Resolver correction device and semiconductor device

Patent metadata

Field	Value
Publication number	US-10498266-B2
Application number	US-201715681852-A
Country	US
Kind code	B2
Filing date	Aug 21, 2017
Priority date	Aug 23, 2016
Publication date	Dec 3, 2019
Grant date	Dec 3, 2019

Abstract

To correct a frequency deviation generated in an input signal to an analog filter according to the rotation of a rotor in a resolver, a resolver correction device includes a phase shifter which shifts the phase of a first phase signal of the resolver, with respect to the signals at least having two phases and more, detected by the resolver. The phase-shifted first phase signal and a second phase signal are added, as a phase modulation signal with the excitation signal modulated by a rotation angle of the rotor in the resolver. A phase difference correction signal is generated based on a phase difference between the phase modulation signal of the resolver and the excitation signal. The adjusting amount of the phase shifter is calculated based on the phase difference correction signal, in which the phase shifter adjusts a phase shift amount according to the adjusting amount.

First claim

What is claimed is:

1. A resolver correction device comprising:
with respect to signals at least having two or more phases, including a first phase signal and a second phase signal, detected by a resolver excited by an excitation signal of a carrier frequency fc,
a phase shifter comprising a first operational amplifier, a capacitor, and a switch, wherein the phase shifter shifts a phase of the first phase signal of the resolver;
a first adder comprising a second operational amplifier, wherein the first adder adds the second phase signal and a third phase signal obtained by shifting the phase of the first phase signal, as a phase modulation signal with the excitation signal modulated by a rotation angle of a rotor in the resolver;
a frequency error correction unit comprising multiple multipliers and a second adder, wherein the frequency error correction unit generates a phase difference correction signal, based on a phase difference between the phase modulation signal of the resolver and the excitation signal; and
an adjuster comprising a register, a third adder, and a counter, wherein the adjuster calculates an adjusting amount of the phase shifter, based on the phase difference correction signal,
wherein the phase shifter adjusts a phase shift amount according to the adjusting amount.

2. The device according to claim 1 ,
wherein the adjuster calculates the adjusting amount of the phase shifter, based on the phase difference correction signal and a variation of the phase shift amount according to a temperature change in the phase shifter.

3. The device according to claim 2 , further comprising:
a phase shifter replica shifting a phase of the excitation signal of the resolver by the same phase shift amount as the phase shifter based on the adjusting amount; and
a phase difference detector which detects a phase difference between the excitation signal and the excitation signal phase-shifted by the phase shifter replica,
wherein the adjuster calculates the adjusting amount of the phase shifter, based on the phase difference detected by the phase difference detector and the phase difference correction signal.

4. The device according to claim 3 , further comprising:
the resolver including an excitation coil and a plurality of detection coils;
an excitation circuit which generates the excitation signal and applies the excitation signal to the excitation coil; and
a differential amplification circuit which differentially amplifies a phase signal detected by the pluralities of detection coils and outputs at least the first phase signal and the second phase signal,
wherein the phase shifter shifts the phase of the first phase signal, and
wherein the adder adds the phase-shifted first phase signal and the second phase signal, as the phase modulation signal with the excitation signal modulated by the rotation angle of the rotor in the resolver.

5. The device according to claim 2 , further comprising:
a temperature detecting circuit which measures a temperature of the resolver correction device, and
a register which calculates a variation of the phase shift amount of the phase shifter according to a temperature change, based on the temperature measured by the temperature detecting circuit,
wherein the adjuster calculates the adjusting amount of the phase shifter, based on the phase difference detected by the phase difference detector and the variation of the phase shift amount.

6. The device according to claim 1 , further comprising:
a counter which counts a phase difference between the excitation signal and the phase modulation signal;
a position calculator which calculates a rotation position of the rotor, based on a count value of the phase difference; and
a differentiation processing unit which differentiates a signal at the rotation position and calculates a rotation speed of the rotor,
wherein the frequency error correction unit generates a phase difference correction signal based on the rotation speed of the rotor.

7. A semiconductor device comprising:
with respect to signals at least having two or more phases, including a first phase signal and a second phase signal, detected by a resolver excited by an excitation signal of a carrier frequency fc,
a phase shifter circuit comprising a first operational amplifier, a capacitor, and a switch, wherein the phase shifter shifts a phase of the first phase signal of the resolver;
a first adding circuit comprising a second operational amplifier, wherein the first adding circuit adds the second phase signal and a third phase signal obtained by shifting the phase of the first phase signal, as a phase modulation signal with the excitation signal modulated by a rotation angle of a rotor in the resolver;
a frequency error correction circuit comprising multiple multipliers and a second adder circuit, wherein the frequency error correction circuit generates a phase difference correction signal, based on a phase difference between the phase modulation signal of the resolver and the excitation signal; and
an adjusting circuit comprising a register, a third adding circuit, and a counter, wherein the adjusting circuit calculates an adjusting amount of the phase shifter, based on the phase difference correction signal,
wherein the phase shifter circuit adjusts a phase shift amount according to the adjusting amount.

Assignees

• Renesas Electronics Corp

Inventors

• Ikenaga Yoshifumi

Classifications

• H02P6/16 Primary

  Circuit arrangements for detecting position · CPC title

• H02P6/153 Primary

  wherein the commutation is advanced from position signals phase in function of the speed · CPC title

• H02P6/185 Primary

  using inductance sensing, e.g. pulse excitation · CPC title