Method and detector device for monitoring current sensors, and electric drive system
AssigneeRobert Bosch GmbH
InventorSebastian Paulus
Life of this patent
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Abstract
The invention relates to current sensor diagnostics in an electric drive system. According to the invention, a net current is formed from the sensor values provided by the current sensors. If this net current deviates significantly from zero, a complex current sum can be calculated using the rotor angle of the electric machine. This complex current sum is based on the current RMS current in the electric drive system in order to indicate deviations in the current gain factors of the current sensors used.
Claims8
A method for monitoring current sensors (21-23) for phase currents in a multiphase electrical drive system, the method comprising the steps of:
- detecting (S1) the sensor values for the phase currents, in each case one current sensor (21-23) determining a phase current of the multiphase electric drive system and providing a sensor value corresponding to the determined phase current;
- calculating (S2) a current sum using the detected sensor values from the current sensors (21-23);
- determining (S3) a real portion and an imaginary portion of a complex current sum using a rotor angle of the electric machine (2) in the electric drive system;
- calculating (S4) a complex gain error from a quotient of the real portion of the complex current sum and a current effective phase current amplitude and a quotient of the imaginary portion of the complex current sum and the current effective phase current amplitude;
- and
- calculating (S5) a magnitude of the complex gain error.
A detector device (10) for monitoring current sensors for phase currents in a multiphase electrical drive system, the detector comprising:
- an input interface (11) which is configured to detect sensor values for phase currents, in each case a current sensor (21-23) determining a phase current of the multiphase electrical drive system and providing a sensor value corresponding to the determined phase current;
- a computing unit (12) configured to calculate a current sum using the detected sensor values from the current sensors (21-23), to determine a real portion and an imaginary portion of a complex current sum using a rotor angle of the electric machine (2) in the electric drive system, to calculate a complex gain error from a quotient of the real portion of the complex current sum and a current effective phase current amplitude and a quotient of the imaginary portion of the complex current sum and the current effective phase current amplitude, and to calculate a magnitude of the complex gain error.
Dependencies are inferred from the claim text.