Method for estimating a temperature of a transistor
AssigneeDeere & Company
InventorBrij N. Singh
Life of this patent
Estimating the term…
Abstract
A detector measures turn-off voltage change with respect to change in time between a collector and emitter of a transistor and peak voltage of the transistor at the collector. An electronic data processor determines intermediate parameters of turn-off current, the turn-on current and on-state voltage drop based on the turn-off voltage change and the peak voltage. The data processor determines the power or energy loss for one switching cycle of the transistor based on the turn-off current, the turn-on current and on-state voltage drop between the collector and emitter of the transistor. The data processor estimates an associated average die temperature for the transistor over the switching cycle.
Claims14
A method for estimating junction temperature or die temperature of a transistor, the method comprising:
- measuring turn-off change in voltage with respect to change in time between a collector and emitter of a transistor in a phase of an inverter;
- measuring peak voltage of the transistor between the collector and the emitter;
- determining intermediate parameters of turn-off current, the turn-on current and on-state voltage drop based on the turn-off voltage change and the peak voltage;
- determining the power or energy loss for one switching cycle of the transistor based on the turn-off current, the turn-on current and on-state voltage drop between the collector and emitter of the transistor;
- and
- estimating an associated average junction or die temperature for the transistor over the switching cycle based on the determined energy loss, observed inverter system temperature and thermal characteristic of an inverter system.
A method for estimating junction temperature or die temperature of a transistor, the method comprising:
- measuring turn-off change in voltage (dvce/dt) with respect to change in time between a collector and emitter of a transistor in a phase of an inverter;
- measuring peak voltage (vcepeak) of the transistor between the collector and the emitter;
- determining intermediate parameters of turn-off current (iceturnoff), the turn-on current (iceturnon) and on-state voltage drop (vceon) based on the turn-off voltage change (dvce/dt) and the peak voltage (Vcepeak);
- determining the power or energy loss for one switching cycle of the transistor based on the turn-off current (iceturnoff);
- the turn-on current (iceturnon) and on-state voltage drop (vceon) between the collector and emitter of the transistor;
- and
- estimating an associated average junction or die temperature for the transistor over the switching cycle based on the determined energy loss, observed inverter system temperature and thermal characteristic of an inverter system.
Dependencies are inferred from the claim text.