Control device for electric rotating machine

• US 8,164,311 B2
• Filed: 03/17/2010
• Issued: 04/24/2012
• Est. Priority Date: 04/10/2009
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Imura, Akihiro
• Primary Examiner(s): Cuevas, Pedro J
• Application Number:
  US12/725,702
• Publication Number:
  US 20100262307A1
• Time in Patent Office: 769 Days
• Field of Search: 322/37, 318/400.15, 375/240.12, 713/322
• US Class Current: 322/37
• CPC Class Codes: H02P 21/14 Estimation or adaptation of machine parameters, e.g. flux, current or voltage

Abstract

A control device has a unit for selecting each of states of an inverter applying a voltage to a generator, a unit for predicting a first current of the generator, flowing at a second time elapsed by one control period from a first time, from a detected current and the state of the inverter at the first time, a unit for predicting a second current of the generator at a third time elapsed by one control period from the second time while using the first current as an initial value of the second current, from information indicating one selected state set at the second time, for each selected state, a unit for determining one state corresponding to the second current nearest to instruction, and a unit for setting the inverter in the determined state at the second time to control current of the generator.

Claims

1. A control device which controls a controlled variable of an electric rotating machine by controlling a power inverting circuit, having a plurality of switching elements connecting and disconnecting a plurality of voltage applying portions applying different voltages with/from terminals of the electric rotating machine, to be set in one of voltage vectors determined according to on and off states of the switching elements, the controlled variable being at least one of an electric current flowing through the electric rotating machine, a torque of the electric rotating machine and a magnetic field of the electric rotating machine,

wherein the control device comprises:

a first predicting unit that, when a plurality of controlled states of the power inverting circuit corresponding to the voltage vectors are imaginarily set so as to set the power inverting circuit in each of the controlled states at a second renewal time, predicts the controlled variable of the electric rotating machine for each of the imaginarily-set controlled states;

a control unit that determines one controlled state of the power inverting circuit, expected at the second renewal time, from the controlled variable predicted by the first predicting unit and sets the power inverting circuit in the determined controlled state at the second renewal time; and

a second predicting unit that receives a present controlled state already determined by the control unit to be used for the power inverting circuit at a first renewal time preceding the second renewal time and predicts an initial value, to be used for the prediction performed by the first predicting unit, by using the present controlled state, and

wherein a value of the controlled variable predicted by the first predicting unit relates to a time after a time relating to the value predicted by the second predicting unit.

2. The control device according to claim 1, wherein the second predicting unit receives a detected value of either the controlled variable or a physical quantity, from which a value of the controlled variable can be calculated, and predicts a value of the controlled variable or the physical quantity, from which the value of the controlled variable can be calculated, expected at the second renewal time of the controlled state, set by the control unit, by using the detected value.

3. The control device according to claim 2, wherein the control unit renews the controlled state of the power inverting circuit every control period of time, and the first predicting unit predicts the controlled variable expected at a third renewal time, elapsed by one control period of time from the second renewal time of the controlled state set by the control unit, by using the value of the controlled variable predicted by the second predicting unit as the initial value.

4. The control device according to claim 3, wherein the second predicting unit predicts the value of the controlled variable or the physical quantity, from which the value of the controlled variable can be calculated, at the second renewal time, elapsed by one control period of time from the first renewal time, by using both the controlled state adopted at the first renewal time and either the value of the controlled variable or the physical quantity detected in synchronization with the first renewal time.

5. The control device according to claim 1, wherein the voltage applying portions are a positive terminal and a negative terminal of a direct current source, and the power inverting circuit has the switching elements which can connect each of the positive and negative terminals of the direct current source with any terminal of the electric rotating machine.