System and method of controlling an inverter based on a calculated capacitance of a DC link capacitor

摘要

A system, comprising a control regulation system, an inverter, a DC link capacitor, which is coupled to input connections of the inverter, at least one control apparatus, which is coupled to semiconductor switches of a half-bridge of the inverter, wherein the control apparatus is configured to actuate the semiconductor switch on the basis of a control signal from the control regulation system, at least one temperature sensor, which is configured to determine a change in temperature of the semiconductor switches in the half-bridge of the inverter, and a voltage sensor, which is configured to determine the voltage at the DC link capacitor is disclosed.

主权项

1. A system (100), comprising:
a control regulation system (50); an inverter (10); a DC link capacitor (2), which is coupled to input connections of the inverter (10); at least one control apparatus (4), which is coupled to semiconductor switches (1) of a half-bridge of the inverter (10), wherein the control apparatus (4) is configured to actuate the semiconductor switch (1) on the basis of a control signal (5) from the control regulation system (50); at least one temperature sensor (52), which is configured to determine a change in temperature of the semiconductor switches (1) in the half-bridge of the inverter (10); and a voltage sensor (51), which is configured to determine the voltage at the DC link capacitor (2), wherein the control regulation system (50) is configured to generate the control signal (5) as a series of control signal pulses, a pulse length of the control signal pulses having a duration that results in the semiconductor switches (1) in the half-bridge of the inverter (10) not becoming completely conductive during the control signal pulse, wherein the control regulation system (50) is configured to calculate a present capacitance of the DC link capacitor (2) on the basis of a determined change in temperature of the temperature sensor (52) between the beginning and the end of the control signal pulse and a determined change in voltage of the voltage sensor (51) between the beginning and the end of the control signal pulse, and wherein the operation of the system (100) is altered if the calculated capacitance of the DC link capacitor (2) indicates the DC link capacitor (2) is not functioning properly.