JP2003079195A - Generator motor unit for vehicle employing field winding type synchronous machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a generator motor unit for vehicle in which the reliability of an entire unit is enhanced significantly as compared with a conventional unit by slightly complicating its arrangement. SOLUTION: Since only a switching element 22 for controlling a field current comprises a series connection of a plurality of switching elements 221 and 222 in a current control section 2, a generator motor unit for vehicle in which the reliability of the entire unit is enhanced significantly as compared with a conventional unit by slightly complicating its arrangement can be realized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicular generator-motor apparatus using a field winding type synchronous machine.

[0002]

2. Description of the Related Art In recent years,
Technology has been developed to perform various functions such as engine start, power generation, in-vehicle device drive at idle stop, regenerative braking, torque assist, etc. with a single vehicle generator-motor. It is common to adopt a synchronous machine that is simple and highly efficient.

As a synchronous machine for this vehicle generator-motor,
Although types such as a magnet field type, a field winding type, and a combination type of a magnet field and a field winding are proposed, the demagnetization control is unnecessary and the control malfunction at high speed adversely affects the battery etc. It is said that a field winding type synchronous machine (including a combined type in the present specification) that can be easily avoided is preferable.

In addition, the field winding type synchronous machine of this kind is regarded as a promising rotary machine for generating running power not only in ordinary engine vehicles and hybrid vehicles but also in battery-driven electric vehicles and fuel cell vehicles. .

However, the above field winding type synchronous machine is required to generate a large torque when starting an engine or climbing a vehicle when used as a hybrid vehicle, or to generate a large output when traveling at a high speed when used as an electric vehicle. Since there is a conventional alternator (output several hundred W
It is necessary to generate a remarkably large output (several + kW) as compared with the conventional alternator. Therefore, it is necessary to pass a remarkably large field current to the field winding as compared with the conventional alternator. However, in the vehicular generator-motor device that uses this field winding type synchronous machine, the field current switch that controls the field current may possibly fail to turn on (always on). When operating with a relatively large duty ratio, it is not easy to easily detect this ON failure, and as a result, a field current different from the field current value calculated by the controller based on the required output flows and In addition to the possibility that the torque may fall out of control and the operating condition may become abnormal, the discharge or charging load of the battery may become excessive, or the temperature of the field winding may increase abnormally.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and a solution thereof is to provide a vehicular generator-motor apparatus in which the reliability of the entire apparatus is significantly improved as compared with the conventional apparatus by slightly complicating the apparatus configuration. It should be an issue.

[0007]

A generator / motor device for a vehicle using a field winding type synchronous machine according to claim 1 has a field winding and an armature winding and is mounted on a vehicle as a generator / motor. A three-phase vehicle synchronous machine that operates, and is arranged between the vehicle synchronous machine and a battery to perform orthogonal bidirectional power conversion and control an armature current of the vehicle synchronous machine, and the battery. Control unit for controlling the field current fed from the power supply to the field winding and for controlling the current control unit according to a required target value to control the field current and the armature current. In a vehicular generator-motor device using a field winding type synchronous machine, the field current is a switching element for controlling the field current among switching elements for a large current constituting the current control section. Switch only multiple Because characterized in that it constitutes a switching element connected in series, it is possible to realize a vehicular generator motor apparatus remarkably improved compared with the prior art only for the entire device by complicated reliability of the device configuration.

A more detailed description will be given below.

In the vehicular generator-motor device using the three-phase field winding type synchronous machine, which is symmetrical to the present invention, conventionally, a total of seven large currents such as armature currents and field currents are interrupted in order to interrupt the large currents. A switching element for interruption has been used.
Six of them are used for three-phase inverter, and the remaining one
The individual is used as a field current switch.

If the failure probability of these seven switching elements is η, the failure probability of the vehicular generator-motor apparatus due to the failure of the switching elements should be 7η, and the failure occurrence probability of each switching element is equal. Therefore, in order to reduce the failure probability of the vehicular generator-motor apparatus due to the failure of the switching elements, it is necessary to uniformly reduce the failure probabilities of all of these seven switching elements.

However, the failure mode of the switching element that causes damage to other equipment such as winding insulation failure and battery damage is an on failure (always on) rather than an off failure (always off). Considering this on-failure as an inverter that controls the armature current, even if any one of the six switching elements forming the three-phase inverter is on-failed, the armature winding has a total of two inverters. Since the two switching elements are connected in series with the battery, the inverter is not adversely affected unless these two switching elements are simultaneously turned on. Of course, the probability that two switching elements will turn on at the same time is approximately η · η
It is extremely small and can be almost ignored.

That is, although the vehicular generator-motor apparatus using the field winding type synchronous machine has a total of seven switching elements for interrupting a large current, an adverse effect on the apparatus due to the ON failure of six of the switching elements. Can be neglected relatively, and only the ON failure of the switching element for controlling the field current (also referred to as the field current switch) has a serious adverse effect on the device.

Therefore, in this configuration, only the field current switch is constituted by a plurality of switching elements connected in series, and the total ON failure probability thereof is close to the total ON failure probability of other switching elements for armature current control. Decrease to the value. In this way, the failure occurrence probability of the entire device can be greatly reduced by a simple circuit modification in which a small number of switching elements are added, and a device with excellent reliability can be realized.

According to a second aspect of the present invention, in the vehicular generator-motor apparatus using the field winding type synchronous machine of the first aspect, the field current switch further includes a pair of switching elements connected in series. It is characterized by being configured.

As a result, the failure occurrence probability of the entire device can be greatly reduced (η · η) by a simple circuit modification in which only one switching element is added, and a device with excellent reliability can be realized. .

According to a third aspect of the present invention, in the vehicular generator-motor apparatus using the field winding type synchronous machine according to the second aspect, the pair of switching elements of the field current switch are opened / closed by the same control signal. It is characterized by that.

As a result, it is not necessary to change the control circuit configuration and the circuit configuration is simplified.

According to a fourth aspect of the present invention, in the vehicular generator-motor apparatus using the field winding type synchronous machine according to the second aspect, one of the pair of switching elements of the field current switch is always turned on and the other is turned on. PWM by control voltage
It is characterized by alternately having a controlled period and a period in which one is PWM-controlled by a control voltage and the other is always on at predetermined intervals.

According to this structure, it is possible to reduce the power loss of the entire field current switch while suppressing the increase of the field current at the time of ON failure.

According to a fifth aspect of the present invention, in the vehicular generator-motor apparatus using the field winding type synchronous machine according to the second aspect, the current control section further includes a three-phase inverter for controlling the armature current. In the inverter, three power modules each having an upper arm side switching element and a lower arm side switching element of the same phase are connected in parallel, and an AC output terminal of each power module is connected to the field winding type synchronous machine. The field current switch is configured to be individually connected to the armature winding, and the field current switch uses a power module having the same configuration as the power module in an AC output terminal floating state.

According to this structure, the number of kinds of required parts can be reduced, and manufacturing and maintenance management can be facilitated.

According to a sixth aspect of the present invention, there is provided a three-phase vehicular synchronous machine having a field winding and an armature winding, which is mounted on a vehicle and operates as a generator motor, and a switching element. A field disposed between a vehicle synchronous machine and a battery for performing orthogonal bidirectional power conversion, controlling an armature current of the vehicle synchronous machine, and being fed from the battery and flowing to the field winding. A field winding type synchronous machine including a current control unit for controlling a magnetic current and a control unit for controlling the current control unit to adjust the field current and the armature current according to a required target value is used. In the vehicular generator-motor device, the control unit controls the armature current at a timing at which overlapping of ON periods of the PWM-controlled armature current control switching element and the field current control switching element is reduced. It is characterized by setting the ON period of patronage of the switching element ON period of the switching elements of the field current control.

In a preferred embodiment, the center point of the time axis of the ON period when the PWM-controlled switching element for armature current control (switching element of the inverter) is interrupted at the carrier cycle is the PWM-controlled field. When the switching element for controlling current (field current switch) is interrupted at the same carrier period, the timing is different from the center point of the time axis of the ON period, preferably 180 degrees different phase (1/2).
It opens and closes at different timings of the carrier cycle. In another preferred aspect, the timing at which the PWM-controlled field current control switching element (field current switch) is turned on is the PWM-controlled armature current control switching element (field current switch). Coincides with the timing when is turned off. In another preferred aspect, a switching element (field current switch) for PWM-controlled field current control is provided.
Is turned on when the switching element (field current switch) for PWM-controlled armature current control is turned on.

With this configuration, the high frequency switching power generated by the current control unit can be reduced, so that the smoothing capacitor can be downsized and its heat generation can be reduced.

According to a seventh aspect of the present invention, in the vehicular generator-motor apparatus using the field winding type synchronous machine according to the second aspect, one of the pair of switching elements of the field current switch is always turned on and the other is turned on. It is characterized by being PWM-controlled and turning off the one switching element when the other switching element fails on.

According to this structure, the means for detecting the ON failure is required, but when this ON failure does not occur, one of the pair of switching elements of the field current switch can be always turned ON. , It is possible to reduce the switching loss during transient of the field current switch.

According to an eighth aspect of the present invention, in the vehicular generator-motor apparatus using the field winding type synchronous machine according to the second aspect, one of the pair of switching elements of the field current switch is always turned on and the other is turned on. In addition to PWM control, the other switching element is turned on when the other switching element fails to turn on, and the other switching element is PWM controlled.

According to this structure, the means for detecting the above-mentioned on-failure is required, but when this on-failure does not occur, one of the pair of switching elements of the field current switch can be always turned on. The switching loss of the field current switch during transition can be reduced, and further, the PWM control of the field current can be carried out without trouble even after the occurrence of the ON failure.

According to a ninth aspect of the present invention, in the vehicular generator-motor apparatus using the field winding type synchronous machine according to the first aspect, further, the pair of switching elements of the field current switch is the field winding. Since they are arranged on both sides of, the current can be safely cut off both at the time of the ground fault and at the time of the power fault of the field winding or the wiring connecting the field winding and the switching element.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION The preferred embodiments of the present invention will be described with reference to the following examples.

(Overall Structure) FIG. 1 is a block diagram showing an embodiment of a vehicular generator-motor apparatus using a field winding type synchronous machine of the present invention.

Reference numeral 1 is a field winding type synchronous machine forming a vehicular generator-motor, 2 is a current control circuit (current control section), 3 is a controller (control section), 4 is a high voltage battery (battery), and 5 is a low voltage battery. is there.

The field winding type synchronous machine 1 includes a three-phase armature winding 11 wound around a stator core, a field winding 12 wound around a rotor core, and a magnetic pole position sensor 13 for detecting a rotor angular position. Although it has a flywheel diode 14 that is connected in anti-parallel with the field winding 11, the structure itself is a normal field winding type synchronous machine, and therefore a further detailed description is omitted.

The current control circuit 2 detects a three-phase inverter 21 composed of six power MOS transistors (switching elements) 211 to 216, a field current switch 22 having a high side switch structure, and an armature current. Although the current sensor 23 and the smoothing capacitor 24 connected in parallel with the high voltage battery 4 are provided, the circuit configuration itself is already well known, and a further detailed description will be omitted.

The controller 3 includes a controller 31 having a built-in microcomputer and PWM voltages G1 to G7 of respective duties corresponding to respective command values of the field current and the armature current from the controller.
Is a drive circuit for converting each of the power MOS transistors 211 to 216 and the field current switch 22. However, since the circuit configuration itself is already well known, further detailed description will be omitted. In addition, G1 to G6 are each power M of the inverter 21.
The PWM control voltage applied to the gate terminals of the OS transistors 211 to 216, and G7 is the PWM control voltage applied to the gate terminal of the field current switch 22.

The control of the three-phase armature current and the control of the field current switch 22 by the control of the inverter 21 performed by the controller 3 are essentially the same as those of the conventional field winding type synchronous machine and are well known. Therefore, the description is omitted.

However, in this embodiment, the field current switch 22 is composed of two power MOS transistors 221 and 222 connected in series, and the gate terminals of the power MOS transistors 221 and 222 have the same PWM.
The control voltage G7 is applied.

In this way, the field current switch 22
Only a pair of power MOS transistors 2 that operate in the same manner
21 and 222 are connected in series, the adverse effect on the device due to the ON failure of the field current switch 22 which has the greatest failure effect in the entire device is reduced, and the reliability of the entire device is improved by a simple method. It can be improved significantly.

(Modification) In the above embodiment, the field current switch is composed of a pair of power MOS transistors 221 and 222.
However, other types of transistors may be adopted, and the pair of power MOS transistors 221 and 222 may be individually arranged on both sides of the field winding.
The OS transistors 221 and 222 may be arranged on the low side.

(Modification) Power MOS transistor 2
21, 222 is a period in which one is always on and the other is PWM controlled by the control voltage, and one is PW by the control voltage.
Periods in which the M control is performed and the other is always on may be alternately provided at predetermined intervals. In this way, the power MOS
It is possible to reduce the power loss and heat generation of the transistors 221 and 222 during the switching transition period, and to suppress the increase of the field current when one of the power MOS transistors 221 and 222 has an ON failure.

(Modification) Further, a pair of power MOS transistors 221, 222, a pair of power MOS transistors 211, 214, a power MOS transistor 21.
2, 215 pair, power MOS transistor 213,
If each pair of 216 is packaged in a module of the same shape, the number of types of parts can be reduced, which simplifies manufacturing and maintenance management.

(Modification) Each power M of the inverter 21
As the PWM control method for the OS transistors 211 to 216, known methods can be adopted. That is,
A method of PWM controlling the power MOS transistor on the upper arm side and the power MOS transistor on the lower arm side, a method of always turning on one arm, or a two-phase modulation method can be adopted.

(Modification) Power MOS transistor 2
21 is always turned on, the power MOS transistor 222 is PWM-controlled, and the power MOS transistor 222 is detected by a detection signal of the current sensor 23, by detecting a field current, or by another method.
It is possible to turn off the power MOS transistor 221 when the ON failure is detected. With this configuration, one of the pair of switching elements of the field current switch can be constantly turned on when the on-failure does not occur, so that the transient switching loss of the field current switch can be reduced.

(Modification) Power MOS transistor 2
21 is always turned on, the power MOS transistor 222 is PWM-controlled, and the power MOS transistor 222 is detected by a detection signal of the current sensor 23, by detecting a field current, or by another method.
When the ON failure is detected, the power MOS transistor 221 can be constantly turned on and the power MOS transistor 221 can be PWM-controlled. In this way, when no ON failure occurs, one of the pair of switching elements of the field current switch can be turned on at all times, so that the transient switching loss of the field current switch can be reduced. Even after the occurrence of the ON failure, the PWM control of the field current can be carried out without any trouble.

[0045]

Second Embodiment Another embodiment of the present invention will be described below. In this embodiment, in the device shown in FIG. 1, the ON period T1 of the PWM control voltages G1 to G6 for PWM controlling the power MOS transistors 211 to 216 and the ON period of the PWM control voltage G7 for PWM controlling the field current switch 22. T
The feature is that 2 and 1 are shifted by 1/2 PWM cycle (see FIG. 2). However, it is assumed that the PWM cycles of both are the same. With this configuration, the high-frequency power component required by the current control circuit unit 2 for the high-voltage battery 4 and the smoothing capacitor 24 can be significantly reduced as compared with the case where the on-cycles of the both PWM control voltages overlap. High voltage battery 4
Also, the life of the smoothing capacitor 24 can be extended and the loss can be reduced.

In this embodiment, the field current switch 22 may be formed by a single switching element.

(Modification) A modification is shown in FIG. In this mode, since the off timing of the PWM control voltage of the power MOS transistors 211 to 216 and the on timing of the PWM control voltage of the power MOS transistors 221 to 222 are matched, the same effect can be obtained.

(Modification) A modification is shown in FIG. In this mode, the field coil 12 of the field winding type synchronous machine 1 and the power MOS transistors 221 and 222 of the current control circuit 2 are included.
Are connected by wire harnesses 41 and 42, and the diode 14 is interposed between the power MOS transistors 221 and 222 of the current control circuit 2 in the illustrated direction.

In this way, the wire harness 41,
Even if 42 is grounded or short-circuited as shown by the broken line in FIG. 4, the current can be interrupted by either of the power MOS transistors 221 and 222. The diode 14 is a flywheel diode of the field coil 12 and does not increase the number of parts and complicate the configuration.

[Brief description of drawings]

FIG. 1 is a block circuit diagram showing a circuit configuration of a vehicular generator-motor device using a field winding type synchronous machine of the present invention.

FIG. 2 is a timing chart showing phases of PWM control voltages G1 to G7.

FIG. 3 is a timing chart showing phases of PWM control voltages G1 to G7.

FIG. 4 is a circuit diagram showing a modification.

[Explanation of symbols]

1 Field winding type synchronous machine 2 Current control circuit (current control section) 3 controller (control unit)

Claims (9)

[Claims] 1. A three-phase vehicle synchronous machine that has a field winding and an armature winding and is mounted on a vehicle to operate as a generator motor, and is arranged between the vehicle synchronous machine and a battery. A current controller that performs quadrature bidirectional power conversion and controls the armature current of the vehicular synchronous machine, and controls the field current that is fed from the battery and flows through the field winding. A control unit that controls the current control unit according to a target value to adjust the field current and the armature current, and a generator / motor device for a vehicle using a field winding type synchronous machine, the current control unit Among the switching elements for large current constituting the above, only the field current switch, which is the switching element for controlling the field current, is configured by connecting a plurality of switching elements in series. Using a synchronous machine Generator / motor device for vehicles. 2. A vehicular generator-motor apparatus using a field winding type synchronous machine according to claim 1, wherein the field current switch is composed of a pair of switching elements connected in series. Generator-motor device for vehicles using a field winding type synchronous machine. 3. A vehicular generator-motor apparatus using a field winding type synchronous machine according to claim 2, wherein the pair of switching elements of the field current switch are opened and closed by the same control signal. A generator-motor device for a vehicle using a field winding type synchronous machine. 4. A vehicular generator-motor apparatus using a field winding type synchronous machine according to claim 2, wherein one of the pair of switching elements of the field current switch is always on and the other is PWM controlled by a control voltage. And a period in which one is PWM-controlled by a control voltage and the other is always on at predetermined intervals alternately, a vehicular generator-motor device using a field winding type synchronous machine. 5. A vehicular generator-motor apparatus using the field winding type synchronous machine according to claim 2, wherein the current control section has a three-phase inverter for controlling the armature current, and the inverter is Three power modules with built-in upper arm side switching elements and lower arm side switching elements of the same phase are connected in parallel, and the AC output terminals of each power module are individually connected to the armature windings of the field winding type synchronous machine. A power generator motor device for a vehicle using a field winding type synchronous machine, wherein the field current switch uses a power module having the same configuration as the power module in an AC output terminal floating state. 6. A three-phase vehicle synchronous machine which has a field winding and an armature winding and which is mounted on a vehicle and operates as a generator motor, and a synchronous element for a vehicle and a battery which have a switching element. A current that is disposed between the field winding and the quadrature bidirectional power conversion and controls the armature current of the vehicular synchronous machine, and that controls the field current supplied from the battery and flowing to the field winding. A vehicular generator-motor device using a field winding type synchronous machine, comprising: a control unit; and a control unit that controls the current control unit according to a required target value to adjust the field current and the armature current. In the above, the controller may switch the armature current control switch at a timing at which overlapping of ON periods of the PWM-controlled armature current control switching element and the field current control switching element is reduced. A generator-motor device for a vehicle using a field winding type synchronous machine, wherein an ON period of a switching element for controlling a field current and an ON period of a switching element for controlling a field current are set. 7. A vehicular generator-motor apparatus using a field winding type synchronous machine according to claim 2, wherein one of a pair of switching elements of the field current switch is always turned on and the other is PWM-controlled. A generator / motor device for a vehicle, wherein the one switching element is turned off when the other switching element fails in an on state. 8. A vehicular generator-motor apparatus using a field winding type synchronous machine according to claim 2, wherein one of a pair of switching elements of the field current switch is always turned on and the other is PWM-controlled. A vehicular generator-motor device, wherein when the other switching element fails to turn on, the other switching element is turned on and the other switching element is PWM-controlled. 9. A vehicular generator-motor apparatus using a field winding type synchronous machine according to claim 1, wherein the pair of switching elements of the field current switch are arranged on both sides of the field winding. Characteristic vehicle generator motor device.