An inverter control device that controls a multiple of inverters configured to use the same positive and negative direct current voltage bus lines connected to a power supply and driving a corresponding multiple of motors, the inverter control device including smoothing control means that controls an inverter outflow current so that voltage of the power supply is smoothed by a smoothing capacitor connected to the positive and negative direct current voltage bus lines, and two-phase modulation operation means that fixes a predetermined one phase of a three-phase modulated wave at either a maximum voltage or minimum voltage the inverter can output determined by a voltage between the positive and negative direct current voltage bus lines, and calculates a modulated wave that causes the other two phases to switch.

A backpack-type blower according to one aspect of the present disclosure includes a plurality of fans, a plurality of DC power supplies and a backpack. The plurality of fans and the plurality of DC power supplies are mounted on the backpack. The backpack-type blower is configured to blow winds from the plurality of fans together.

A driving system for electric vehicles. The driving system may have two or more electric motors, each with voltage inputs, which are connected to the axles and tires of the vehicle. A variable input control may provide a signal that indicates its current operation position to a vehicle control unit. The vehicle control unit receives the information from the variable input control and determines how much power to send to each of the electric motors' voltage inputs.

A power tool is provided including a brushless electric motor, a switching arrangement having motor switches and interposed between the electric motor and a power supply, and a controller configured to control a switching operation of the motor switches for driving the electric motor and enforce a current limit on the current delivered to the electric motor. The controller receives a measure of current passing from the power supply to the switching arrangement and takes corrective action to reduce current delivered to the electric motor if the measured current exceeds the current limit. The controller further receives a temperature signal indicative of temperature of the power tool and adjusts the current limit in accordance with the temperature signal. Additional or alternatively, the controller adjusts the current limit at tool start-up.

A power tool is provided including a brushless electric motor, a switching arrangement having motor switches and interposed between the electric motor and a power supply, and a controller configured to control a switching operation of the motor switches for driving the electric motor and enforce a current limit on the current delivered to the electric motor. The controller receives a measure of current passing from the power supply to the switching arrangement and takes corrective action to reduce current delivered to the electric motor if the measured current exceeds the current limit. The controller further receives a signal corresponding to at least one of a type and/or a nominal voltage of the power supply and sets the current limit based on the received signal.

A power tool is provided including a brushless electric motor, a switching arrangement having motor switches and interposed between the electric motor and a power supply, and a controller configured to control a switching operation of the motor switches for driving the electric motor and enforce a current limit on the current delivered to the electric motor. The controller receives a measure of current passing from the power supply to the switching arrangement and takes corrective action to reduce current delivered to the electric motor if the measured current exceeds the current limit. The controller is further configured to initiate a protective response if a number of time intervals in which the measured current exceeds the current limit exceeds a predetermined threshold.

A driving system for electric vehicles. The driving system may have two or more electric motors, each with voltage inputs, which are connected to the axles and tires of the vehicle. A variable input control may provide a signal that indicates its current operation position to a vehicle control unit. The vehicle control unit takes the information from the variable input control and determines how much power to send to each of the electric motors' voltage inputs.

The invention relates to a control system (1) comprising a multi-motor inverter (PWR) for the controlled parallel operation of a number of n EC motors (M1, . . . , Mn) whose respective rotor position is detected sensorlessly and controlled by the common inverter.

A driver includes: a first motor located so as to rotate a driving shaft; a second motor located so as to rotate the driving shaft; and circuitry. The circuitry performs control while switching between a dual mode and a single mode. In the dual mode, the circuitry drives the first motor and the second motor together. In the single mode, the circuitry drives a drive target motor that is one of the first motor and the second motor and performs such control as to set one or more among a rotational speed, rotation acceleration, and rotation deceleration of the drive target motor to be lower than that or those in the dual mode.

A moving-magnet type linear motor controlling system which can highly accurately control carts even when a plurality of coil units apply forces to the carts is provided. The moving-magnet type linear motor controlling system has: a plurality of coil units having a plurality of coils; a position detecting unit for detecting the positions of the plural carts which are moved along the plurality of coil units; and a controlling unit for determining a ratio of currents which are supplied to the plural coil units on the basis of the positions of the plural carts and an impedance and thrust characteristics of each of the plural coil units.