A power conversion apparatus includes: matrix converter circuitry configured to perform bidirectional power conversion between a primary side and a secondary side; and control circuitry configured to: calculate a deterioration level based on a secondary side current of the matrix converter circuitry, a carrier frequency, and a primary-secondary frequency difference between a primary side frequency and a secondary side frequency of the matrix converter circuitry; and output a deterioration notification in response to determining that the deterioration level exceeds a predetermined level.

A power conversion apparatus includes: matrix converter circuitry configured to perform bidirectional power conversion between a primary side and a secondary side; and control circuitry configured to: calculate a deterioration level based on a secondary side current of the matrix converter circuitry, a carrier frequency, and a primary-secondary frequency difference between a primary side frequency and a secondary side frequency of the matrix converter circuitry; and output a deterioration notification in response to determining that the deterioration level exceeds a predetermined level.

A power conversion apparatus includes: matrix converter circuitry configured to perform bidirectional power conversion between a primary side and a secondary side; and control circuitry configured to: calculate a deterioration level based on a secondary side current of the matrix converter circuitry, a carrier frequency, and a primary-secondary frequency difference between a primary side frequency and a secondary side frequency of the matrix converter circuitry; and output a deterioration notification in response to determining that the deterioration level exceeds a predetermined level.

A power conversion apparatus includes: matrix converter circuitry configured to perform bidirectional power conversion between a primary side and a secondary side; and control circuitry configured to: calculate a deterioration level based on a secondary side current of the matrix converter circuitry, a carrier frequency, and a primary-secondary frequency difference between a primary side frequency and a secondary side frequency of the matrix converter circuitry; and output a deterioration notification in response to determining that the deterioration level exceeds a predetermined level.

A power conversion apparatus includes: matrix converter circuitry configured to perform bidirectional power conversion between a primary side and a secondary side; and control circuitry configured to: select a first control mode in response to determining that a command-primary frequency difference between a command frequency and a primary side frequency of the matrix converter circuitry is above a predetermined threshold, wherein the first control mode includes causing a secondary side frequency of the matrix converter circuitry to follow the command frequency; select a second control mode in response to determining that the command-primary frequency difference is below the threshold, wherein the second control mode includes maintaining a primary-secondary phase difference between a secondary side phase and a primary side phase of the matrix converter circuitry within a predetermined target range; and control the matrix converter circuitry in accordance with a selection of the first control mode or the second control mode.

A power conversion system converts an input alternating-current voltage having a first frequency into an output alternating-current voltage having a second frequency lower than the first frequency. The power conversion system includes a voltage converter, a PDM controller, and a feedback controller. The voltage converter converts the input alternating-current voltage into the output alternating-current voltage in accordance with control signals and outputs the output alternating-current voltage to a load. The PDM controller performs pulse density modulation of an output voltage command value of the output alternating-current voltage to generate the control signals and outputs the control signals to the voltage converter. The feedback controller generates the output voltage command value based on an output current value of the voltage converter and a state of the load and outputs the output voltage command value to the PDM controller.

A power conversion system converts an input alternating-current voltage having a first frequency into an output alternating-current voltage having a second frequency lower than the first frequency. The power conversion system includes a voltage converter, a PDM controller, and a feedback controller. The voltage converter converts the input alternating-current voltage into the output alternating-current voltage in accordance with control signals and outputs the output alternating-current voltage to a load. The PDM controller performs pulse density modulation of an output voltage command value of the output alternating-current voltage to generate the control signals and outputs the control signals to the voltage converter. The feedback controller generates the output voltage command value based on an output current value of the voltage converter and a state of the load and outputs the output voltage command value to the PDM controller.

A power conversion apparatus includes: matrix converter circuitry to perform power conversion between a primary side electric power and a secondary side electric power; rectifier circuitry to convert the primary side electric power to charge a capacitor; and control circuitry to: set a changeover reference voltage at a first reference voltage when the primary side voltage magnitude is a first voltage magnitude and set the changeover reference voltage at a second reference voltage when the primary side voltage magnitude is a second voltage magnitude; and select, based on the changeover reference voltage and the terminal voltage, a connection state from: a first connection state in which the rectifier circuitry is connected to the capacitor by a first route including a current limit device; and a second connection state in which the rectifier circuitry is connected to the capacitor by a second route that bypasses the current limit device.

There is provided a method of generating a control strategy based on at least three switching states of a matrix converter. The at least three switching states are selected based on at least a predicted output current, associated with each switching state, and a desired output current. In particular, mathematical transformations of a desired output current as well as output currents associated with each of a plurality of switching states are used to identify appropriate switching states.

There is provided a method of generating a control strategy based on at least three switching states of a matrix converter. The at least three switching states are selected based on at least a predicted output current, associated with each switching state, and a desired output current. In particular, mathematical transformations of a desired output current as well as output currents associated with each of a plurality of switching states are used to identify appropriate switching states.