Driving equipment for synchronous motors

Claim 2

A driving equipment for a synchronous motor, comprising: an inverter for converting a direct-current voltage to an alternating current or a direct current and supplying the current to said synchronous motor; a control apparatus for controlling the output voltage and frequency of said inverter; and a means for detecting or estimating the rotational speed of said synchronous motors; wherein said control apparatus is further equipped with a means for issuing a torque command that matches the rotational speed and a rotational speed command, and a means for receiving the torque command (T*) as an input signal, computing a current amplitude command (I*) and current phase command (φ*), and sending the commands as output signals; said receiving, computing and sending means performs the computation of the current amplitude command (I*), and current phase command (φ*) according to the following first and second linear functions using the torque command (T*) as a parameter; I*=A·T*+B φ*= F·T*+G; and A, B, F and G are constants determined for the synchronous motors to maximize achievable torque with a minimum current.

Claim 3

A driving equipment for a synchronous motor, according to claim 1 , wherein: said receiving, computing and sending means uses a third linear function for computing the current amplitude command (I*) which passes the origin of I-T coordinate in combination with the first linear function; said third linear function is defined by the expression I*=C·T* ; and C is a constant determined in connection with the concerned synchronous motor.

Claim 4

A driving equipment for a synchronous motor according to claim 1 , wherein; said receiving, computing and sending means uses a fourth linear function for computing the current phase command (φ*) which passes the origin of φ-T coordinate, in combination with the second linear function; said fourth linear function is defined by the expression, φ*= H·T*; and H is a constant determined in connection with the concerned synchronous motor.

Claim 5

A driving equipment for a synchronous reluctance motor, comprising: an inverter for converting a direct-current voltage to an alternating current or a direct current and supplying the current to said synchronous reluctance motors, in which a plurality of annular magnetic paths are formed by providing multilayer slits in a core of the motor rotor; a control apparatus for controlling the output voltage and frequency of said inverter; and means for detecting or estimating the rotational speed of said synchronous reluctance motor; wherein said control apparatus is further equipped with a means for issuing a torque command that matches the rotational speed and a rotational speed command, and a means for receiving the torque command (T*) as an input signal, computing a current amplitude command (I*) and a current phase command (φ*), and sending the commands as output signals; said receiving, computing and sending means performs the computation of the current amplitude command (I*) and current phase command (φ*) according to the following first (1) and second (2) linear functions is using the torque command (T*) as a parameter; I*=A·T*+B φ*= F·T*+G; and A, B, F and G are constants determined for the synchronous reluctance motor.

Claim 6

A driving equipment for a synchronous reluctance motor, comprising: an inverter for converting a direct-current voltage to an alternating current or a direct current and supplying the current to said synchronous reluctance motors, in which a plurality of annular magnetic paths are formed by providing multilayer slits in a core of the motor rotor; a control apparatus for controlling the output voltage and frequency of said inverter; and means for detecting or estimating the rotational speed of said synchronous reluctance motor; wherein said control apparatus is further equipped with a means for issuing a torque command that matches the rotational speed and a rotational speed command, and a means for receiving the torque command (T*) as an input signal, computing a current amplitude command (I*) and a current phase command (φ*), and sending the commands as output signals; said receiving, computing and sending means performs the computation of the current amplitude command (I*) and current phase command (φ*) according to the following first (1) and second (2) linear functions is using the torque command (T*) as a parameter; I*=A·T*+B φ*= F·T*+G; and A, B, F and G are constants determined for the synchronous reluctance motor.

Claim 7

A driving equipment for a synchronous reluctance motor according to claim 4 , wherein: said receiving, computing and sending means uses a third linear function for computing the current amplitude command (I*) which passes the origin of I-T coordinate in combination with the first linear function; said third linear function is defined by the expression I*=C·T*; and C is a constant determined for the synchronous reluctance motor.

Claim 8

A driving equipment for a synchronous reluctance motor according to claim 4 , wherein: said receiving, computing and sending means uses a fourth linear function for computing current phase command (φ*) which passes the origin of φ-T coordinate in combination with the second linear function; said fourth linear function is defined by the expression φ*= H·T*; and H is a constant determined in connection with the concerned synchronous reluctance motor.