JP7182641B2 - Drive system and control method - Google Patents

Description

The present invention relates to a drive system for driving a rotating electrical machine, and more particularly to a system for driving a rotating electrical machine having two independent Y-connections.

As a background art of this technical field, there is Japanese Patent Laying-Open No. 2013-215040 (Patent Document 1). Japanese Patent Application Laid-Open No. 2013-215040 states that “when the failure detection means detects a failure of the inverter unit in the first system, the drive control means stops driving the inverter unit. Turn off the first power relay of the power switching unit and turn on the second power relay.When the inverter unit is not driven, the induced voltage generated in the first winding set of the motor due to the rotation by the external force is generated by the inverter unit. from the second power relay, and then through the parasitic diode of the first power relay to regenerate to the battery.This prevents damage to the circuit elements of the faulty system.(See abstract)".

JP 2013-215040 A

However, the aforementioned prior art (Patent Document 1) aims at preventing damage to circuit elements in a failed system, and does not consider continuation of operation with the failed phase isolated.

A representative example of the invention disclosed in the present application is as follows. That is, in the drive system, for operating a rotating electric machine having a first system of windings Y-connected and a second system of windings Y-connected independently of the first system of windings. and a control device for outputting a control signal to the inverter circuit, wherein the drive system controls any phase winding of the windings of the first system. When an abnormality occurs in the current flowing through the winding of the first system, the current supplied from the inverter circuit is supplied to the winding of the first system so that a first single-phase circuit is configured by the other plurality of phases of the winding of the first system. The current waveform supplied from the inverter circuit is supplied from the inverter circuit to the second system so that a second single-phase circuit is configured by controlling the flowing first current waveform and stopping the current of one of the phases of the windings of the second system. The second current waveform flowing through the winding is controlled to have a phase different from the first current waveform , and the combined power obtained by combining the powers in the first single-phase circuit and the second single-phase circuit is converted into mechanical output The current phase of the first single-phase circuit and the current phase of the second single-phase circuit are controlled so that the electric power becomes constant.

According to one aspect of the present invention, operation can be continued until one phase fails in each system. Problems, configurations, and effects other than those described above will be clarified by the following description of the embodiments.

1 is a diagram showing the configuration of a rotating electric machine drive system and a rotating electric machine according to a first embodiment; FIG. FIG. 10 is a diagram showing the configuration of the rotary electric machine drive system and the rotary electric machine of Example 2; FIG. 10 is a diagram showing the configuration of a rotating electric machine drive system and a rotating electric machine according to a third embodiment; FIG. 4 is a diagram showing changes in no-load induced voltage of a rotating electrical machine in normal conditions; FIG. 4 is a diagram showing currents flowing through windings of each system when U-phase is stopped; FIG. 4 is a diagram showing the power of each system when the U-phase is stopped; FIG. 4 is a diagram showing currents flowing through the windings of each system when different phases are stopped in the first system and the second system; FIG. 4 is a diagram showing the power of each system when different phases are stopped in the first system and the second system; FIG. 4 is a diagram showing changes in no-load induced voltage of a rotating electrical machine in normal conditions; FIG. 4 is a diagram showing currents flowing through the windings of each system when different phases are stopped in the first system and the second system; FIG. 4 is a diagram showing the power of each system when different phases are stopped in the first system and the second system;

<Example 1>
FIG. 1 is a diagram showing the configuration of a rotating electric machine drive system and a rotating electric machine according to a first embodiment of the present invention.

The rotary electric machine drive system of the first embodiment is connected to a rotary electric machine 100 used in a hybrid vehicle (HEV), an electric vehicle (EV), or the like, and controls driving of the rotary electric machine 100 . The rotating electric machine 100 is a motor for driving the vehicle and a motor for operating each part of the vehicle (for example, power steering, door opening/closing). The rotary electric machine drive system has a DC power supply 201 , a smoothing capacitor 202 , a control microcomputer 203 , a drive circuit 204 and an inverter circuit 210 .

The rotary electric machine 100 is a three-phase AC rotary electric machine with two independent systems and a Y-connection. That is, rotating electric machine 100 includes three-phase armature windings _102u1 , _102v1 , and _102w1 corresponding to U1 _- phase, V1 _- phase, and _W1- phase of the first system, respectively, and _U2 of the second system. It has three-phase armature windings 102 _u2 , 102 _v2 , and 102 _w2 respectively corresponding to phases V ₂ and W ₂ . Since the armature windings 102 _u to 102 _w of each system are provided independently of each other, different currents can flow in each phase. Armature windings are connected at neutral points n ₁ and n ₂ for each system. Neutral points n ₁ and n ₂ may be provided inside rotating electric machine 100 as illustrated, but may be provided outside.

Inverter circuit 210 drives rotating electric machine 100 by independently controlling currents flowing through armature windings 102 _u to 102 _w . A position detection unit 110 that detects the magnetic pole position of the rotating electrical machine 100 is attached to the output shaft of the rotating electrical machine 100 . A detection result of the magnetic pole position by the position detection unit 110 is output to the control microcomputer 203 .

DC power supply 201 supplies DC power to inverter circuit 210 via DC buses 201a and 201b. A secondary battery such as a lithium ion battery can be used for the DC power supply 201, for example.

The smoothing capacitor 202 is for absorbing fluctuations in the DC voltage caused by the operation of the inverter circuit 210, and is connected in parallel with the inverter circuit 210 between the DC bus 201a and the DC bus 201b.

The control microcomputer 203 performs predetermined current control calculations, and based on the results of the calculations, outputs control signals that instruct the output voltage and output current of each phase to the drive circuit 204 . The drive circuit 204 outputs drive signals G _u1 , G _v1 and G _w1 to the bridge circuits 211 _u1 , 211 _v1 and 211 _w1 of each phase of the inverter circuit 210, respectively. The control microcomputer 203 controls the inverter circuit 210 through the drive circuit 204 by operating the bridge circuits 211 _u1 , 211 _v1 and 211 _w1 according to the drive signals G _u1 , G _v1 and G _w1 .

The inverter circuit 210 has bridge circuits 211 _u1 , 211 v1 , and 211 _w1 respectively corresponding to the U-phase, V- _phase , and W-phase of the first system. Each bridge circuit 211 _u1 , 211 _v1 , 211 _w1 has IGBTs functioning as switching elements for upper and lower arms, and diodes provided in parallel with each IGBT. In the bridge circuits 211 _u1 , 211 _v1 , 211 _w1 , the respective IGBTs perform switching _{operations according to the drive signals Gu1 , G v1 ,} G _w1 from the drive circuit 204 . As a result, the DC power supplied from the DC power supply 201 is converted into three-phase AC power, which is supplied from the bridge circuits _211u1 , _211v1 , and _211w1 to the respective phases of the rotary electric machine 100 via the AC output lines 120 of each phase. An alternating current is output to each of the armature windings 102 _u1 , 102 _v1 and 102 _w1 .

A current sensor 130 for detecting each current flowing through the armature windings 102 _u1 , 102 _v1 , 102 _w1 of the rotary electric machine 100 is provided on the AC output line 120 of each phase. In the illustrated example, the current sensor 130 is provided inside the inverter circuit 210, but may be provided outside. A current value of each phase detected by the current sensor 130 is output to the control microcomputer 203 . The control microcomputer 203 performs predetermined current control based on the user's operation or a control command input from another ECU, the current value of each phase input from the current sensor 130, and the detection of the magnetic pole position by the position detection unit 110. A calculation is performed, and based on the result of the calculation, a control signal is output that instructs the drive circuit 204 to output the drive signals G _u1 , G _v1 , and G _w1 for each phase.

The operations of the control microcomputer 203, the drive circuit 204, and the inverter circuit 210 have been described above for the first system, but the second system also operates in the same manner.

When the control microcomputer 203 detects an abnormality in the U1-phase current based on the measurement value of the current sensor 130 of the U-phase ( _{U1 -} phase) of the first system, the control microcomputer 203 controls the other phase ( _V1 The currents flowing through the V1-phase and _W1- phase windings are controlled so that the windings of the V1 _- phase and _W1- phase) constitute a first single-phase H-bridge circuit. Similarly, in the second system, the control microcomputer 203 also controls the V 2 _- phase and W ₂ -phase windings so that the windings of the corresponding phases (V _2- phase, W _2- phase) constitute the second single-phase H bridge circuit. controls the current flowing through the windings of the That is, the first single-phase circuit includes a two-phase coil in which V1 _- phase and _W1 -phase windings other than the faulty phase are connected in series via a neutral point, and V1 _- phase and W1 _- phase of inverter circuit 210. It consists of an H-bridge circuit with phase transistors. Similarly, the second single-phase circuit includes a two-phase coil in which V2 _- phase and W2-phase windings other than the stopped phase are connected in series via a neutral point, and V2 _- phase and W2 _- phase of the inverter circuit 210. It is composed of an H-bridge circuit with _two- phase transistors.

An abnormal current in each phase means a state in which a current different from a normal state is flowing, such as zero current flowing in each phase winding. That is, the control microcomputer 203 controls the current and voltage of each phase so as to achieve the current target value. , the failure of the phase may be detected.

The current phases of the first single-phase circuit and the second single-phase circuit can be controlled independently. That is, the control microcomputer 203 controls the phase of the current flowing through the first single-phase circuit and the phase of the current flowing through the second single-phase circuit so that the total power of the two single-phase circuits is constant. Specifically, when the rotary electric machine drive system (control microcomputer 203) detects a failure of one phase of one of the two systems, it stops one phase of the normal system and separates each system into an independent single phase. A phase H bridge circuit (first single-phase circuit, second single-phase circuit) is configured, and the current phase flowing in the first single-phase circuit and the second single-phase circuit are adjusted so that the total power of the two single-phase circuits is constant. Controls the phase of current flowing in a single-phase circuit.

As described above, in the rotary electric machine drive system of the first embodiment, the rotary electric machine 100 can be continuously operated until one phase of each system fails. At this time, the phase of the current _Ivw1 flowing in the windings of the first system and the second By controlling the phase of the current _Ivw2 flowing through the windings of the system, power with suppressed pulsation can be supplied to the rotating electric machine 100, and torque with little pulsation can be generated.

<Example 2>
FIG. 2 is a diagram showing the configuration of a rotating electric machine drive system and a rotating electric machine according to a second embodiment of the present invention. In the second embodiment, differences from the first embodiment will be explained, and the same reference numerals will be given to the same configurations as in the first embodiment, and the explanation thereof will be omitted.

The rotary electric machine drive system of the second embodiment is connected to a rotary electric machine 100 used in a hybrid vehicle (HEV), an electric vehicle (EV), or the like, and controls driving of the rotary electric machine 100 . The rotary electric machine drive system has a DC power supply 201 , a smoothing capacitor 202 , a control microcomputer 203 , a drive circuit 204 and an inverter circuit 210 .

The rotating electrical machine 100 of the second embodiment _is a three-phase AC rotating electrical machine with two independent systems and _a Y connection. has a neutral point relay 140 controlled by Neutral point relay 140 may be provided inside rotating electric machine 100 as illustrated, but may be provided outside. For example, when neutral points n ₁ and n ₂ are provided outside rotating electrical machine 100 , neutral point relay 140 is provided outside rotating electrical machine 100 .

The control microcomputer 203 controls the neutral point relay 140 to open the contacts in order to cut off the current flowing through the phase ( _U1 phase) in which the abnormality has occurred. Similarly, the control microcomputer 203 controls the neutral point relay 140 to open the contact in order to cut off the current flowing in the corresponding phase ( _U2 phase) in the normal system.

As described above, in the rotary electric machine drive system of the second embodiment, the neutral point relay 140 opens the winding of the second system corresponding to the failed phase and the neutral point. It is possible to prevent the current due to the induced voltage generated by the interlinkage between the magnetic flux of the magnet and the winding in the stopped phase.

<Example 3>
Embodiment 3 FIG. 3 is a diagram showing the configuration of a rotating electrical machine drive system and rotating electrical machine according to a third embodiment of the present invention. In Example 3, differences from Example 1 will be explained, and the same components as those in Example 1 will be given the same reference numerals, and their explanation will be omitted.

The rotary electric machine drive system of the third embodiment is connected to a rotary electric machine 100 used in a hybrid electric vehicle (HEV), an electric vehicle (EV), or the like, and controls driving of the rotary electric machine 100 . The rotary electric machine drive system has a DC power supply 201 , a smoothing capacitor 202 , a control microcomputer 203 , a drive circuit 204 and an inverter circuit 210 .

The rotary electric machine 100 of the third embodiment is a three-phase AC rotary electric machine with two independent systems and a Y connection. has 150. Relay 150 may be provided outside rotating electric machine 100 as illustrated, but may be provided inside.

As described above, in the rotating electric machine drive system of the third embodiment, the relay 150 opens between the winding of the second system corresponding to the failed phase and the inverter circuit 210 to stop the second system. It is possible to prevent the current due to the induced voltage generated by the interlinkage between the magnetic flux of the magnet and the winding in the phase.

<Voltage waveform, current waveform, power waveform>
Next, voltage waveforms, current waveforms, and power waveforms under the control of the above embodiment will be described.

FIG. 4 is a diagram showing changes in the no-load induced voltage of rotating electrical machine 100 during normal operation. The relationship between the electrical angle and the phase of the induced voltage in the windings of each phase depends on the configuration of the windings of the rotating electrical machine 100. different currents flow.

<Control to stop the same phase>
First, the control for stopping the same phase in the first system and the second system will be described. The control microcomputer 203 stops the U-phase and operates the V-phase and W-phase in the first and second systems. Then, a current having a phase shown in FIG. 5 is passed through each system. In this case, the power of each system changes as shown in FIG. 6, and the combined power _{P_in} of the first system and the second system is converted into a mechanical output obtained by subtracting the copper loss and the reactive power. The power can be controlled to be constant.

A voltage equation of the first system of the rotating electric machine 100 during normal operation is represented by Equation 1, and a voltage equation of the second system is represented by Equation 2. In the following equations, v _u1N , v _v1N , and v _w1N are the terminal voltages of the U-phase, V-phase, and W-phase windings of the first system, respectively, and v _u2N , v _v2N , and v _w2N are the second system are the terminal voltages of the U-phase, V-phase, and W-phase windings. Ri _u1 , Ri _v1 , Ri _w1 , Ri _u2 , Ri _v2 , and Ri _w2 are the winding resistances, and L is the winding inductance. i _u1 , i _v1 , and i _w1 are the currents flowing through the U-phase, V- _{phase ,} and _W- phase windings of the first system, respectively; This is the current that flows through the V-phase and W-phase windings. e _u1n1 , e _v1n1 and e _w1n1 are the no-load induced voltages of the U phase, V phase and W phase of the first system, respectively, and e _u2n2 , e _v2n2 and e _w2n2 are the U phase and V phase of the second system, respectively. and W-phase no-load induced voltages.

Also, the voltage equation of the first system when the U-phase is missing is expressed by Equation 3. In the following equation, v _vw1 is the voltage output to the winding from the first single-phase circuit composed of the V and W phases, and i _vw1 is the first single phase circuit composed of the V and W phases. It is the current flowing in the single-phase circuit, and the other parameters are the same as in the previous equation.

Similarly, the voltage equation of the second system when the U phase is missing is expressed by Equation 4. In the following equation, v _vw2 is the voltage output to the winding from the second single-phase circuit composed of the V and W phases, and i _vw2 is the second single phase circuit composed of the V and W phases. It is the current flowing in the single-phase circuit, and the other parameters are the same as in the previous equation.

The input power _{Pvw1_in} of the first system when the U phase is lost is expressed by Equation 5, and the input power _{Pvw2_in} of the second system when the U phase is lost is expressed by Equation 6. The parameters in Equations 5 and 6 are the same as in the previous equations. In the second line of Equations 5 and 6, the first term represents copper loss, the second term represents reactive power, and the third term represents mechanical output.

Power P _{_in} input to rotating electric machine 100 is the sum of input power P _{vw1_in} of the first system and input power P _{vw2_in} of the second system, as shown in Equation 7. As shown in Equation 8, the mechanical output _{P_out} of the rotating electrical machine 100 is a value obtained by subtracting the copper loss and the reactive power from the sum of the input power of the first system and the input power of the second system. Then, the control microcomputer 203 controls the input power _{P_in} of the rotating electric machine 100 so that the power that is converted into the mechanical output obtained by subtracting the copper loss and the reactive power from the input power P_in flows through the windings of the first system. It controls the phase of the current i _vw1 and the phase of the current i _vw2 flowing through the windings of the second system. Thereby, the mechanical output _{P_out} of the rotary electric machine 100 can be made constant. The torque output by the rotary electric machine 100 is a value obtained by dividing the mechanical output by the angular velocity of the shaft, as shown in Equation (9). Therefore, by controlling the input electric power _{P_in} of the rotating electrical machine 100 to be constant, the output torque can be controlled to be constant when the rotating electrical machine 100 rotates at a constant speed.

When the two single-phase circuits are configured as described above, the phase to be stopped in the normal second system may be changed according to the configuration of the windings of the rotating electrical machine 100 . For example, if the windings of the rotating electric machine 100 are distributed windings, it is preferable to stop the phase that is the same as the phase that has failed in the first system also in the second system. Specifically, when an abnormality occurs in the U phase in the first system, the U phase in the second system is also stopped. On the other hand, if the winding of the rotary electric machine 100 is concentrated winding, it is preferable to stop the phase different from the failed phase in the first system in the second system. Specifically, when an abnormality occurs in the U phase in the first system, the V phase or W phase is stopped in the second system.

<Control to stop different phases when there is a phase difference between systems>
Next, referring to FIGS. 7 and 8, control for stopping different phases between the first system and the second system when there is a phase difference between the first system and the second system as shown in FIG. explain.

The control microcomputer 203 stops the U phase and operates the V and W phases in the first system, and stops the V phase and operates the W and U phases in the second system. Then, a current having a phase shown in FIG. 7 is passed through each system. In this case, the power of each system changes as shown in FIG. 8, and the combined power _{P_in} of the first system and the second system is converted into a mechanical output obtained by subtracting the copper loss and the reactive power. The power can be controlled to be constant.

<Control to stop different phases when there is no phase difference between systems>
Next, referring to FIGS. 9, 10 and 11, when there is no (or extremely small) phase difference between the first system and the second system as shown in FIG. A description will be given of the control for stopping different phases in and . In the rotating electric machine 100, as shown in FIG. 9, the windings of the first system and the second system are configured such that there is no phase difference between the same phases, and no-load induced voltages of the same phase are applied to the same phases. occur.

The control microcomputer 203 stops the W phase and operates the U and V phases in the first system, and stops the V phase and operates the W and U phases in the second system. Then, a current having a phase shown in FIG. 10 is applied to each system. In this case, the power of each system changes as shown in FIG. 11, and the combined power _{P_in} of the first system and the second system is converted into a mechanical output obtained by subtracting the copper loss and the reactive power. The power can be controlled to be constant.

By the control described above, when one phase of each system fails, electric power that suppresses pulsation is supplied to rotating electrical machine 100, torque with little pulsation is generated, and rotating electrical machine 100 can be operated continuously.

In this embodiment, when one phase of the first system fails, the second system is operated with two phases. may

In addition, if an abnormality occurs in one of the two phases during operation while the winding of one phase of the second system is stopped and two phases are operating, the phase in which the abnormality has occurred is stopped. and should operate in two phases that are operational (including the first phase that is deactivated).

It should be noted that the present invention is not limited to the embodiments described above, but includes various modifications and equivalent configurations within the scope of the appended claims. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and the present invention is not necessarily limited to those having all the described configurations. Also, part of the configuration of one embodiment may be replaced with the configuration of another embodiment. Moreover, the configuration of another embodiment may be added to the configuration of one embodiment. Further, additions, deletions, and replacements of other configurations may be made for a part of the configuration of each embodiment.

In addition, each configuration, function, processing unit, processing means, etc. described above may be realized by hardware, for example, by designing a part or all of them with an integrated circuit, and the processor realizes each function. It may be realized by software by interpreting and executing a program to execute.

Information such as programs, tables, and files that implement each function can be stored in storage devices such as memories, hard disks, SSDs (Solid State Drives), or recording media such as IC cards, SD cards, and DVDs.

In addition, the control lines and information lines indicate those considered necessary for explanation, and do not necessarily indicate all the control lines and information lines necessary for mounting. In practice, it can be considered that almost all configurations are interconnected.

100 Rotary electric machine 102 Armature winding 110 Position detector 120 AC output line 130 Current sensor 140 Neutral point relay 150 Relay 201 DC power supply 202 Smoothing capacitor 203 Control microcomputer 204 Drive circuit 210 Inverter circuit 211 Bridge circuits n1, n2 Neutral point

Claims (6)

a drive system,
AC current of three or more phases is supplied to operate a rotating electrical machine having a first system of Y-connected windings and a second system of windings that are Y-connected independently of the first system of windings. an inverter circuit for output;
a control device that outputs a control signal to the inverter circuit;
The drive system includes:
When an abnormality occurs in the current flowing in any one of the windings of the first system, the other phases of the windings of the first system form a first single-phase circuit. , controlling a first current waveform supplied from the inverter circuit and flowing through the windings of the first system;
A second current waveform supplied from the inverter circuit and flowing through the windings of the second system so that a second single-phase circuit is configured by stopping the current of any phase of the windings of the second system. is controlled to a phase different from the first current waveform ,
The current phase of the first single-phase circuit and the second single-phase circuit are adjusted so that the power converted to mechanical output out of the combined power obtained by combining the power in the first single-phase circuit and the second single-phase circuit is constant. A drive system that controls the current phase of a phase circuit. A drive system according to claim 1, comprising:
A drive system , wherein said first current waveform and said second current waveform are sine waves with a phase difference of 210 degrees . A drive system according to claim 1, comprising:
When an abnormality occurs in the current flowing in any one of the phase windings of the first system, the supply of current to the windings of the second system of a phase different from the phase in which the abnormality occurred in the first system is stopped. drive system. A drive system according to any one of claims 1 to 3,
In the first system and the second system, a relay is provided between each phase winding and a neutral point,
A drive system that operates the relay to cut off the current flowing through the winding of the phase in which the current is abnormal. A drive system according to any one of claims 1 to 3,
In the first system and the second system, a relay is provided between each phase winding and the inverter circuit,
A drive system that operates the relay to cut off the current flowing through the winding of the phase in which the current is abnormal. A control method in which a drive system drives a rotating electric machine,
The drive system includes an inverter circuit that outputs three or more phases of alternating current to operate the rotating electric machine;
a control device that outputs a control signal to the inverter circuit;
The rotating electrical machine has a first system of windings Y-connected and a second system of windings Y-connected independently of the first system of windings,
The control device is
When an abnormality occurs in the current flowing in any one of the windings of the first system, the other phases of the windings of the first system form a first single-phase circuit. controlling a first current waveform supplied from the inverter circuit and flowing through the windings of the first system;
The waveform of the second current supplied from the inverter circuit and flowing through the windings of the second system is configured such that a second single-phase circuit is formed by stopping the current of any phase of the windings of the second system. Control to a phase different from the first current waveform ,
The current phase of the first single-phase circuit and the second single-phase circuit are adjusted so that the power converted to mechanical output out of the combined power obtained by combining the power in the first single-phase circuit and the second single-phase circuit is constant. A control method for controlling the current phase of a phase circuit.

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