Malfunction detecting device and malfunction detecting method for cooling device
AssigneeToyota Jidosha Kabushiki Kaisha
InventorOsamu Kitazawa
Life of this patent
Estimating the term…
Abstract
An ECU executes a program including the steps of: obtaining a first temperature Ta of a first semiconductor element; obtaining a second temperature Tb of a third semiconductor element; determining that it is in a normal state in which clogging has not occurred, when a rotating speed Nm2 of a second MG is more than a threshold value Nm2 and the magnitude of a difference between the first temperature Ta and the second temperature Tb is less than a threshold value ΔT; and determining that the clogging of a foreign matter has occurred in a predetermined site when the magnitude of the difference between the first temperature Ta and the second temperature Tb is equal to or more than the threshold value ΔT.
Claims5
A malfunction detecting device for a cooling device for cooling an electric device provided in a vehicle and including a first semiconductor element and a second semiconductor element, substantially a same magnitude of currents flowing in said first semiconductor element and said second semiconductor element, the cooling device including a first heat dissipating portion for dissipating heat of said first semiconductor element, a second heat dissipating portion for dissipating heat of said second semiconductor element, and a coolant passage for allowing coolant to flow in said first heat dissipating portion and said second heat dissipating portion in parallel, said coolant passage being provided with a predetermined site which is formed in advance and in which clogging of a foreign matter is likely to occur on a path via which said coolant flows into said first heat dissipating portion,
- the malfunction detecting device comprising:
- a first temperature detecting unit for detecting a first temperature of said first semiconductor element;
- and
- a control unit for detecting occurrence of said clogging in said predetermined site when a magnitude of a difference between said first temperature and a second temperature of said second semiconductor element exceeds a permissible value.
A malfunction detecting method for a cooling device for cooling an electric device provided in a vehicle and including a first semiconductor element and a second semiconductor element, substantially a same magnitude of currents flowing in said first semiconductor element and said second semiconductor element, the cooling device including a first heat dissipating portion for dissipating heat of said first semiconductor element, a second heat dissipating portion for dissipating heat of said second semiconductor element, and a coolant passage for allowing coolant to flow in said first heat dissipating portion and said second heat dissipating portion in parallel, said coolant passage being provided with a predetermined site which is formed in advance and in which clogging of a foreign matter is likely to occur on a path via which said coolant flows into said first heat dissipating portion,
- the malfunction detecting method comprising the steps of:
- detecting a first temperature of said first semiconductor element;
- and
- detecting occurrence of said clogging in said predetermined site when a magnitude of a difference between said first temperature and a second temperature of said second semiconductor element exceeds a permissible value.
Dependencies are inferred from the claim text.