JP5921031B2 - Induction machine controller - Google Patents

Description

  The present invention relates to torque control of induction machines, and in particular, avoids a step-out state during collective torque control of a plurality of induction machines.

FIG. 2 is a block diagram showing a conventional example. 101, 102, 103 and 104 are induction machines, 2 is a current detector, 3 is a power converter, 4 is torque control means, 5 is a magnetic flux calculator, and 6 is a speed calculator.
In FIG. 2, only four induction machines are shown, but any number of induction machines may be used as long as there are a plurality of induction machines. In the following description, it is assumed that there are four induction machines and the motor constants of the induction machines 101, 102, 103, and 104 are the same.

  The current detector 2 detects a total current i that is a sum of currents flowing through the individual induction machines connected to the power converter 3 for each phase. Let each induction machine input current be i1, i2, i3, i4.

  The voltage system magnetic flux calculator 5 calculates the induction machine magnetic flux φ from the total current i and the voltage command v input to the power converter 3 by the equation (1).

ここで、Ｒ１は全誘導機の一次抵抗合成値、Ｌ２は二次自己インダクタンス合成値、Ｍは相互インダクタンス合成値、Lekは漏れインダクタンス合成値である。漏れインダクタンス合成値Lekは、

Here, R1 is a primary resistance composite value of all induction machines, L2 is a secondary self-inductance composite value, M is a mutual inductance composite value, and Lek is a leakage inductance composite value. Leakage inductance composite value Lek is

で与えられる。ここで、Ｌ１は全誘導機の一次自己インダクタンス合成値である。

Given in. Here, L1 is a primary self-inductance composite value of all induction machines.

  The speed calculator 6 calculates the induction machine speed ωm from the total current i and the induction machine magnetic flux φ using the equations (3) to (5).

ここで、Ｒ２は全誘導機の二次抵抗合成値、ＦＡとＦＢは誘導機磁束φの成分である。

Here, R2 is a secondary resistance composite value of all induction machines, and FA and FB are components of induction machine magnetic flux φ.

  The induction machine speed ωm calculated by Expression (5) is an average value of the individual induction machine speeds, and is a value expressed by Expression (6).

ここで、ωｍ1は誘導機101の速度、ωｍ2は誘導機102の速度、ωｍ3は誘導機103の速度、ωｍ4は誘導機104の速度である。

Here, ωm1 is the speed of the induction machine 101, ωm2 is the speed of the induction machine 102, ωm3 is the speed of the induction machine 103, and ωm4 is the speed of the induction machine 104.

When the operation command N is ON, the torque control means 4 is based on the induction machine speed ωm and the total current i so that the magnetic flux and total torque of all induction machines become the magnetic flux command φ * and the torque command τ *. Command v is output. When the operation command N is OFF, the voltage command v is set to 0, and the induction machine is brought into an uncontrolled state.
The power converter 3 amplifies the voltage command v and supplies power to the induction machines 101 to 104 that are loads.

  The operation command N is input to the power converter 3 instead of being input to the torque control means 4, and when the operation command N is ON, power corresponding to the voltage command v is supplied to the induction machines 101 to 104, and the operation command N is OFF. Even when the power supply is stopped, the same function can be obtained.

  With the above configuration, when the operation command is ON, the total torque of the plurality of induction machines can be controlled to the torque command τ *. Moreover, since each induction machine has the same motor constant, it outputs a torque of 1/4 of the torque command τ *. If the operation command is turned off, the plurality of induction machines can be brought into an uncontrolled state.

  In vehicles, since bogie control and vehicle control are common, collective torque control of multiple induction machines is frequently used.

Japanese Patent Laid-Open No. 11-069895

The prior art has the following problems.
When some wheel shafts that are collectively controlled in the vehicle are idle, for example, when the speed ωm3 of the induction machine 103 is larger than ωm1, ωm2, and ωm4, according to equation (6), ωm1, ωm2, ωm3, A calculation error of the induction machine speed ωm with respect to ωm4 occurs. If the idler of the induction machine 103 is large and the calculation error of the induction machine speed ωm is large, the induction machine 103 is in a step-out state. Furthermore, if the idling of the induction machine 103 becomes large, not only the induction machine 103 but also the induction machine 101, the induction machine 102, and the induction machine 104 will be out of step.

  In addition, when the sliding of some wheel shafts becomes large, the induction machine may be out of step as in the case of idling.

When the induction machine goes out of step, torque control becomes impossible, and in the worst case, overcurrent and overvoltage lead to destruction of the induction machine and power converter element.
The present invention has been made to solve the above problems.

Having a plurality of induction machines, a magnetic flux calculator that calculates the induction machine magnetic flux from the total current and voltage command of all the induction machines, and a speed calculator that calculates the induction machine speed from the induction machine magnetic flux and the total current In the induction machine control device having torque control means for collectively controlling the torque of the plurality of induction machines based on the total current, the induction machine speed, the magnetic flux command, the torque command, and the operation command,
A secondary magnetic flux calculator for calculating a secondary magnetic flux of each induction machine from the current input to each induction machine and the voltage command; a current input to each induction machine and a secondary magnetic flux of each induction machine; A torque calculator for calculating the torque of each induction machine, torque difference detection means for inputting the torque of each induction machine and outputting a detection signal, and an operation logic for creating a control command from the operation command and the detection signal A new controller is added, and the control command is input to the torque control means instead of the operation command.

  According to the present invention, it is possible to detect that the idling and sliding of some wheel shafts have increased before the induction machine is out of step, and it is possible to stop the torque control of the induction machine.

It is a block diagram which shows one Example of Claim 1 of this invention. It is a block diagram which shows one prior art example. It is a figure which shows one Example of the torque difference detection means of Claim 1 of this invention.

  By newly adding the secondary magnetic flux calculator 10, the torque calculator 7, and the torque difference detection means 8, it can be detected that idling or sliding has occurred on some wheel shafts in all induction machines. The detected logic is processed by the driving logic unit 9 to create a control command and input it to the torque control means 4 to stop the torque control of the induction machine.

  FIG. 1 is a block diagram showing an embodiment of the present invention, in which 10 is a secondary magnetic flux calculator, 7 is a torque calculator, 8 is a torque difference detection means, and 9 is an operation logic unit.

  In the case of the induction machine 101, the secondary magnetic flux calculator 10 receives the current i1 inputted to the induction machine 101 and the voltage command v inputted to the power converter 3, and the induction machine is obtained from the equations (7) and (8). The secondary magnetic flux φ2v1 of 101 is calculated.

ここで、Ｒ11は誘導機101の一次抵抗値、Ｌ11は誘導機101の一次自己インダクタンス値、Ｌ21は誘導機101の二次自己インダクタンス値、Ｍ1は誘導機101の相互インダクタンス値である。

Here, R11 is the primary resistance value of the induction machine 101, L11 is the primary self-inductance value of the induction machine 101, L21 is the secondary self-inductance value of the induction machine 101, and M1 is the mutual inductance value of the induction machine 101.

  Similarly, the other induction machines have the secondary magnetic flux φ2v2 of the induction machines 102, 103, and 104 from the expressions (9), (10), (11), (12), (13), and (14). Calculate φ2v3 and φ2v4.

ここで、Ｒ12は誘導機102の一次抵抗値、Ｌ12は誘導機102の一次自己インダクタンス値、Ｌ22は誘導機102の二次自己インダクタンス値、Ｍ2は誘導機102の相互インダクタンス値、Ｒ13は誘導機103の一次抵抗値、Ｌ13は誘導機103の一次自己インダクタンス値、Ｌ23は誘導機103の二次自己インダクタンス値、Ｍ3は誘導機103の相互インダクタンス値、Ｒ14は誘導機104の一次抵抗値、Ｌ14は誘導機104の一次自己インダクタンス値、Ｌ24は誘導機104の二次自己インダクタンス値、Ｍ4は誘導機104の相互インダクタンス値である。

Here, R12 is the primary resistance value of the induction machine 102, L12 is the primary self inductance value of the induction machine 102, L22 is the secondary self inductance value of the induction machine 102, M2 is the mutual inductance value of the induction machine 102, and R13 is the induction machine. 103, the primary self-inductance value of the induction machine 103, L23 is the secondary self-inductance value of the induction machine 103, M3 is the mutual inductance value of the induction machine 103, R14 is the primary resistance value of the induction machine 104, L14 Is the primary self-inductance value of the induction machine 104, L24 is the secondary self-inductance value of the induction machine 104, and M4 is the mutual inductance value of the induction machine 104.

  The torque calculator 7 calculates the torque of each induction machine. In the case of the induction machine 101, φ2v1 calculated by the secondary magnetic flux calculator 10 and the current i1 input to the induction machine 101 are input, and the calculation torque Trq1 is calculated from Expression (15). Similarly, the other induction machines calculate the calculation torques Trq2, Trq3, and Trq4 from the equations (16), (17), and (18).

The torque difference detection means 8 receives the calculated torque of each induction machine, calculates the absolute value of the difference between the calculated torques, and outputs a detection signal K. When there are four induction machines, input Trq1, Trq2, Trq3, Trq4 and the absolute value of each difference | Trq1-Trq2 |, | Trq1-Trq3 |, | Trq1-Trq4 |, | Trq2-Trq3 |, | Trq2-Trq4 | and | Trq3-Trq4 | are calculated and a detection signal K is output.
FIG. 3 is a diagram showing an embodiment of the torque difference detecting means 8. K is turned ON if any of the absolute values of the torque differences exceeds the detection threshold TrqL, and K is turned OFF if all of the absolute values are below. .

  The detection signal K indicates that some of the wheel shafts in the plurality of induction machines are idling or sliding. TrqL and the degree of idling or sliding are linked, and if TrqL is small, detection signal K is turned OFF by a little idling or gliding. On the other hand, if TrqL is large, the detection signal K is difficult to be turned off with a slight idling or sliding.

  It is assumed that only the induction machine 103 is idle among the induction machines 101 to 104, and ωm3 becomes larger than ωm1, ωm2, and ωm4. According to Equation (6), the speed calculation errors are ωm> ωm1, ωm> ωm2, ωm> ωm4, and ωm <ωm3. As a result, the actual slips of the induction machines 101, 102, 104 increase and the actual slip of the induction machine 103 decreases with respect to the slip command ωs scheduled from the torque command τ * and the magnetic flux command φ *.

  In this state, when torque control is performed by the torque control means 4 so that the total current i is constant, the total torque matches the torque command τ *, but the magnitude of each torque is different, and the torque of the induction machine 103 is different. Becomes smaller than the torque of the induction machines 101, 102, 104, and a torque difference is generated. The magnitude of the torque of the induction machine 103 depends on the degree of idling, but if idling is large, it becomes smaller than other induction machines and the torque difference becomes large. The torque difference detection means 8 creates the detection signal K by utilizing the fact that the torque difference between the induction machines is increased in the above-described manner. Here, the idling is taken as an example, but the same applies to the case of sliding.

  The operation logic unit 9 performs an AND operation between the operation command N and the detection signal K, and outputs a control command NN. If either the operation command N or the detection signal K is OFF, the control command NN is OFF.

  When the control command NN is ON, the torque control means 4 is based on the induction machine speed ωm and the total current i, so that the voltage and total torque of all induction machines become the flux command φ * and the torque command τ *. Command v is output. When the control command NN is OFF, the voltage command v is set to 0, and the induction machine is brought into a non-control state.

  The control command NN is input to the power converter 3 instead of being input to the torque control means 4, and when the control command NN is ON, power corresponding to the voltage command v is supplied to the induction machines 101 to 104, and the control command NN is OFF. Even when the power supply is stopped, the same function can be obtained.

  By adopting the above configuration, it is possible to detect that the idling and sliding of some axles have increased before the induction machine is in a step-out state, and torque control of the induction machine can be stopped. Here, by adjusting TrqL in FIG. 3, it is possible to adjust the degree of idling and sliding of some axles that stop the torque control of the induction machine.

  This is not limited to the speed calculation error due to idling or sliding of some wheel shafts in vehicle control, but even if there is a difference in the shaft speeds of some induction machines that are subject to collective torque control. The invention is effective.

  In the control of a plurality of induction machines such as a vehicle, it is possible to detect idling and sliding of some wheel shafts. Furthermore, the induction machine control can be stopped by the detection signal K before reaching the induction machine step-out state caused by the idling and sliding of some wheel shafts.

  Not only the calculation torque difference due to idling or sliding of some wheel shafts in vehicle control, but also when there is a difference in some shaft torques of multiple induction machines that are subject to collective torque control. The induction machine control can be stopped by the detection signal K before reaching the machine step-out state.

  By stopping the induction machine control, it is possible to prevent the destruction of the induction machine and the element destruction of the power converter 3 due to the overcurrent and overvoltage caused by the induction machine step-out state.

101, 102, 103, 104 induction machine
200, 201, 202, 203, 204 Current detector 2 Current detector 3 Power converter 4 Torque control means 5 Magnetic flux calculator 6 Speed calculator 7 Torque calculator 8 Torque difference detection means 9 Driving logic 10 Secondary magnetic flux calculation vessel

i ... Total current v ... Voltage command τ * ... Torque command φ * ... Magnetic flux command ωm ... Induction machine speed φ ... Induction machine flux N ... ·Operation command
i1, i2, i3, i4 ... Input current of each induction machine φ2v1, φ2v2, φ2v3, φ2v4, ... Secondary magnetic flux of each induction machine
Trq1, Trq2, Trq3, Trq4 ... Calculation torque of each induction machine K ... Detection signal
NN ... Control command

Claims (1)

Having a plurality of induction machines, a magnetic flux calculator that calculates the induction machine magnetic flux from the total current and voltage command of all the induction machines, and a speed calculator that calculates the induction machine speed from the induction machine magnetic flux and the total current In the induction machine control device having torque control means for collectively controlling the torque of the plurality of induction machines based on the total current, the induction machine speed, the magnetic flux command, the torque command, and the operation command,
A secondary magnetic flux calculator for calculating a secondary magnetic flux of each induction machine from the current input to each induction machine and the voltage command; a current input to each induction machine and a secondary magnetic flux of each induction machine; A torque calculator for calculating the torque of each induction machine, torque difference detection means for inputting the torque of each induction machine and outputting a detection signal, and an operation logic for creating a control command from the operation command and the detection signal An induction machine control device, wherein a controller is newly added and the control command is input to the torque control means instead of the operation command.

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