and 162 are: It can be shown by a formula. Here, Io is a zero-phase current (current between neutral points), and Io / 3 is one phase of the zero-phase current. I is the amplitude of each phase current Iu1, Iv1, Iw1, Iu2, Iv2, Iw2.
[0040]
Iu = Iu1 + Iu2 = (I · sin θ−Io / 3) + (I · sin θ + Io / 3)
= 2 ・ I ・ sinθ (7)
Iv = Iv1 + Iv2 = (I · sin (θ−2 / 3π) −Io / 3) + (I · sin (θ−2 / 3π) + Io / 3) = 2 · I · sin (θ−2 / 3π) ( 8)
Iw = Iw1 + Iw2 = (I · sin (θ + 2 / 3π) −Io / 3) + (I · sin (θ + 2 / 3π) + Io / 3) = 2 · I · sin (θ + 2 / 3π) (9)
From the equations (7) to (9), the addition currents Iu, Iv, Iw of each phase cancel the zero-phase current Io, and are twice the amplitude of each phase current Iu1, Iv1, Iw1, Iu2, Iv2, Iw2, respectively. It can be seen that the current has an amplitude. Therefore, the phase currents Iu1, Iv1, Iw1, Iu2, Iv2, Iw2 of the three-phase coils 124, 126 are detected by the current sensors 161, 162 and the detection result of the current sensor 167 attached between the neutral points. Can be calculated by the following equation. In the embodiment, only the u phase is shown, but the same applies to the v phase and the w phase.
Iu1 = Iu / 2−Io / 3 (10)
Iu2 = Iu / 2 + Io / 3 (11)
[0041]
When the phase currents Iu1, Iu2, Iv1, Iv2, Iw1, Iw2 of the three-phase coils 124, 126 are calculated, the 2Y motor 22 can be driven by normal motor control using the calculation results.
[0042]
  Explained aboveFruitAccording to the power output device 120 of the embodiment, the current sensors 161 and 162 are attached to the u phase and the w phase of the corresponding two three-phase coils 124 and 126, respectively, and the detection results by the current sensors 161 and 162 are Based on the detection result of the current between the neutral points by the current sensor 167, the respective phase currents Iu1, Iv1, Iw1, Iu2, Iv2, Iw2 of the three-phase coils 124, 126 are calculated, and the 2Y motor 122 is calculated using the calculation results. Therefore, it is not necessary to attach a current sensor to each phase of the three-phase coil 124 and each phase of the three-phase coil 126. As a result, cost reduction of the power output device 120 can be realized.
[0043]
FruitIn the power output apparatus 120 of the embodiment, the installation of the common current sensors 161 and 162 in the case of controlling the drive of the 2Y motor 122 having the three-phase coil 124 and the three-phase coil 126 has been considered. Of these, a common current sensor may be installed when driving and controlling a first motor having one first three-phase coil and a second motor having the other second three-phase coil. However,, RealThe same effect as that of the power output device 120 of the embodiment can be obtained when the first and second motors are controlled with the same output, that is, the phase potentials Vu1, Vv1, Vw1 of the first three-phase coil. This is limited to the case where the amplitude and frequency of the (modulated wave) and the amplitude and frequency of each phase potential Vu2, Vv2, Vw2 (modulated wave) of the second three-phase coil are the same.
[0044]
  Basic form andIn the power output devices 20 and 120 of the embodiment, the capacitors 38 and 138 are connected to the positive buses 34 and 134 and the negative buses 36 and 136, but a DC power source is connected instead of the capacitors 38 and 138. Also good.
[0045]
  Basic form andIn the power output devices 20 and 120 of the embodiment, the DC power sources 40 and 140 are connected between the neutral points of the two three-phase coils 24, 26, 124, and 126. A DC power supply may be connected between the neutral points of the coils.
[0046]
Still another embodiment will be described with reference to FIGS. In the example of FIG. 7 described above, the third harmonic is superimposed. In the example of FIG. 10, instead of this, the potential of the neutral point of the three-phase coil 24 connected to the positive side of the DC power supply 40 is set to the maximum voltage of each phase modulation wave (maximum value of the instantaneous phase potential). Is corrected so as to coincide with the positive side of the voltage Vc of the capacitor 38. Thereby, the voltage Vc utilization factor of the capacitor 38 can be maximized.
[0047]
That is,
Vu1 = (2 / √3) Vc · sinθ + V0 (1)
Vu2 = (2 / √3) Vc · sinθ−V0 (2)
V3 = 1-MAX (Vu1, Vv1, Vw1)
(However, the apex of the triangular wave = 1 and the lower point of the triangular wave = −1) (3)
Vu1 * = (2√3) Vc · sinθ + V3 + V0 (5)
Vu2 * = (2√3) Vc · sinθ + V3−V0 (6)
And
[0048]
Thus, the voltage value obtained by subtracting the maximum voltage value of the three-phase modulation wave from the apex of the triangular wave (positive voltage of the capacitor 38) is defined as V3 (correction wave), and this is converted into each phase modulation wave (each phase current). Superimpose. As a result, the excess is subtracted for the portion where the phase current exceeds the potential Vc of the capacitor 38, and the maximum value of each phase modulation wave (phase potential) matches the voltage Vc of the capacitor 38. Therefore, the maximum output torque can be improved by maximizing the utilization factor of the voltage Vc of the capacitor 38 and reducing the amplitudes of the modulation signals Vu1 * and Vu2 *.
[0049]
Further, as shown in FIG. 11, the neutral point potential of the three-phase coil 26 connected to the negative side of the DC power source 40 is a capacitor whose minimum voltage value (minimum value of instantaneous phase potential) of each phase modulation wave is a capacitor. Correction can be made so as to coincide with the negative side of the voltage Vc of 38.
[0050]
That is,
Vu1 = (2 / √3) Vc · sinθ + V0 (1)
Vu2 = (2 / √3) Vc · sinθ−V0 (2)
V3 = -1-MIN (Vu1, Vv1, Vw1)
(However, the apex of the triangular wave = 1 and the lower point of the triangular wave = −1) (3)
Vu1 * = (2√3) Vc · sinθ + V3 + V0 (5)
Vu2 * = (2√3) Vc · sinθ + V3−V0 (6)
And
[0051]
Thus, as in the case of FIG. 10, by superimposing the correction wave V3, the excess is subtracted for the portion where the phase current exceeds the potential Vc of the capacitor 38 on the negative side, and the minimum of the phase potential is reduced. The value matches the negative side of the voltage Vc of the capacitor 38. Therefore, the maximum output torque can be improved by maximizing the utilization factor of the voltage Vc of the capacitor 38 and reducing the amplitudes of the modulation signals Vu1 * and Vu2 *.
[0052]
The embodiments of the present invention have been described above by using the embodiments. However, the present invention is not limited to these embodiments, and various embodiments can be implemented without departing from the gist of the present invention. Of course you get.
[Brief description of the drawings]
FIG. 1 of the present inventionBasic formIt is a block diagram which shows the outline of a structure of the power output device 20 which is.
FIG. 2 is an explanatory diagram for explaining a relationship between a three-phase coil 24 and a three-phase coil 26 of a 2Y motor 22;
3 shows the current flow in a state where the potential difference V012 between the neutral point of the three-phase coil 24 and the neutral point of the three-phase coil 26 is smaller than the voltage Vb of the DC power supply 40; FIG. 26 is an explanatory diagram focusing on the leakage inductance of FIG.
FIG. 4 shows the flow of current when the potential difference V012 between the neutral point of the three-phase coil 24 and the neutral point of the three-phase coil 26 is larger than the voltage Vb of the DC power supply 40; FIG. 26 is an explanatory diagram focusing on the leakage inductance of FIG.
5 shows three-phase coils 24 and 26 when the difference between the neutral point potential V01 of the three-phase coil 24 and the neutral point potential V02 of the three-phase coil 26 becomes the voltage Vb of the DC power supply 40. FIG. It is explanatory drawing which shows an example of the waveform of each phase electric potential Vu1, Vv1, Vw1, Vu2, Vv2, Vw2.
[Fig. 6]Basic formIt is a block diagram which shows the drive control performed by the electronic control unit 50 of the motive power output device 20 as a control block.
FIG. 7 is an explanatory diagram for explaining how modulation signals corresponding to the three-phase coils 24 and 26 of the 2Y motor 22 are obtained by superimposing third-order harmonics, respectively.
[Fig. 8]FruitIt is a block diagram which shows the outline of a structure of the power output device 120 of embodiment.
9 is a diagram illustrating an example of a u-phase addition current Iu (= Iu1 + Iu2) detected by a current sensor 161. FIG.
FIG. 10 is an explanatory diagram for explaining a state in which modulation signals corresponding to the three-phase coils 24 and 26 of the 2Y motor 22 are obtained by superimposing correction waves on the difference between the maximum value of the modulation wave of each phase and the capacitor voltage. is there.
FIG. 11 is an explanatory diagram for explaining how to obtain modulation signals respectively corresponding to the three-phase coils 24 and 26 of the 2Y motor 22 by superimposing correction waves on the difference between the maximum value of the modulation wave of each phase and the capacitor voltage. is there.
[Explanation of symbols]
  20, 120 Power output device, 22, 122 2Y motor, 24, 26 Three-phase coil, 30, 32, 130, 132 Inverter circuit, 34, 134 Positive bus, 36, 136 Negative bus, 38, 138 Capacitor, 40, 140 DC power supply, 50, 150 Electronic control unit, 52, 152 CPU, 54, 154 ROM, 56, 156 RAM, 61-67, 161, 162 Current sensor, 68, 168 Rotation angle sensor, 70, 72, 170, 172 Voltage Sensor, T11 to T16, T21 to T26 Transistor, D11 to D16, D21 to D26 Diode.

Claims (3)

And two star connection coils with the same phase with each other, the positive bus and the negative bus and two inverter circuits capable of supplying polyphase alternating current power to each of the previous SL two star connection coils sharing the said A first power source connected to the positive electrode bus and the negative electrode bus; a second power source connected between neutral points of the two star connection coils;
A power output device comprising control means for switching control of the switching elements of the two inverter circuits so that the same power is output by applying in-phase current to two corresponding star-shaped connecting coils,
Addition current detection for detecting the addition current of each current flowing through the two coils, which is attached to each phase of one star connection coil and the other two phases of the star connection coil. Means,
Neutral point current detection means for detecting a current flowing between the neutral points;
The two star connection coils used for the control of the control means and based on the addition current detected by the addition current detection means and the neutral point current detected by the neutral point current detection means Phase current calculation means for calculating a phase current flowing through each phase of
A power output device comprising: The power output device according to claim 1 ,
The phase current calculation means uses a value obtained by halving the addition current detected by the addition current detection means and a neutral point current detected by the neutral point current detection means as the star connection coil. A power output device, which is means for calculating each phase current based on a value divided by the number of phases. The power output device according to claim 1 or 2 ,
The two star connection coils are provided corresponding to one rotor, and constitute a single electric motor.

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