US 9,431,933 B2Granted

Inverter apparatus

AssigneeKabushiki Kaisha Toyota Jidoshokki

InventorsTomohiro Takami, Yoshiki Nagata

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Abstract

Provided is an inverter apparatus capable of preventing occurrence of overcurrent in an AC motor and stably controlling driving of the AC motor. The inverter apparatus controlling the AC motor included in an electric compressor includes a shunt resistor for detecting current flowing in the AC motor, and a limit value control unit controlling a current limit value for a detected current detected at the shunt resistor. The limit value control unit determines whether the number of times the detected current becomes equal to or more than the first threshold within a first predetermined time is equal to or more than a first number of times. The limit value control unit decreases the current limit value when the number of times the detected current becomes equal to or more than the first threshold within the first predetermined time is equal to or more than the first number of times.

Claims4

Dependent claims

An inverter apparatus for controlling an AC motor included in an electric compressor, comprising:

a current detection unit configured to detect current flowing in the AC motor;
and
a limit value control unit configured to control a current limit value for a detected current detected by the current detection unit,
the limit value control unit configured to:
compare the detected current and a first threshold, and count a number of times that the detected current becomes greater than or equal to the first threshold within a first predetermined time;
decrease the current limit value when the counted number of times that the detected current becomes greater than or equal to the first threshold within the first predetermined time is greater than or equal to a first number of times;
compare the detected current and a second threshold, and count a number of times that the detected current becomes greater than or equal to the second threshold within a second predetermined time longer than the first predetermined time;
and
increase the current limit value when the counted number of times that the detected current becomes greater than or equal to the second threshold within the second predetermined time is less than or equal to the a second number of times.

6 more elements

Dependencies are inferred from the claim text.

Facts

Application: 14/601,683Filed 21 Jan 2015
Priority: JP 2014-00966722 Jan 2014
Published: US 2015/0207438 A123 Jul 2015
Granted: 30 Aug 2016
Term ends: Not estimatedThe source records don’t support an estimate.

Classification7 codes

H02P 6/28
Arrangements for controlling synchronous motors or other dynamo-electric motors using electronic commutation dependent on the rotor position;…:…
H02P 29/032
Providing protection against overload without automatic interruption of supply: preventing damage to the motor, e.g. setting individual current…
H02P 6/06
Arrangements for controlling synchronous motors or other dynamo-electric motors using electronic commutation dependent on the rotor position;…:…
H02P 6/08
Arrangements for controlling synchronous motors or other dynamo-electric motors using electronic commutation dependent on the rotor position;…:…