Rotating electrical machine control device

A rotating electrical machine control device, which drives and controls a rotating electrical machine by performing switching control of a plurality of switching elements constituting an inverter that is connected to a DC power supply and is connected to the rotating electrical machine to convert power between DC and multiple-phase AC, and

• comprises at least asynchronous pulse-width modulation control and synchronous five-pulse control as control systems of the inverter,
• the asynchronous pulse-width modulation control being a control system in which the switching elements are controlled by a plurality of switching pulses output based on a carrier that is not synchronized with rotation of the rotating electrical machine,
• the synchronous five-pulse control being a control system in which the switching elements are controlled by the switching pulses output five times in one cycle of an electrical angle in synchronization with the rotation of the rotating electrical machine, and
• based on operation regions set by a relationship between torque and a rotational speed of the rotating electrical machine, the control system of the inverter being selected, wherein
• a five-pulse region, which is an operation region where the synchronous five-pulse control is selected, is set on a side where the rotational speed of the rotating electrical machine is higher and the torque is larger than in a PWM region, which is an operation region where the asynchronous pulse-width modulation control is selected,
• a region boundary between the five-pulse region and the PWM region has a first boundary and a second boundary,
• the second boundary is set on a side where the rotational speed of the rotating electrical machine is higher and the torque is larger than at the first boundary,
• when an operating point defined by the relationship between the torque and rotational speed of the rotating electrical machine changes from a state in which the asynchronous pulse-width modulation control is being executed, and crosses the second boundary, the control system is shifted from the asynchronous pulse-width modulation control to the synchronous five-pulse control,
• when the operating point changes from a state in which the synchronous five-pulse control is being executed, and crosses the first boundary, the control system is shifted from the synchronous five-pulse control to the asynchronous pulse-width modulation control,
• the second boundary is set such that the number of the switching pulses per unit rotational speed by the asynchronous pulse-width modulation control immediately before the operating point crosses the second boundary is smaller than the number of the switching pulses per the unit rotational speed by the synchronous five-pulse control immediately after the operating point crosses the second boundary, and
• the first boundary is set such that the number of the switching pulses per the unit rotational speed by the synchronous five-pulse control immediately before the operating point crosses the first boundary is smaller than the number of the switching pulses per the unit rotational speed by the asynchronous pulse-width modulation control immediately after the operating point crosses the first boundary.