Motor control system
First Claim
1. A motor control system comprising:
- a switch circuit for supplying a driving current to a motor;
a current sensing circuit for detecting the driving current and converting the detected current to a voltage; and
an amplification circuit for amplifying the voltage converted by said current sensing circuit, wherein said motor control system further comprises means for compensating an input offset of said amplification circuit.
1 Assignment
0 Petitions
Accused Products
Abstract
A motor control system which can realize current detection with high accuracy by using an amplifier having an ordinary level of accuracy and can avoid deterioration of current detection accuracy even when emperature is changed. The motor control system comprises a switch circuit for supplying a driving current to a motor, a resistor for detecting the driving current, an amplification circuit for amplifying a potential difference across the resistor, an input section switch unit disposed in an input section of the amplification circuit and changing over the potential difference to be forward biased or reverse biased, an output section switch unit disposed in an output section of the amplification circuit and changing over an output voltage of the amplification circuit to be forward biased or reverse biased, and a CPU for averaging a voltage produced when the output voltage of the amplification circuit is forward biased, and a voltage produced when the output voltage of the amplification circuit is reverse biased.
52 Citations
17 Claims
-
1. A motor control system comprising:
-
a switch circuit for supplying a driving current to a motor;
a current sensing circuit for detecting the driving current and converting the detected current to a voltage; and
an amplification circuit for amplifying the voltage converted by said current sensing circuit, wherein said motor control system further comprises means for compensating an input offset of said amplification circuit. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
-
-
13. A motor control system comprising:
-
a switch circuit including a high-side switch and a low-side switch and supplying a driving current to a three-phase motor;
a resistor for detecting the driving current;
an amplification circuit for amplifying a potential difference across said resistor;
input section switch means disposed in an input section of said amplification circuit and changing over the potential difference to be forward biased or reverse biased;
output section switch means disposed in an output section of said amplification circuit and changing over an output voltage of said amplification circuit to be forward biased or reverse biased; and
a processing unit for averaging a first output voltage produced when the output voltage of said amplification circuit is forward biased, and a second output voltage produced when the output voltage of said amplification circuit is reverse biased. - View Dependent Claims (14, 15, 16, 17)
-
Specification