CONTROL DEVICE FOR ELECTRIC ROTATING MACHINE

• US 20100262307A1
• Filed: 03/17/2010
• Published: 10/14/2010
• Est. Priority Date: 04/10/2009
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: IMURA, Akihiro
• Granted Patent: US 8,164,311 B2
• Time in Patent Office: Days
• US Class Current: 700/287
• 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 to be set in one of a plurality of controlled states and to apply a controlled voltage, corresponding to the controlled state of the power inverting circuit, to the electric rotating machine, comprising:

a first predicting unit that predicts the controlled variable of the electric rotating machine from information, indicating one controlled state set in the power inverting circuit, as a first prediction result, while using a second prediction result as an initial value of each first prediction result, for each of the controlled states set in the power inverting circuit;

a state determining unit that determines one controlled state from the first prediction results corresponding to the controlled states;

a control unit that controls the power inverting circuit to be set in the controlled state determined by the state determining unit; and

a second predicting unit that predicts the controlled variable of the electric rotating machine as the second prediction result from information, indicating the controlled state determined by the state determining unit before the prediction of the second prediction result.

2. The control device according to claim 1, wherein the control unit renews the controlled state of the power inverting circuit each time the state determining unit determines one controlled state, and the second predicting unit receives a physical quantity, from which the controlled variable is calculated, or the controlled variable, which appears in the electric rotating machine at a first renewal time at which the control unit sets the power inverting circuit in the controlled state determined before the first renewal time by the state determining unit, and predicts the controlled variable or the physical quantity, which appears in the electric rotating machine at a second renewal time, as the second prediction result from the received controlled variable or the received physical value and the information indicating the controlled state determined before the first renewal time by the state determining unit.

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 second predicting unit receives the controlled variable or the physical quantity every control period of time, and predicts the controlled variable or the physical quantity, which appears in the electric rotating machine at the second renewal time elapsed by one control period of time from the first renewal time, from the information indicating the controlled state set at the first renewal time by the control unit and the controlled variable or physical value appearing in the machine in response to the controlled state set at the first renewal time.

4. 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, the second predicting unit predicts the controlled variable or the physical quantity, which appears in the electric rotating machine at the second renewal time elapsed by one control period of time from the first renewal time, and the first predicting unit predicts the controlled variable or the physical quantity, which appears in the electric rotating machine at a third renewal time elapsed by one control period of time from the second renewal time, as one first prediction result from the information indicating one controlled state set at the second renewal time in the power inverting circuit, while using the controlled variable or the physical quantity predicted by the second predicting unit as the initial value of the controlled variable or the physical quantity to be predicted by the first predicting unit, for each of the controlled states.

5. The control device according to claim 4, wherein the control unit controls the power inverting circuit to be set in the controlled state determined by the state determining unit at the second renewal time.

6. The control device according to claim 1, wherein the controlled variable of the electric rotating machine is an electric current flowing through the electric rotating machine, a torque generated in the electric rotating machine, or a magnetic flux induced in the electric rotating machine.

7. The control device according to claim 1, wherein the power inverting circuit has a plurality of switching elements such that each switching element set in an on state electrically connects one of a plurality of voltage applying portions, applying different voltages, with one of terminals of the electric rotating machine while each switching element set in an off state electrically disconnects the corresponding voltage applying portion from the corresponding terminal of the electric rotating machine, each controlled state of the power inverting circuit corresponds to one of a plurality of patterns of the on and off states of the switching elements, and the control unit controls the switching elements to be set in the pattern corresponding to the controlled state determined by the state determining unit.

8. The control device according to claim 7, wherein the voltage applying portions are, respectively, a positive electrode and a negative electrode of a direct voltage source.

9. The control device according to claim 1, wherein the state determining unit calculates a difference between each first prediction result and an instructed value and determines the controlled state corresponding to the difference having a minimum value among values of the differences.