The present invention provides a method and system for controlling the temperature of an electric motor by adjusting the electric losses in the motor. In an embodiment, the required load on the motor is determined and a first motor voltage is provided to meet the required load. A predetermined temperature set point for the motor is compared against the temperature of the motor and based on the temperature of the motor and the predetermined temperature set point, a secondary motor voltage is determined. The motor voltage may then be adjusted based on the calculated voltage and the motor load measurement adjusted based on the measured motor speed and actual motor voltage.

The present disclosure is constructed on the prior art inverter architecture, a pulse code width modulation (PCWM). This is an open loop motor control system without sensing its rotor position. The present disclosure employs a closed loop method to track the optimum efficiency motor operating point directly. A bench load test is conducted to gather information for an AI type control, which includes both load angle vs. voltage command charts and power factor vs. voltage command charts, with load levels as parameters for certain frequency command ranges. This way, the optimum efficiency motor operating points are generated a priori. The AI type control is mechanized to track the optimum efficiency motor operating points.

A motor drive apparatus that can continue operation within the upper limit of system control even if a voltage drop of an AC power source occurs during operation of a motor used for a hoist or a crane is provided. The inverter control unit of the motor drive apparatus includes a speed reference setting means for setting the rotation speed of the motor, means for detecting a speed deviation between the output of the rotation speed detection means for detecting the rotation speed of the motor and the output of the speed reference setting means, means for controlling the output current of the inverter according to the output of the speed deviation. The speed reference setting means includes a correction circuit for correcting an external speed command given from outside. The correction circuit corrects the external speed command according to a deviation between a detection value of a DC voltage and a first reference value when a voltage drop signal is received from the voltage drop detection means, and makes the corrected speed command as the output of the speed reference setting means.

An electric driven hydraulic fracking system is disclosed. A pump configuration that includes the single VFD, the single shaft electric motor, and the single hydraulic pump that is mounted on the single pump trailer. A power distribution trailer distributes the electric power generated by the power generation system at the power generation voltage level to the single VFD and converts the electric power at a power generation voltage level to a VFD voltage level and controls the operation of the single shaft electric motor and the single hydraulic pump. The power distribution trailer converts the electric power generated by the power generation system at the power generation level to an auxiliary voltage level that is less than the power generation voltage level. The power distribution trailer distributes the electric power at the auxiliary voltage level to the single VFD that controls an operation of the of the auxiliary systems.

An electric driven hydraulic fracking system is disclosed. A pump configuration that includes the single VFD, the single shaft electric motor, and the single hydraulic pump that is mounted on the single pump trailer. A power distribution trailer distributes the electric power generated by the power generation system at the power generation voltage level to the single VFD and converts the electric power at a power generation voltage level to a VFD voltage level and controls the operation of the single shaft electric motor and the single hydraulic pump. The power distribution trailer converts the electric power generated by the power generation system at the power generation level to an auxiliary voltage level that is less than the power generation voltage level. The power distribution trailer distributes the electric power at the auxiliary voltage level to the single VFD that controls an operation of the of the auxiliary systems.

An electric driven hydraulic fracking system is disclosed. A pump configuration includes the single VFD, the single shaft electric motor, and the single hydraulic pump mounted on the single pump trailer. A controller associated with the single VFD and is mounted on the single pump trailer. The controller monitors operation parameters associated with an operation of the electric driven hydraulic fracking system as each component of the electric driven hydraulic fracking system operates to determine whether the operation parameters deviate beyond a corresponding operation parameter threshold. Each of the operation parameters provides an indicator as to an operation status of a corresponding component of the electric driven hydraulic fracking system. The controller initiates corrected actions when each operation parameter deviates beyond the corresponding operation threshold. Initiating the corrected actions when each operation parameter deviates beyond the corresponding operation threshold maintains the operation of the electric driven hydraulic fracking system.

An electric driven hydraulic fracking system is disclosed. A pump configuration includes the single VFD, the single shaft electric motor, and the single hydraulic pump mounted on the single pump trailer. A controller associated with the single VFD and is mounted on the single pump trailer. The controller monitors operation parameters associated with an operation of the electric driven hydraulic fracking system as each component of the electric driven hydraulic fracking system operates to determine whether the operation parameters deviate beyond a corresponding operation parameter threshold. Each of the operation parameters provides an indicator as to an operation status of a corresponding component of the electric driven hydraulic fracking system. The controller initiates corrected actions when each operation parameter deviates beyond the corresponding operation threshold. Initiating the corrected actions when each operation parameter deviates beyond the corresponding operation threshold maintains the operation of the electric driven hydraulic fracking system.

A drive device drives a motor serving as a load. A first upstream switch is disposed upstream from the motor and a first downstream switch is disposed downstream from the motor in a first current path of current flowing via the motor. A second upstream switch is disposed upstream from the motor and a second downstream switch is disposed downstream from the motor in a second current path of current flowing via the motor. A direction of the current flowing in the motor when current flows in the first current path is different from a direction of the current flowing in the motor when current flows in the second current path. The first upstream drive circuit stops flow of current via the first upstream switch when the current flowing through the first upstream switch becomes greater than or equal to a current threshold.

A heater-integrated fuse is provided at a neutral point of a stator coil, and when a short-circuit failure of an inverter is detected, a fuse part of the heater-integrated fuse is cut by heating.

A hydraulic fracturing system includes a turbine generator for producing electricity at a well site, the turbine generator producing electrical energy at a voltage. The system also includes an electric pump electrically coupled to the turbine generator and receiving operative power from the turbine generator. The system further includes switch gear arranged between the electric pump and the turbine generator, the switch gear distributing electrical energy from the turbine generator to the electric pump, wherein the voltage remains substantially constant from the turbine generator to the electric pump.