JP4903191B2 - Power converter for vehicle - Google Patents

Description

  The present invention relates to a vehicular power conversion device, and more particularly to a vehicular power conversion device in a vehicle-mounted rotating electrical machine capable of realizing highly efficient power generation with high reliability and a simple configuration.

  In conventional vehicle power generation devices, a full-wave rectification method using a diode is generally performed. However, with the aim of higher efficiency, a rectification method that uses a switching element to reduce loss due to the rectification element. Has come to be done.

  As this type of conventional example, an inverter circuit device for a three-phase rotating electrical machine for a vehicle that determines and controls the off-timing of the switching element of the own phase based on the phase voltage of the other phase has been proposed (for example, see Patent Document 1). .)

Japanese Patent No. 40233353

  In Patent Document 1, the off-timing of the self-phase switching element is determined and controlled by the phase voltage of the other phase. However, when the off-timing is determined based on the phase voltage of the other phase, switching is performed only at a maximum electrical angle of 120 degrees. There is a problem that there is a concern that efficiency may decrease and heat generation in the rectifier circuit portion may increase when power generation is performed at an electrical angle of about 160 degrees in a high load state where the on state cannot be performed. there were.

  The present invention has been made to solve such a problem, stores the timing obtained from the phase voltage of the own phase, and generates a signal for controlling the gate of the switching element based on the stored past data. Thus, an object of the present invention is to obtain a vehicular power conversion device that can realize gate control according to a load.

The present invention relates to a power conversion unit that is connected to a multiphase rotating electrical machine for a vehicle and includes a switching element and a diode connected in parallel to the switching element, and a gate control unit that performs on / off control of the switching element. The gate control unit is configured to perform rectification operation of the diode based on the phase voltage of each phase of the rotating electrical machine when the rotating electrical machine is in a power generation operation and the switching element is in an OFF state. A diode energization state detection unit that detects a diode energization state and outputs a timing signal indicating a diode on timing at which the diode is energized and a diode off timing at which the diode is deenergized, and the diode energization state detection unit from the diode energization state detection unit Based on the timing signal, the diode on timing A gate command generation unit that stores a time measurement value of energization time until timing, and generates a gate command to turn on the switching element during a diode energization state based on the stored time measurement value, and the gate command generation unit ON / OFF of the switching element based on the gate command output from the phase voltage of each phase of the rotating electrical machine and the timing signal indicating the diode ON timing output from the diode energization state detector have a gate command monitoring unit that performs validity determination of operation, the switching element is a one that is divided into a lower arm switching element on the upper arm side arm switching element and the lower arm, the Among the diodes, a diode connected in parallel to the upper arm switching element is an upper arm diode. When the diode connected in parallel to the lower arm switching element is a lower arm diode, the diode energization state detection unit is on the upper arm side at the power plus voltage Vp of the power conversion unit or more and the power supply The first upper arm threshold value V1 (H) is set within a range equal to or less than the value obtained by adding the diode forward voltage VF to the plus voltage Vp, and is larger than the value obtained by adding the diode forward voltage VF to the power supply plus voltage Vp. The second upper arm threshold value V2 (H) is set to be a value, the third upper arm threshold value V3 (H) is set to be a value smaller than the power supply plus voltage Vp, and the phase voltage is When the first upper arm threshold value V1 (H) and the second upper arm threshold value V2 (H) are held for a predetermined time or more, it is determined that the upper arm diode is energized, When the phase voltage is equal to or lower than the third upper arm threshold value V3 (H), it is determined that the upper arm diode is not energized, and on the lower arm side, the phase voltage is equal to or lower than the reference voltage Vn of the power conversion unit, and A first lower arm threshold value V1 (L) is set in a range equal to or larger than a value obtained by subtracting the diode forward voltage VF from the reference voltage Vn, and is set to be larger than a value obtained by subtracting the diode forward voltage VF from the reference voltage Vn. The second lower arm threshold value V2 (L) is set to be a small value, the third lower arm threshold value V3 (L) is set to be a value larger than the reference voltage Vn, and the phase voltage is When the first lower arm threshold V1 (L) and the second lower arm threshold V2 (L) are held for a predetermined time or more, it is determined that the lower arm diode is energized, and the phase voltage is Said third lower arm threshold V3 ( ) When the above is reached, it is determined that the lower arm diode is not energized, and the gate command monitoring unit turns on the gate command of the upper arm switching element while the upper arm diode of the power conversion unit is on. The phase voltage is greater than a value obtained by adding the voltage drop VDS1 obtained by multiplying the power source plus voltage Vp, the on-resistance of the switching element and the magnitude of the maximum current during power generation, and A gate command for turning on the upper arm switching element of the gate command generator when it is detected that the voltage falls below a fourth upper arm threshold V4 (H) set in a range smaller than the diode forward voltage VF. On the other hand, it is determined that the upper arm switching element is actually operating, and the lower arm diode of the power conversion unit is in the ON state. When the gate command for the lower arm switching element is turned on, the phase voltage is obtained by multiplying the reference voltage Vn by the ON resistance of the switching element and the maximum current during power generation. It is detected that the value is equal to or greater than a fourth lower arm threshold V4 (L) set to a range smaller than a value obtained by subtracting VDS1 and greater than a value obtained by subtracting the diode forward voltage VF from the reference voltage Vn. The lower arm switching signal of the gate command unit is determined to be actually operating with respect to the gate command to turn on the lower arm switching signal, the gate command monitoring unit of the power conversion unit While the upper arm diode is in the on state, after switching the gate command of the upper arm switching element from the on state to the off state, The time Count (H) from when the upper arm threshold value V4 (H) is equal to or higher than the fourth upper arm threshold value V3 (H) is measured, and the lower arm diode of the power conversion unit is turned on. In the middle, after the gate command of the lower arm switching element is switched from the on state to the off state, the fourth lower arm threshold value V4 (L) or less is reached and then the third lower arm threshold value V3 (L) or more. It is determined that each switching element is turned off before the diode is de-energized based on the measured time Count (H) and Count (L). A power conversion device for a vehicle characterized by detecting .

The present invention relates to a power conversion unit that is connected to a multiphase rotating electrical machine for a vehicle and includes a switching element and a diode connected in parallel to the switching element, and a gate control unit that performs on / off control of the switching element. The gate control unit is configured to perform rectification operation of the diode based on the phase voltage of each phase of the rotating electrical machine when the rotating electrical machine is in a power generation operation and the switching element is in an OFF state. A diode energization state detection unit that detects a diode energization state and outputs a timing signal indicating a diode on timing at which the diode is energized and a diode off timing at which the diode is deenergized, and the diode energization state detection unit from the diode energization state detection unit Based on the timing signal, the diode on timing A gate command generation unit that stores a time measurement value of energization time until timing, and generates a gate command to turn on the switching element during a diode energization state based on the stored time measurement value, and the gate command generation unit ON / OFF of the switching element based on the gate command output from the phase voltage of each phase of the rotating electrical machine and the timing signal indicating the diode ON timing output from the diode energization state detector have a gate command monitoring unit that performs validity determination of operation, the switching element is a one that is divided into a lower arm switching element on the upper arm side arm switching element and the lower arm, the Among the diodes, a diode connected in parallel to the upper arm switching element is an upper arm diode. When the diode connected in parallel to the lower arm switching element is a lower arm diode, the diode energization state detection unit is on the upper arm side at the power plus voltage Vp of the power conversion unit or more and the power supply The first upper arm threshold value V1 (H) is set within a range equal to or less than the value obtained by adding the diode forward voltage VF to the plus voltage Vp, and is larger than the value obtained by adding the diode forward voltage VF to the power supply plus voltage Vp. The second upper arm threshold value V2 (H) is set to be a value, the third upper arm threshold value V3 (H) is set to be a value smaller than the power supply plus voltage Vp, and the phase voltage is When the first upper arm threshold value V1 (H) and the second upper arm threshold value V2 (H) are held for a predetermined time or more, it is determined that the upper arm diode is energized, When the phase voltage is equal to or lower than the third upper arm threshold value V3 (H), it is determined that the upper arm diode is not energized, and on the lower arm side, the phase voltage is equal to or lower than the reference voltage Vn of the power conversion unit, and A first lower arm threshold value V1 (L) is set in a range equal to or larger than a value obtained by subtracting the diode forward voltage VF from the reference voltage Vn, and is set to be larger than a value obtained by subtracting the diode forward voltage VF from the reference voltage Vn. The second lower arm threshold value V2 (L) is set to be a small value, the third lower arm threshold value V3 (L) is set to be a value larger than the reference voltage Vn, and the phase voltage is When the first lower arm threshold V1 (L) and the second lower arm threshold V2 (L) are held for a predetermined time or more, it is determined that the lower arm diode is energized, and the phase voltage is Said third lower arm threshold V3 ( ) When the above is reached, it is determined that the lower arm diode is not energized, and the gate command monitoring unit turns on the gate command of the upper arm switching element while the upper arm diode of the power conversion unit is on. The phase voltage is greater than a value obtained by adding the voltage drop VDS1 obtained by multiplying the power source plus voltage Vp, the on-resistance of the switching element and the magnitude of the maximum current during power generation, and A gate command for turning on the upper arm switching element of the gate command generator when it is detected that the voltage falls below a fourth upper arm threshold V4 (H) set in a range smaller than the diode forward voltage VF. On the other hand, it is determined that the upper arm switching element is actually operating, and the lower arm diode of the power conversion unit is in the ON state. When the gate command for the lower arm switching element is turned on, the phase voltage is obtained by multiplying the reference voltage Vn by the ON resistance of the switching element and the maximum current during power generation. It is detected that the value is equal to or greater than a fourth lower arm threshold V4 (L) set to a range smaller than a value obtained by subtracting VDS1 and greater than a value obtained by subtracting the diode forward voltage VF from the reference voltage Vn. The lower arm switching signal of the gate command unit is determined to be actually operating with respect to the gate command to turn on the lower arm switching signal, the gate command monitoring unit of the power conversion unit While the upper arm diode is in the on state, after switching the gate command of the upper arm switching element from the on state to the off state, The time Count (H) from when the upper arm threshold value V4 (H) is equal to or higher than the fourth upper arm threshold value V3 (H) is measured, and the lower arm diode of the power conversion unit is turned on. In the middle, after the gate command of the lower arm switching element is switched from the on state to the off state, the fourth lower arm threshold value V4 (L) or less is reached and then the third lower arm threshold value V3 (L) or more. It is determined that each switching element is turned off before the diode is de-energized based on the measured time Count (H) and Count (L). since the vehicle power conversion device and detecting and storing the timing obtained from the phase voltage of its own phase, in the stored historical data, the gate control of the switching element That signal by generating, may enable realization of a gate control according to the load.

Embodiment 1 FIG.
An embodiment of the present invention will be described below.

  FIG. 1 is an exemplary view of a vehicle system to which a generator motor according to Embodiment 1 of the present invention is applied.

  In FIG. 1, an internal combustion engine 101 is connected to a generator motor 102 via a power transmission means 104 such as a belt, and electric energy obtained by AC-DC conversion by a generator motor 102 with respect to a storage battery 103 while the internal combustion engine 101 is in operation. To charge.

  FIG. 2 is an exemplary diagram illustrating an internal configuration of the generator motor 102 in FIG. 1.

  The generator motor 102 includes a power conversion device 110 indicated by a one-dot chain line and a motor generator unit 200 indicated by a two-dot chain line. In addition, a battery as a storage battery 103 is connected to the generator motor 102 via a P terminal for positive power input and an N terminal for ground input.

  As shown in FIG. 2, the motor generator unit 200 is provided with a vehicle multiphase rotating electrical machine. In FIG. 2, the motor generator unit 200 includes a three-phase generator motor armature winding 201 of U phase, V phase, and W phase, and a generator motor field winding 202, and a three-phase field winding method. It is illustrated as a generator motor. In the present invention, the rotating electrical machine performs not only the power generation operation but also the power running operation by the power conversion device 110.

  As shown in FIG. 2, the power conversion device 110 includes a power conversion unit 220 including a plurality of switching elements, and a gate control unit 210 that performs on / off control of the switching elements of the power conversion unit 220.

  The power conversion unit 220 includes a field switching element 221 for PWM control of the field current, a free wheel diode 222, upper arm switching elements 223a, b, and c that incorporate a parasitic diode, and a lower part that incorporates a parasitic diode. The arm switching elements 224a, b, c and the switching elements 223a, b, c and 224a, b, c are connected in parallel to each other. As described above, in the power conversion unit 220, the switching elements 223 and 224 and the diodes connected in parallel thereto are divided into the upper arm side and the lower arm side. In the power conversion unit 220, the upper arm switching elements 223 a, b, and c connect the U, V, and W phase terminals of the generator motor armature winding 201 and the P terminal of the positive power input from the storage battery (battery) 103. The U, V, and W phase terminals of the generator motor armature winding 201 are connected to the N terminal of the ground input from the storage battery (battery) 103 by the lower arm switching elements 224a, b, and c, respectively. ing.

  Here, in the exemplary diagram of FIG. 2, as described above, the motor generator unit 200 includes a three-phase field winding having a three-phase generator-motor armature winding 201 and a generator-motor field winding 202. Although the method generator motor is not limited to this case, the same applies to an arbitrary number of phases (for example, six phases) and an arbitrary field method (for example, permanent magnets). Further, not only the generator motor 102 in which the power conversion device 110 and the motor generator unit 200 are integrated as shown in FIG. 2, but also the power conversion device 110 and the motor generator unit 200 are physically divided. You may use the generator motor apparatus of the separate structure type comprised by the separate body as the generator motor 102. FIG.

  FIG. 3 is an exemplary diagram of functional blocks related to the power generation operation of the gate control unit 210. The gate control unit 210 performs on / off command control of the upper arm switching elements 223a, b, c and the lower arm switching elements 224a, b, c provided in the power conversion unit 220 with the configuration shown in FIG.

  As shown in FIG. 3, the gate control unit 210 includes a diode energization state detection unit 122, a gate command generation unit 132, and a gate command monitoring unit 133.

  The diode energization state detection unit 122 detects the diode energization state due to the rectification operation of the diode based on the phase voltage of each phase of the rotating electrical machine when the rotating electrical machine is in the power generation operation and the switching element is in the off state. Then, a timing signal indicating a diode-on timing at which the diode is energized and a diode-off timing at which the diode is de-energized is output.

  The gate command generation unit 132 stores the time measurement value of the energization time from the diode on timing to the diode off timing based on the timing signal from the diode energization state detection unit 122, and based on the stored time measurement value, the diode A gate command for turning on the switching element during the energized state is generated.

  The gate command monitoring unit 133 is based on the gate command output from the gate command generation unit 132, the phase voltage of each phase of the rotating electrical machine, and the timing signal indicating the diode ON timing output from the diode energization state detection unit 122. Thus, the validity of the on / off operation of the switching element is determined.

  Each of these components will be described in detail below.

  The diode energization state detection unit 122 is a means for detecting the conduction states of the diodes connected in parallel to the switching elements 223 and 224 based on the input of the three-phase terminal voltages Vu, Vv, and Vw. is there.

  When the diode is on (forward current flows), the diode forward voltage VF is generated across the diode, while when the diode is off (forward current is not flowing). The both ends of the diode are open.

  Therefore, the ON timing of the diodes connected in parallel to the upper arm switching elements 223a, b, and c (hereinafter referred to as upper arm diodes) is the N terminal potential Vn (hereinafter referred to as the reference terminal voltage Vn) of the power converter 110. If the P terminal voltage is Vp, the three-phase terminal voltages are Vu, Vv, Vw, and the diode forward voltage VF, the following determination formula can be used.

U phase upper arm diode ON state detection judgment formula: Vp ≦ Vu ≦ Vp + VF
V-phase upper arm diode ON state detection judgment formula: Vp ≦ Vv ≦ Vp + VF
W-phase upper arm diode ON state detection judgment formula: Vp ≦ Vw ≦ Vp + VF

  Similarly, the off timing of the upper arm diode connected in parallel to the upper arm switching elements 223a, b, c can be determined by the following determination formula.

U phase upper arm diode off state detection judgment formula: Vu <Vp
V-phase upper arm diode off state detection judgment formula: Vv <Vp
W-phase upper arm diode off state detection judgment formula: Vw <Vp

  Similarly, the on-timing of a diode (hereinafter referred to as a lower arm diode) connected in parallel to the lower arm switching elements 224a, b, and c can be determined by the following determination formula.

U-phase lower arm diode ON state detection judgment formula: −VF ≦ Vu ≦ 0
V-phase lower arm diode ON state detection judgment formula: −VF ≦ Vv ≦ 0
W-phase lower arm diode ON state detection judgment formula: −VF ≦ Vw ≦ 0

  Similarly, the off timing of the lower arm diode connected in parallel to the lower arm switching elements 224a, b, c can be determined by the following determination formula.

U-phase lower arm diode off state detection judgment formula: 0 <Vu
V-phase lower arm diode off state detection judgment formula: 0 <Vv
W-phase lower arm diode off state detection judgment formula: 0 <Vw

  In particular, in the diode energization state detection unit 122, as shown in the exemplary diagram of FIG. 4, on the upper arm side, the first upper side in the range of Vp or more and less than or equal to the voltage obtained by adding VF to Vp (Vp + VF). Arm upper threshold V1 (H) (for example, V1 (H) = Vp) and second upper arm threshold V2 (H) having a value larger than the voltage obtained by adding VF to Vp (Vp + VF) (for example, in the entire operation range) If the maximum value of VF is 0.6V, V2 (H) = Vp + 0.7V) and a third upper arm threshold V3 (H) having a value smaller than Vp are set, and the phase voltage is If the upper arm threshold value V1 (H) and the second upper arm threshold value V2 (H) are held for a certain time Tdelay1 or more, the Hon signal is set to significant “H” (the upper arm diode is energized). On the other hand, the phase voltage is higher than the third Over arm threshold V3 when becomes (H) hereinafter referred to as insignificant "L" to Hon signal (the upper arm diode is determined that a non-energized state).

  On the lower arm side, the first lower arm threshold V1 (L) in a range equal to or lower than Vn and equal to or higher than the voltage obtained by subtracting VF from Vn (Vn−VF) and the voltage obtained by subtracting VF from Vn ( A second lower arm threshold V2 (L) smaller than Vn−VF) and a third lower arm threshold V3 (L) larger than Vn are set, and the phase voltage becomes the first lower arm threshold V1 ( L) and the second lower arm threshold value V2 (L) are held for a certain time Tdelay1 or more, the Lon signal is set to significant “H” (the lower arm diode is determined to be energized), When the phase voltage becomes equal to or higher than the third lower arm threshold value V3 (L), the Lon signal is arbitrarily set to “L” (the lower arm diode is determined to be in a non-energized state). Here, Vp> V3 (H)> V3 (L)> Vn.

  In this embodiment, as described above, as a method for detecting the diode energization state, the value of the phase voltage is maintained for a certain period of time between the first threshold value and the second threshold value on the upper arm side and the lower arm side. In this case, it is determined that the diode is in the on state, so it can be confirmed that the diode is in the on state. For example, the diode has an open failure, and the diode is in the on state accurately. Even when it is not possible to detect the vehicle power converter, it is possible to realize a vehicle power converter that does not turn on the gate command of the switching element.

  Furthermore, since the diode forward voltage VF varies depending on the forward current flowing through the diode and the temperature, the first threshold value is set to be equal to or lower than the minimum voltage of the diode VF used in the device, and the second threshold value is set to By setting the voltage to be equal to or higher than the maximum voltage of the VF of the diode used in the apparatus, it becomes possible to accurately detect the ON state of the diode.

  In this embodiment, it is possible to reliably detect whether or not the diode is in the rectifying region even if VF or the like changes due to the influence of temperature or the like in this way.

  Next, the gate command generator 132 shown in FIG. 3 will be described. As shown in FIG. 3, the gate command generation unit 132 is provided with a measurement unit 132a, a comparator 132b, a storage unit 132c, and an off timing determination unit 132d.

The gate command generate unit 132, is input from the diode conducting state detector 122, a diode conduction timing signal X _on showing the diode-on timing, resets start a counter operation of the measuring part 132a, thereby, the measurement unit 132a is Then, the counter operation for measuring the energization time of the diode is started. Is input from the diode conducting state detector 122 during the counter operation, by detecting a time became diode OFF state at the diode conduction timing signal X _on showing the diode off timing, to terminate the counter operation, the diode-on timing The measured value of the energization time from to the diode off timing is obtained and stored in the storage unit 132c. The off timing determination unit 132d generates a timing signal IN2 for turning off the gate based on the measured value of the past energization time stored in the storage unit 132c, and inputs the timing signal IN2 to the comparator 132d. The comparator 132d compares the output IN1 from the measurement unit 132a described above with the output IN2 from the off timing determination unit 132d.

As a result of the comparison, when the following conditional expression is satisfied, that is, when IN2 is equal to or greater than IN1, the comparator 132b sends a gate signal X _Gate that sets the gate output X _on to a significant state to the power converter 220. And switching elements 223 and 224 of power converter 220 are turned on.

    IN1 ≦ IN2

  Here, in the gate command generation unit 132, the number of past timing data (self-phase energization time) stored in the storage unit 132c may be one. The timing signal IN2 for turning off the gate is generated by the off-timing determination unit 132d based on the minimum value of the past timing data (for example, 8 pieces of data are stored in the case of an 8-pole stator) By doing so, it becomes possible to prevent erroneous control due to the influence of power generation variation for each pole due to the structure of the rotating electrical machine.

  Although idling / stopping is effective as a vehicle fuel efficiency improvement method, it can be used as power for restarting engine cranking by operating the rotating electrical machine not only with the power generation operation but also with the power converter. However, it is important to detect whether or not a power running operation is possible, for example, to detect an abnormality that causes a problem in the switching operation even if the power generation operation is possible.

Next, the gate command monitoring unit 133 shown in FIG. 3 will be described.
The gate signal X _Gate output from the gate command generation unit 132 is input to the power conversion unit 220 to control the upper and lower arm switching elements 223 and 224 and is also input to the gate command monitoring unit 133. In the gate command monitoring unit 133, based on the gate signal X _Gate , the diode energization timing signal X _on input from the diode energization state detection unit 122, the phase voltages Vu, Vv, Vw of each phase, etc. 223 and 224 operations and timing monitoring are performed.

  FIG. 5 is an example of a circuit for diagnosing whether the switching element is functioning normally with respect to the gate command in the first embodiment. FIG. 6 is a timing chart showing a diagnosis operation of whether or not the switching element is functioning normally with respect to the gate command in the first embodiment.

The circuit shown in FIG. 5 includes a pair of comparators for comparing the phase voltage and fourth threshold values V4 (H) and V4 (L), which will be described later, and outputs from the comparators and H _Gate and L _Gate. And a pair of AND circuits for obtaining the logical products (1) and (2), respectively, and an OR circuit for obtaining the logical sum of the outputs (1) and (2) from the AND circuits. . Note that one of the comparators compares the phase voltage with V4 (H) and outputs a significant “H” when the phase voltage> V4 (H) is established, and the other comparator compares the phase voltage with V4 (L). ) And when the phase voltage <V4 (L) is established, a significant “H” is output.

  In the gate command monitoring unit 133, in particular, as illustrated in FIGS. 5 and 6, when the gate signal of each phase is in a significant state, the switching element of each phase is normally turned on. Diagnose when the gate command becomes significant.

  That is, when the gate command of the upper arm switching elements 223a, b, and c is turned on while the upper arm diode of the power conversion unit 220 is on, the phase voltage becomes the following fourth upper arm threshold V4 (H). By detecting the following, it can be diagnosed that the switching element is normally turned on.

  The fourth upper arm threshold value V4 (H) is larger than the value (Vp + VDS1) obtained by adding Vp to the voltage drop VDS1 obtained by multiplying the on-resistance of the switching element and the maximum current during power generation. A range smaller than the value obtained by adding VF (Vp + VF) is set. However, V3 (H) <Vp <V4 (H) <Vp + VF.

  On the lower arm side, when the gate command of the lower arm switching element is turned on while the lower arm diode is on, the phase voltage becomes equal to or higher than the fourth lower arm threshold V4 (L) described below. By detecting this, it can be diagnosed that the switching element is normally turned on.

  The fourth lower arm threshold value V4 (L) is smaller than a value (Vn−VDS1) obtained by subtracting a voltage drop VDS1 obtained by multiplying the on-resistance of the switching element by the maximum current during power generation from Vn (Vn−VDS1). A range larger than the value obtained by subtracting VF (Vn−VF) is set. However, Vn−VF <V4 (L) <Vn <V3 (L) <V3 (H).

  Conversely, if the phase voltage does not change as described above even if the gate command becomes significant, it is considered that the switching element cannot be turned on, and even if the power generation operation can be continued with a parasitic diode, etc. Since the operation cannot be performed, this is detected as an abnormality, and the abnormal state is notified to the outside, whereby the abnormal state can be recognized on the vehicle side and the idling / stop operation can be prohibited.

However, even if the gate command becomes significant, there is a time delay until the switching element is actually turned on. Therefore, an abnormal state is detected in a transient state, and an abnormal state is detected to prevent erroneous detection. The circuit requires a delay element T _delay2 in consideration of the switching delay as shown in FIG.

  Thus, in this embodiment, when the gate signal of the switching element in the phase in which the diode is on is turned on, the voltage drop at the switching element is reduced from the forward current of the diode to the fourth threshold value. By detecting that the voltage drop is caused by the ON resistance of the smaller switching element, it is possible to detect that the switching element is normally switching.

In the method using the past self-phase timing information according to the present invention, the gate command X _Gate is involuntarily controlled earlier than when the diode is actually energized in consideration of the control margin for sudden engine rotation. The fourth upper arm threshold value V4 (H) is not limited to this case, and the gate command of the upper arm switching element 223 is switched from the on state to the off state while the upper arm diode of the power conversion unit 220 is on. The time Count (H) from the above to the third upper arm threshold value V3 (H) or less is measured. Similarly, when the lower arm diode is in the ON state, the gate command of the lower arm switching element 224 is measured. After switching from the ON state to the OFF state, the time from when the lower arm threshold value V4 (L) is lower than or equal to the fourth lower arm threshold value V3 (L) or higher Count (L) may be measured to detect that each switching element is off before the diode is de-energized.

  FIG. 7 shows an example of a circuit that operates in this way and diagnoses the validity of the gate-off command timing. FIG. 8 shows the timing of the operation for diagnosing the validity of the gate-off command timing by the circuit. A chart is shown.

7 and FIG. 8, the gate signals of the respective phases become ineffective, the rectification by the diode is turned off after the phase voltage exceeds the fourth threshold value V4, and the diode energization timing signal X _on is By measuring the time count until the idle state is reached, the timing at which the gate of the switching element is turned off by the off command H _Gate can be monitored, and it becomes possible to perform highly reliable gate command control.

  As described above, in the example of FIGS. 7 and 8, the induced voltage decreases from the state where the switching element is operated as an active diode to the normal diode rectification by turning off the gate signal. By measuring the time until the rectification operation by OFF is turned off, it is possible to evaluate the validity of the gate-off command timing.

  Further, an open mode failure is also assumed as a failure mode of the switching element. When an open failure occurs, the induced voltage of each phase is not clipped by Vp on the upper arm side due to the diode and Vn on the lower arm side, so that each phase voltage is the second upper arm threshold V2 (H ) And the lower arm side is detected to be smaller than the second lower arm threshold V2 (L), so that it is possible to detect that the switching element has an open failure. When an open failure occurs, normal switching operation cannot be performed during power running and the engine cannot be restarted. Therefore, avoid idling / stopping on the vehicle side.

  In addition, when the rotational speed is low, or when the field current is small and the generated current is small, the timing change when turning off the switching element is large, and the gate command for the switching element is issued only in the region where the diode is originally on. There is a high possibility of erroneous control of the place to be turned on, and if the gate command is erroneously controlled, the torque will increase and the sound will increase, affecting the drivability of the vehicle.

  In addition, when the amount of power generation is small, the gate command for the switching element is not turned on, and even a rectifying operation using a diode does not cause a large loss as a power converter. It doesn't matter.

  As described above, in the first embodiment, the switching element has an open failure by detecting that the phase voltage exceeds the second threshold value V2 regardless of whether it is in a power running operation or a power generation operation. Can be detected.

  However, the operation of synchronous rectification becomes unstable unless the amount of power generation is large, and torque fluctuations, abnormal noise, and the like may occur.

  In addition, when the amount of power generation is small, the heat loss during power generation is small and synchronous rectification is not necessarily performed.

The gate command monitoring unit 133 determines whether to lock the gate command when the diode is on during power generation based on the electrical angle period of the rotor and the energization time ratio when the diode is on. It is determined whether or not an ON command is output as a gate command for the switching element when is in an ON state. That is, the on time of the diode conduction timing signal X _on, the ratio of the repetition time of the diode conduction timing signal X _on, determines whether or not to lock the gate instruction.

For example, when the diode energization timing signal _Xon is the same when the power generation amount is large and the case where the power generation amount is large (that is, the field current is large), diode rectification is considered. If the voltage is not clamped by the voltage, the induced voltage is high. On the other hand, if the amount of power generation is small (that is, the field current is small), the induced voltage is small if the voltage is not clamped by diode rectification. .

When generating power for a vehicle, the induced voltage waveform is actually clamped by a diode, but the clamped voltage is the same regardless of the induced voltage, so the length of the X _on signal inevitably is the induced voltage. When the high field current is large, that is, when the generated current is large, the time becomes long.

However, this example is the case of power generation at the same rotation, and as the vehicular power generation device, the engine rotation changes depending on the running state, so the ratio of the time corresponding to one cycle of the electrical angle and the time of the X _on signal ( Thereafter, it is necessary to judge called "diode current ratio"), as an example of a method of obtaining one period worth of time of the electrical angle, from the rising edge of the repetition time (X _on signal X _on signal of the next X _on It is conceivable to use the time between rising edges of a signal = Timexon.

Whether the threshold level to allow synchronous rectification (condition), the motor characteristics, but not be generalized by the matching of the vehicle, for example to allow synchronous rectification in _{X on /Timexon≧0.4, X on / Timexon} < When 0.35, synchronous rectification is disabled.

  Further, in the power generation operation by the field winding type rotary electric machine, the field current is covered by the current obtained by the electric power generation of the rotary electric machine, so the rotation speed is low and the consumption of the field current is large with respect to the power generation amount. The threshold to be allowed is changed depending on the ratio and the case where the rotational speed is high and the consumption of the field current is small relative to the amount of power generation (that is, synchronous rectification is allowed depending on the rotational speed). It is also conceivable to change the threshold to be used, or to change the threshold for allowing synchronous rectification according to the magnitude of the field current.

  As described above, in this embodiment, based on the electrical angle period of the rotor and the energization time ratio of the diode being on, an on command is output as a gate command for the switching element when the diode is on. As the amount of power generation increases, the time ratio between the diode-on time and each period of the rotor electrical cycle increases, and whether to perform synchronous rectification Is possible.

  Furthermore, normal diode energization timing may be detected as illustrated in the example of FIG.

  The diode energization state detection signal between the phases when the power generation operation is normally performed as shown in FIG. 9 is “UHon rising detection → VHon rising detection → WHon rising detection → UHon rising detection →... , Repeat) ”,“ UHon fall detection → VHon fall detection → WHon fall detection → UHon fall detection →... (Hereinafter repeated) ”,“ ULon rise detection → VLon rise detection → WLon rise detection → ULon “Rising detection →... (Hereinafter repeated)”, “ULon falling detection → VLon falling detection → WLon falling detection → ULon falling detection →... (Hereinafter repeated)”.

  In addition, when a ground fault occurs in the coil, sufficient induced power is not generated. Therefore, it is possible to detect this and detect an abnormal state of the coil. Accordingly, the gate command monitoring unit 133 determines that the diode of the other phase is changed from the OFF state until the diode of the own phase is changed from the OFF state to the ON state. If it is determined that the ON state always occurs once in each phase, it can be determined whether the coil state is normal or abnormal.

  Therefore, the gate command monitoring unit 133 monitors that the diode energization timing of each phase becomes the above-described operation relationship at the normal time. For example, as shown in FIG. When the phase) has a ground fault, the phase voltage is normal in the U phase and the V phase, and only the W phase is constant as shown in FIG. The signal becomes as shown in FIG. 11, and the abnormal state can be detected when the on / off timing between the phases is not normal. When an abnormality is detected, the switching operation of the phase corresponding to the abnormality during power generation is prohibited and the power running operation is prohibited.

  The operation of the ground fault is described as an example. However, other faults (such as a low fault power fault and a switching element short-circuit fault) can be similarly monitored.

  However, since the above method does not use a timer or numerical operation for monitoring, it can be realized with a simple logic circuit, but a short circuit failure in an armature coil in which the apparent number of windings changes, It may not be possible to detect a power generation failure due to disconnection or the like.

  Also, if there is a resistance component and there is a power fault, ground fault, or if the coil is disconnected, etc., there will be variations in the diode on time of each phase. It is possible to detect. Therefore, the gate command monitoring unit 133 detects an error by monitoring variations in the diode energization ratio of each phase.

  For example, when normal, as shown in FIG. 9, there is no significant difference in the diode current ratio of each phase, but for example, when the W-phase coil is short-circuited between the windings and the electromotive force is small As shown in FIG. 11, the diode ON time of the WH phase and the WL phase is shortened compared to the U and V phases, so that the device abnormality is monitored by the variation in the diode conduction ratio between the phases. It becomes possible.

  As described above, the present embodiment includes means for detecting the diode energization state when the rectification operation is performed only with the diode (the switching element is not turned on), and the diode enters the energization state. After that, the time until the diode becomes non-energized is sequentially stored, the switching element is turned on when the diode is energized, and then the turn-off time of the switching element is subtracted from the stored diode energizing time. The switching element is turned off at the timing obtained by subtracting the time.

  Therefore, according to the present embodiment, depending on the past time interval (energization width) between the diode on timing when the diode is energized and the diode off timing when the diode is deenergized, Since the ON / OFF command for the arm switching element is generated, it is possible to easily obtain the ON / OFF command for the upper and lower arm switching elements that are not affected by load fluctuations in almost all areas where the diode is ON. Therefore, it is possible to realize a vehicular power conversion device that enables highly efficient and highly reliable power generation operation.

  In addition, since switching elements can be controlled on / off for each phase, even if one phase fails, a healthy phase can be controlled by continuously controlling switching elements on / off. It is possible to generate less power.

Embodiment 2. FIG.
Each threshold value (threshold level) in the present invention described in the first embodiment needs to have an accuracy of about 0.1 V including a diode forward voltage VF (generally 0.5 V to 0.8 V). However, in a normal battery system, the voltage at the power supply terminal is the battery voltage, so there is no significant fluctuation.Therefore, even if the threshold is set with resistance voltage division based on the battery voltage, there is not much error. Does not occur. However, for example, when the power source is not a battery but a capacitor and the voltage change is large, a threshold circuit as shown in FIG. 12 is required so that the threshold error is reduced.

  The circuit of FIG. 12 is for comparing a pair of adders for adding the power supply plus voltage Vp to the reference voltages Ref1 and Ref2, respectively, and Ref1 ′ and Ref2 ′ output from the adder and the phase voltage. It consists of a pair of comparators 1 and 2.

  However, if there are a plurality of threshold values, the circuit of FIG. 12 requires a plurality of voltage addition circuits that generate the threshold values of the respective comparators, which increases the circuit scale.

  In addition, when using a capacitor power supply represented by an electric double layer capacitor for the purpose of efficiently storing regenerative energy at the time of idling stop, in the method of directly detecting the energization state using each phase voltage, The change in the positive power supply terminal voltage is large, making it difficult to set the threshold value when considering the realization circuit.

  Therefore, a circuit is configured as shown in FIG. 13, and each phase voltage of the power conversion unit 220 is used as each phase voltage used for threshold determination on the upper arm side of the diode energization state detection unit 122 and the gate command monitoring unit 133. You may make it use what differentially amplified the potential difference with the power supply plus voltage Vp.

  By using a circuit as shown in FIG. 13 and differentially amplifying the potential difference between each phase voltage on the upper arm side and Vp in this way, the threshold can be easily set even when Vp changes. It becomes possible to.

  Further, not limited to the example of FIG. 13, the portions necessary as the phase voltages for detecting the upper arm diode ON state are voltages near the power supply voltage, and therefore only the difference voltage in the vicinity is amplified as shown in FIG. 14. By adopting such a differential amplifier configuration, an adder is not required for threshold setting, and the circuit can be simplified.

  In the configuration of FIG. 14, the phase voltage is positively input and the power supply positive voltage Vpga is negatively input, and a pair for comparing the outputs from the differential amplifier and the reference voltages Ref 1 and Ref 2 respectively. Comparators Comp1 and Comp2 are provided.

  Further, the circuit is configured as shown in FIG. 15, and Vn of the power conversion unit 220 and each phase are used as the phase voltages used for threshold determination on the lower arm side of the diode energization state detection unit 122 and the gate command monitoring unit 133. You may make it use what differentially amplified the potential difference with a voltage.

  In FIG. 15, the circuit for detecting the lower arm diode on state is configured by a differential amplifier similar to that in FIG. 13, but by configuring the circuit so that the output is inverted from that in FIG. The threshold can be shared, and the circuit can be simplified.

It is the block diagram which showed an example of the vehicle system in Embodiment 1 which concerns on this invention. It is the block diagram which showed an example of the internal structure of the generator motor of the vehicle system in Embodiment 1 which concerns on this invention. It is the block diagram which showed an example of the functional block in the gate control part provided in the generator motor in Embodiment 1 which concerns on this invention. It is a timing chart which showed operation | movement of the diode energization state detection part provided in the gate control part in Embodiment 1 which concerns on this invention. The circuit diagram which showed an example of the circuit which comprises the gate instruction | command monitoring part provided in the gate control part in Embodiment 1 which concerns on this invention, and diagnoses whether the switching element is functioning normally with respect to a gate instruction | command It is. It is the timing chart which showed the diagnostic operation | movement whether the switching element is functioning normally with respect to a gate command by the gate command monitoring part provided in the gate control part in Embodiment 1 which concerns on this invention. It is the circuit diagram which showed an example of the circuit which comprises the gate command monitoring part provided in the gate control part in Embodiment 1 which concerns on this invention, and diagnoses the validity of the gate-off command timing. It is a timing chart which showed the diagnostic operation | movement of the validity of the gate-off command timing by the gate command monitoring part provided in the gate control part in Embodiment 1 which concerns on this invention. It is a timing chart which showed the detection operation | movement of the normal diode energization timing by the gate command monitoring part provided in the gate control part in Embodiment 1 which concerns on this invention. It is a timing chart which showed the detection operation | movement of the diode energization timing at the time of one-phase ground fault by the gate command monitoring part provided in the gate control part in Embodiment 1 which concerns on this invention. It is a timing chart which showed the detection operation | movement of the diode energization timing at the time of the short circuit between 1 phase coils by the gate command monitoring part provided in the gate control part in Embodiment 1 which concerns on this invention. It is the circuit diagram which showed an example of the threshold potential generation circuit in Embodiment 2 which concerns on this invention. It is the circuit diagram which showed an example of the upper arm differential circuit in Embodiment 2 which concerns on this invention. It is the circuit diagram which showed an example of the comparator circuit using the differential circuit in Embodiment 2 which concerns on this invention. It is the circuit diagram which showed an example of the lower arm differential circuit in Embodiment 2 which concerns on this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 101 Internal combustion engine, 102 Generator motor, 103 Storage battery, 110 Power converter, 200 Motor generator part, 201 Generator motor armature winding, 202 Generator motor field winding, 210 Gate control part, 211 Rotor position detection part, 212 Diode conduction state detection unit, 213 timing processing unit, 214 gate command generation unit, 215 gate command monitoring unit, 220 power conversion unit, 221 field switching element, 222 freewheel diode, 223a U-phase upper arm switching element (UH), 223b V-phase upper arm switching element (VH), 223c W-phase upper arm switching element (WH), 224a U-phase lower arm switching element (UL), 224b V-phase lower arm switching element (VL), 224c W-phase lower arm switch N Element (WL).

Claims (8)

A power conversion unit connected to the vehicular multiphase rotating electrical machine and configured by a switching element and a diode connected in parallel to the switching element;
A gate control unit that performs on / off control of the switching element,
The gate controller is
When the rotating electrical machine is in a power generation operation and the switching element is in an OFF state, a diode energization state due to a rectifying operation of the diode is detected based on a phase voltage of each phase of the rotating electrical machine, and the diode A diode energization state detector that outputs a timing signal indicating a diode-on timing when the diode is energized and a diode-off timing when the diode is de-energized;
Based on the timing signal from the diode energization state detection unit, the time measurement value of the energization time from the diode on timing to the diode off timing is stored, and based on the stored time measurement value, the diode energization state during the diode energization state A gate command generator for generating a gate command to turn on the switching element;
Based on the gate command output from the gate command generation unit, the phase voltage of each phase of the rotating electrical machine, and the timing signal indicating the diode-on timing output from the diode energization state detection unit, the switching have a gate command monitoring unit that performs validity determination of the elements of the on / off operation,
The switching element is divided into an upper arm switching element on the upper arm side and a lower arm switching element on the lower arm side,
Among the diodes, a diode connected in parallel to the upper arm switching element is an upper arm diode, and a diode connected in parallel to the lower arm switching element is a lower arm diode,
The diode energization state detector is
On the upper arm side, the first upper arm threshold value V1 (H) is set in a range not less than the power source plus voltage Vp of the power converter and not more than the value obtained by adding the diode forward voltage VF to the power source plus voltage Vp. The second upper arm threshold value V2 (H) is set so as to be larger than the value obtained by adding the diode forward voltage VF to the power supply plus voltage Vp, and is set to a value smaller than the power supply plus voltage Vp. The third upper arm threshold V3 (H) is set so that the phase voltage is constant between the first upper arm threshold V1 (H) and the second upper arm threshold V2 (H). When it is held for more than the time, it is determined that the upper arm diode is energized, and when the phase voltage is equal to or lower than the third upper arm threshold V3 (H), it is determined that the upper arm diode is not energized,
On the lower arm side, a first lower arm threshold value V1 (L) is set within a range that is equal to or lower than the reference voltage Vn of the power converter and equal to or larger than a value obtained by subtracting the diode forward voltage VF from the reference voltage Vn. The second lower arm threshold value V2 (L) is set so as to be smaller than a value obtained by subtracting the diode forward voltage VF from the reference voltage Vn so as to be larger than the reference voltage Vn. A third lower arm threshold value V3 (L) is set, and the phase voltage is maintained for a certain time or more between the first lower arm threshold value V1 (L) and the second lower arm threshold value V2 (L). The lower arm diode is energized, and when the phase voltage is equal to or higher than the third lower arm threshold V3 (L), the lower arm diode is de-energized,
The gate command monitoring unit
When the gate command of the upper arm switching element is turned on while the upper arm diode of the power conversion unit is in the on state, the phase voltage is the power source plus voltage Vp, the on resistance of the switching element, Less than or equal to the fourth upper arm threshold V4 (H) set to a range larger than the sum of the voltage drop VDS1 obtained by multiplying the magnitude of the maximum current and smaller than the diode forward voltage VF. When it is detected that the upper arm switching element is actually operating with respect to the gate command to turn on the upper arm switching element of the gate command generation unit,
When the gate command of the lower arm switching element is turned on while the lower arm diode of the power conversion unit is on, the phase voltage is changed from the reference voltage Vn to the on resistance of the switching element and the maximum during power generation. A fourth value set in a range smaller than a value obtained by subtracting the voltage drop VDS1 obtained by multiplying by the magnitude of the current and larger than a value obtained by subtracting the diode forward voltage VF from the reference voltage Vn. When it is detected that the lower arm threshold value V4 (L) is exceeded, it is determined that the lower arm switching element is actually operating in response to the gate command for turning on the lower arm switching signal of the gate command unit. ,
The gate command monitoring unit
While the upper arm diode of the power conversion unit is in the on state, the gate command of the upper arm switching element is switched from the on state to the off state, and then the fourth upper arm threshold value V4 (H) or more is reached. Measure the time Count (H) until the third upper arm threshold V3 (H) or less,
While the lower arm diode of the power conversion unit is in the on state, the gate command of the lower arm switching element is switched from the on state to the off state, and then the fourth lower arm threshold value V4 (L) or less is reached. Measure the time Count (L) until the third lower arm threshold V3 (L) or more,
A vehicular power converter characterized in that , based on the measured time Count (H) and Count (L), it is detected that each switching element is turned off before the diode is de-energized . The number of time measurement values stored in the gate command generation unit is greater than the number of poles of the rotating electrical machine,
The gate command generation unit is configured to turn off the switching element before the timing at which the diode changes from the energized state to the non-energized state based on the minimum value of the stored time measurement values. The vehicle power converter according to claim 1, wherein the control signal is generated.   The gate command monitoring unit is configured such that the diode of the other phase changes from the off state to the on state while the diode of the own phase changes from the off state to the on state, and then the diode of the own phase changes from the off state to the on state again. The vehicle power conversion device according to claim 1, wherein it is determined that the occurrence of occurrence always occurs once in each phase.   The gate command monitoring unit detects a failure in a stator portion based on an imbalance between an electrical angle period of a rotor of each phase of the rotating electrical machine and an energization time when the diode is on. Item 4. The vehicle power converter according to Item 1. The diode energization state detection unit uses, as each phase voltage used for threshold determination on the upper arm side, a voltage obtained by differentially amplifying a potential difference between each phase voltage of the power conversion unit and the power supply plus voltage Vp. The vehicular power conversion device according to claim 1 . The gate command monitoring unit uses, as each phase voltage used for threshold determination on the upper arm side, a voltage obtained by differentially amplifying a potential difference between each phase voltage of the power conversion unit and the power supply plus voltage Vp. The power converter for vehicles according to claim 2 . The diode energization state detection unit uses, as each phase voltage used for lower arm side threshold determination, a voltage obtained by differentially amplifying a potential difference between the reference voltage Vn of the power conversion unit and each phase voltage. vehicle power converter according to claim 1, wherein. The gate command monitoring unit uses, as each phase voltage used for threshold determination on the lower arm side, a voltage obtained by differentially amplifying a potential difference between the reference voltage Vn of the power conversion unit and each phase voltage. The power converter for vehicles according to claim 2 .

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