The present disclosure includes techniques for implementing a variable speed drive (VSD) in an environmental conditioning system to facilitate mitigating or eliminating system faults. The variable speed drive drives a motor during on-cycles and heats motor windings of the motor during off-cycles. The variable speed motor drive includes a rectifier that converts alternative-current (AC) power input to a direct-current (DC) power output, a DC bus that is coupled to the rectifier and includes a DC bus transistor, and an inverter. The DC bus transistor pre-charges a DC capacitor of the DC bus to drive the motor during on-cycles and receives a gate pulse with a duty cycle based on a differential temperature, where the gate pulse heats the motor windings. The inverter receives the gate pulse applied to the DC bus transistor and transmits it a motor winding to prevent moisture on the motor winding.

The present disclosure includes techniques for implementing a variable speed drive (VSD) in an environmental conditioning system to facilitate mitigating or eliminating system faults. The variable speed drive drives a motor during on-cycles and heats motor windings of the motor during off-cycles. The variable speed motor drive includes a rectifier that converts alternative-current (AC) power input to a direct-current (DC) power output, a DC bus that is coupled to the rectifier and includes a DC bus transistor, and an inverter. The DC bus transistor pre-charges a DC capacitor of the DC bus to drive the motor during on-cycles and receives a gate pulse with a duty cycle based on a differential temperature, where the gate pulse heats the motor windings. The inverter receives the gate pulse applied to the DC bus transistor and transmits it a motor winding to prevent moisture on the motor winding.

A fan heater (1) has a motor (M) with motor windings (W) and a rotor that is connected to a fan (V) for delivering ambient air at least partially along the motor windings (W). At least one motor winding is configured as a heater winding (HW) for generating a specific heat output or amount of heat as intended.

A control device that controls cooling of a rotating electrical machine for driving a vehicle includes an arithmetic operation unit that executes predetermined arithmetic operation processing, and a storage unit that is accessible by the arithmetic operation unit. First temperature information from a first temperature detection unit that detects a temperature of a first refrigerant that exchanges heat with at the rotating electrical machine, second temperature information from a second temperature detection unit that detects a temperature of a second refrigerant that exchanges heat with a winding of the rotating electrical machine and is cooled by the first refrigerant, third temperature information from a rotating electrical machine temperature detection unit detects a temperature of the rotating electrical machine, and fourth temperature information from an outside air temperature detection unit are input. The second temperature information is verified by using the first, second, third, and fourth temperature information.

A processing apparatus acquires a first rise transition that is a rise transition of the temperature of a winding and a second rise transition that is a rise transition of the temperature detected by a temperature sensor in a state where voltage application for raising the temperature of the winding to a predetermined temperature is performed, determines a predetermined temperature characteristic model by calculating a predetermined parameter on the basis of the second rise transition, and further determines a winding temperature characteristic model by calculating a winding related parameter on the basis of the first rise transition.

A processing apparatus acquires a first rise transition that is a rise transition of the temperature of a winding and a second rise transition that is a rise transition of the temperature detected by a temperature sensor in a state where voltage application for raising the temperature of the winding to a predetermined temperature is performed, determines a predetermined temperature characteristic model by calculating a predetermined parameter on the basis of the second rise transition, and further determines a winding temperature characteristic model by calculating a winding related parameter on the basis of the first rise transition.

A detection system and method for rotor dynamic turn-to-turn short circuit fault of synchronous generator are disclosed. The system includes a motor, a synchronous generator, a current transformer, an acquisition card, an infrared temperature sensor, a temperature acquisition instrument and a control terminal. The rotor winding dynamic turn-to-turn short circuit fault of synchronous generator is detected and located by measuring the double judgment standards of the temperature signal of rotor winding and the three-phase current signal of stator winding. The method is easy to operate and has high sensitivity. The detection and location process of the fault is efficient and reliable. The dynamic turn-to-turn short circuit fault can be detected in the early stage of the formation of rotor static turn-to-turn short circuit, so as to reduce the loss of power plant fault shutdown and better meet the needs of practical application.

An electric tool includes a motor, an operation part provided to be operable by a user, a motor drive control unit configured to perform control of driving the motor in response to the operation part being operated, a temperature sensor, and a temperature determination unit configured to determine overheating of the motor. The temperature determination unit is configured to estimate a temperature of the motor based on a drive situation of the motor and a detection result of the temperature sensor, and to determine the overheating of the motor based on the estimated temperature.

An electric tool includes a motor, an operation part provided to be operable by a user, a motor drive control unit configured to perform control of driving the motor in response to the operation part being operated, a temperature sensor, and a temperature determination unit configured to determine overheating of the motor. The temperature determination unit is configured to estimate a temperature of the motor based on a drive situation of the motor and a detection result of the temperature sensor, and to determine the overheating of the motor based on the estimated temperature.

A temperature estimation device estimates a drive duty ratio by taking account of the influence of ambient temperature on the energization to a coil part, on the basis of a drive duty ratio and the ambient temperature, and estimates the power consumption of a motor when the coil part is energized with the estimated drive duty ratio, the power consumption of the motor, this power consumption being accompanied by the heat dissipation of the coil part, the power difference between both the power consumption values, the temperature time constant of the coil part, and a temperature variation during a period of the temperature time constant of the coil part, and estimates the temperature variation of the coil part from the ambient temperature on the basis of these estimated values and a last temperature variation of the coil part.