Abstract: A heat pump apparatus includes: a compressor including a motor; an inverter that applies a desired voltage to the motor; a current detector that detects current flowing to the motor; a drive-signal generation unit that generates a drive signal for the inverter; a magnetic-pole position estimation unit that changes a voltage phase of a voltage command value for a high-frequency voltage, and estimates a maximum-heat-amount acquisition magnetic-pole position when the generation unit applies the high-frequency voltage to the motor to heat the compressor; a steady heating control unit that determines an amplitude and voltage phase of the voltage command value from the maximum-heat-amount acquisition magnetic-pole position and a defined necessary amount of heat when the generation unit applies the high-frequency voltage to the motor to heat the compressor; and a control switching determination unit that causes one of the estimation unit and the heating control unit to operate.

Abstract: A DC power supply device includes a rectification circuit, a reactor, a first capacitor and a second capacitor, a first switching element to set the first capacitor in a charging state when the first switching element is in an off state and to set the first capacitor in a non-charging state when the first switching element is in an on state, a second switching element to set the second capacitor in the charging state when the second switching element is in the off state and to set the second capacitor in the non-charging state when the second switching element is in the on state, and a controller. The controller has a full-wave rectification mode as an operation mode in which one of the first and second switching elements is maintained in the off state and the other one of the first and second switching elements undergoes PWM control.

Abstract: A conveyance system includes a conveyance mechanism including two rollers, two drive devices, two measuring devices, and a controller. For a first period during which a sheet is conveyed with one of the two rollers, the controller calculates first and second control inputs U1 and U2 whereas for a second period during which the sheet is conveyed with the two rollers, the controller calculates the second control input U2, two estimated tension values R1 and R2, and the first control input U1=U2?UR. For an initial period of the second period, the controller adjusts the first control input U1 to restrain the first control input U1 from change.

Abstract: A conveyance system includes a conveyance mechanism including two rollers, two drive devices, two measuring devices, and a controller. For a first period during which a sheet is conveyed with one of the two rollers, the controller calculates first and second control inputs U1 and U2 whereas for a second period during which the sheet is conveyed with the two rollers, the controller calculates the second control input U2, two estimated tension values R1 and R2, and the first control input U1=U2?UR. For an initial period of the second period, the controller adjusts the first control input U1 to restrain the first control input U1 from change.

Abstract: There is provided a control system including: a motor, a moving apparatus, a detector, a driving circuit, and a controller. The controller executes: inputting, to the driving circuit, a first voltage command value up to a predetermined time; inputting, to the driving circuit, a second voltage command value since the predetermined time, and in accordance with a predetermined transfer function including an integral element; and setting an initial value of the integral element. The predetermined time is a time since the deceleration of the object has been started. When executing the switching from the first voltage command value to the second voltage command value, the controller sets a target position trajectory of the object up to the target stop position. Further, the controller sets the initial value of the integral element.

Abstract: There is provided a control system including: a motor, a moving apparatus, a detector, a driving circuit, and a controller. The controller executes: inputting, to the driving circuit, a first voltage command value up to a predetermined time; inputting, to the driving circuit, a second voltage command value since the predetermined time, and in accordance with a predetermined transfer function including an integral element; and setting an initial value of the integral element. The predetermined time is a time since the deceleration of the object has been started. When executing the switching from the first voltage command value to the second voltage command value, the controller sets a target position trajectory of the object up to the target stop position. Further, the controller sets the initial value of the integral element.

Abstract: A control system includes: a motor; a driving unit including a driving target and displacing the driving target in a first direction and a second direction opposite to the first direction by transmitting power from the motor to the driving target; a detection unit detecting a position of the driving target; and a controller controlling the motor. The controller is configured to execute: a displacement control process to displace the driving target in the first direction and the second direction; a determination process to determine a holding current value holding the driving target at a target stop position; and a holding control process to hold the driving target, which has been disposed at the target stop position in the displacement control process, at the target stop position based on the holding current value determined by the determination process.

Abstract: A control system includes: a motor; a driving unit including a driving target and displacing the driving target in a first direction and a second direction opposite to the first direction by transmitting power from the motor to the driving target; a detection unit detecting a position of the driving target; and a controller controlling the motor. The controller is configured to execute: a displacement control process to displace the driving target in the first direction and the second direction; a determination process to determine a holding current value holding the driving target at a target stop position; and a holding control process to hold the driving target, which has been disposed at the target stop position in the displacement control process, at the target stop position based on the holding current value determined by the determination process.

Abstract: A sheet transport apparatus includes: a first motor and a second motor; a first roller configured to: rotate upon receiving motive power from the first motor; and transport a sheet in a predetermined transport direction; a second roller which is provided on a downstream side of the first roller in the transport direction and which is configured to: rotate upon receiving motive power from the second motor while nipping the sheet transported by the first roller at a nip position; and transport the sheet further downstream in the transport direction; and a controller. The controller includes a motor control unit configured to perform a first process for rotating the first roller and a second process for rotating the second roller; and a first reaction-force estimating observer configured to calculate a first estimated value which is an estimated value of a reaction force acting on the first motor.

Abstract: A sheet transport apparatus includes: a first motor and a second motor; a first roller configured to: rotate upon receiving motive power from the first motor; and transport a sheet in a predetermined transport direction; a second roller which is provided on a downstream side of the first roller in the transport direction and which is configured to: rotate upon receiving motive power from the second motor while nipping the sheet transported by the first roller at a nip position; and transport the sheet further downstream in the transport direction; and a controller. The controller includes a motor control unit configured to perform a first process for rotating the first roller and a second process for rotating the second roller; and a first reaction-force estimating observer configured to calculate a first estimated value which is an estimated value of a reaction force acting on the first motor.