Denso Corporation

Takahumi Oowada

Ryuji Omata

Taizo Kondo

Yasuhiro Nakai

Hiroya Tsuji

Hiroshi Inamura

Tatsuru Morioka

A switching control apparatus is applied to a load drive system that includes a DC voltage converter having a reactor and at least one switching element, and a power transducer including multiple switching element pairs. The switching control apparatus controls a switching timing of the switching element in the DC voltage converter and the switching element pairs in the power transducer. The switching control apparatus includes a DC voltage converter control circuit, a DC voltage converter drive circuit, a power transducer control circuit, a power transducer drive circuit, a switching prohibition period calculation portion, and a switching correction portion.

Switching control apparatus of load drive system

In a position detection device, an amplitude modulation is executed for AC excitation signals Sc using modulation wave signals. Differential amplifiers execute a voltage conversion of the modulated wave signal Sin, Cos to digital data SIN, COS and transmit them to a microcomputer. The microcomputer multiplies the modulated wave signals SIN, COS with parameters cos &#x3c6;, sin &#x3c6;, and executes a subtraction of the multiplied value to obtain an error-correlation value &#x3b5;. An angle calculations section in the microcomputer receives a detected value &#x3b5;c obtained by multiplying the error-correlation value &#x3b5; with a binary detection signal Rd. The binary detection signal Rd corresponds to a positive sign or a negative sign of the signal Sc. It is adjusted that the sampling number of samples of the signal Rd corresponding to a positive value is equal to that corresponding to a negative value during one period of the signal Sc.

Position detection device

A control apparatus controls an AC motor by detecting current passing through one phase. The apparatus includes an upper controller which includes a torque command calculation section, and a torque monitoring section monitoring torque to determine whether the torque is within a range, and a lower controller which controls current supply to an inverter based on a torque command value to control the motor, and which acquires information on a current-supply state and a rotation state of the motor and transmits information on a control state to the upper controller. At least one of the controllers estimates a current estimate value of an estimated phase or a d-q axis current estimate value based on a current detection value of the one phase and an electrical angle, and calculates information for monitoring torque based on the current estimate value. The torque monitoring section monitors the torque based on the information.

Control apparatus for AC motor

A switching control device is applied to a motor generator drive system equipped with a boost converter and an inverter. In order to avoid generation of a superimposed surge voltage, the switching control device corrects a switching timing tsw of the booster converter so that a switching timing of the booster converter is not overlapped with a switching timing of the inverter. A booster converter switching correction means corrects the switching timing tsw of the correction target to bring forward and before a start timing tpa of the switching inhibition period Pp. This makes it possible to suppress fluctuation in output of a load due to deterioration in controllability of the electric power converter, for example, suppress fluctuation in output torque of a motor generator.

Switching control device

A control device of a three-phase AC motor includes: an inverter that drives the AC motor; a current sensor that senses a current flowing in a sensor phase of the AC motor as a sensor phase current; and a controller that switches on and off a switching element of the inverter to control a current flowing through the AC motor. The controller includes: a current estimation device that estimates d-axis and q-axis current estimated values based on the sensor phase current and an electric angle of the AC motor; and a zero-crossing interpolation device that interpolates a command value relating to a voltage of the AC motor when the sensor phase current is in a zero cross range, which includes a zero point. When the sensor phase current is in the zero cross range, the zero-crossing interpolation device interpolates the command value with a continuous variable value.

Control device of AC motor

In a position detection device, an amplitude modulation is executed for AC excitation signals Sc using modulation wave signals. Differential amplifiers execute a voltage conversion of the modulated wave signal Sin, Cos to digital data SIN, COS and transmit them to a microcomputer. The microcomputer multiplies the modulated wave signals SIN, COS with parameters cos &#x3c6;, sin &#x3c6;, and executes a subtraction of the multiplied value to obtain an error-correlation value &#x3b5;. An angle calculations section in the microcomputer receives a detected value &#x3b5;c obtained by multiplying the error-correlation value &#x3b5; with a binary detection signal Rd. The binary detection signal Rd corresponds to a positive sign or a negative sign of the signal Sc. The sampling time of the AC excitation signal Sc is set to a time at which an absolute value of the AC excitation signal Sc exceeds a regulated value.

A control device of a three-phase AC motor includes: an inverter for driving the motor; a current sensor for sensing a sensor phase current of the motor; and a controller for controlling the motor. The controller includes: a current estimation device for estimating d-axis and q-axis current estimated values based on the sensor phase current and an electric angle of the motor; and a zero-crossing interpolation device for interpolating the d-axis and q-axis current estimated values by fixing the d-axis and q-axis current estimated values when the sensor phase current is in a zero cross range, which includes a zero point, so that the sensor phase current crosses the zero point, and for outputting interpolated d-axis and q-axis current estimated values as fixed d-axis and q-axis values, which are used for a feedback control relating to current flowing through the motor.

In an apparatus, a controller performs, as a calculation of d- and q-axis values of a current vector, a first task and a second task. The first task expands one of a measured first phase current and another phase current into Fourier series of the corresponding phase current as a function of an electric rotational angle of an AC motor. The first task extracts a first-order component from the Fourier series to obtain first and second Fourier coefficients of the first-order component. The second task calculates the d-axis value as a first sum of the first and second Fourier coefficients to which temporally-invariant constants of a first pair have been multiplied, and the q-axis value as a second sum of the first and second Fourier coefficients to which temporally-invariant constants of a second pair have been multiplied.

Apparatus for controlling AC motor

According to a control apparatus for an AC motor, a switching section selects a two-phase control current value as a current fixing value, when a first current detection value of a first phase of the AC motor and a second current detection value of a second phase of the AC motor are normal. The switching section selects an one-phase control current value, which is calculated based on a normal phase current detection value, which is a value of a normal phase and is one of the first and second current detection values, as the current fixing value, when an abnormality is detected in part of the first and second current detection values, and a predetermined period has elapsed from the detection of the abnormality.

According to a control apparatus for an AC motor, a switching section selects a two-phase control current value as a current fixing value, when a first current detection value of a first phase of the AC motor and a second current detection value of a second phase of the AC motor are normal. The switching section selects an one-phase control current value, which is calculated based on a normal phase current detection value, which is a value of the normal phase and is one of the first and the second current detection values, as the current fixing value, when it is determined that the current supplied to the AC motor has been stabilized after an abnormality is detected in part of the first and second detection values.

A control device of a three-phase AC motor includes: an inverter; a current sensor for a sensor phase current; and a controller switching a switching element of each phase of the inverter and having a current estimation device, which calculates a sensor-phase-standard current phase according to &#x3b1; and &#x3b2; axis currents and a current estimated value of another phase. The current estimation device calculates the &#x3b1; axis current at every switching and intermediate timings, calculates a first differential value of the &#x3b1; axis current at every switch timing, calculates the &#x3b2; axis current according to the first differential value, calculates a second differential value of the &#x3b1; axis current at every intermediate timing, and calculates the &#x3b2; axis current according to the second differential value. The intermediate timing is set to have an unequal interval between two adjacent switch timings.

The abnormality determination apparatus, which is for determining presence of an abnormality in an angle detection device configured to output an output signal having a value equivalent to a rotational angle of a rotating body, includes a smoothing device configured to receive the output signal of the angle detection device to smooth a dependent variable of a function whose independent variable is the rotational angle equivalent value, and a parameter calculation device for calculating an abnormality determination parameter based on the dependent variable smoothed by the smoothing device. The function is such that an integrated value of the rotational angle equivalent value over a predetermined time section is always positive or negative, and is configured to vary the dependent variable continuously in accordance with continuous variation of the independent variable in at least a part of the predetermined time section.

Abnormality determination apparatus for angle detection device

A control apparatus for use with an electric power conversion system which is equipped with a dc/ac converter connected to an electric rotating machine and a capacitor joined to input terminals of the dc/ac converter. The control apparatus stores an angle of rotation (i.e., start angle &#x3b8;) of the electric rotating machine before start of control of energization of the electric rotating machine to discharge the capacitor and determines command currents idr and iqr which will result in zero (0) torque in the electric rotating machine. The control apparatus includes a command current correcting circuit which corrects the command currents idr and iqr by a difference between a current angle &#x3b8; of rotation of the electric rotating machine and the start angle &#x3b8;, thereby avoiding constant rotation of the electric rotating machine when the capacitor is discharged.

Control apparatus for electric rotating machine

In an abnormality diagnosing system for first and second current sensors for measuring a current, an obtaining unit obtains at least one pair of measured values of the first and second current sensors. The at least one pair of measured values is measured by the first and second current sensors at a substantially same timing. A diagnosing unit diagnoses whether there is an abnormality in at least one of the first and second current sensors based on a function defining a relationship between the at least one pair of measured values of the first and second current sensors.

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Kariya, Japan

Takahumi Oowada