Disclosed are a variable capacity compressor operation mode determination method and device, a variable capacity compressor and an air conditioner. The variable capacity compressor operation mode determination method includes: detecting a current value of a compressor at present as A1 before switching an operation mode of the compressor; detecting the current value of the compressor at present as A2 after switching the operation mode of the compressor and reaching a preset time; comparing A1 and A2, determining that the switching of the operation mode of the compressor is successful when a ratio relationship between A1 and A2 satisfies a preset condition, and determining that switching of the operation mode of the compressor is failed when the ratio relationship between A1 and A2 dissatisfies a preset condition.

A method for controlling a permanent magnet (PM) synchronous motor in an ESP application is provided. A load angle of the PM motor is estimated. A voltage adjustment value is determined for the PM motor based at least on the estimated load angle of the PM motor. A voltage to be applied to the PM motor is determined based on the voltage adjustment value.

The disclosure discloses a method and a device for controlling cylinder switching of a compressor, a unit and an air conditioning system. The method includes: determining whether the compressor needs to perform cylinder switching; if so, adjusting current operating frequency according to a system pressure difference so that both the adjusted operating frequency and the system pressure difference meet a cylinder switching condition of the compressor; and controlling the compressor to perform cylinder switching. At the moment, the system pressure difference and the operation frequency are stable, and would not interfere the compressor's maintaining of the single-cylinder or double-cylinder operation state, which guarantees the energy efficiency of the unit where the compressor is located, and improves the use experience of a user.

An electric compressor includes an electric motor, and a motor controller configured to drive the electric motor. The motor controller includes a high voltage circuit board on which switching elements are mounted, a low voltage circuit board on which a control circuit controlling switching operation of the switching elements is mounted, an input connector, an output connector, and a current sensor. The high voltage circuit board and the low voltage circuit board are stacked with each other. The output connector is integrated with a detection busbar that provides electrical connection between the high voltage circuit board and the low voltage circuit board, and through which detection signals indicative of the output current are output to the control circuit.

An in-vehicle motor-driven compressor includes a temperature rise estimator configured to estimate a temperature rise of the diode based on an expected reverse current, an on-voltage of the diode, and a heat resistance of the diode. The in-vehicle motor-driven compressor further includes a rotation speed controller configured to set a rotation speed limit of the electric motor, based on the estimated temperature rise of the diode so that a temperature of the diode does not exceed a junction temperature of the diode even when the electric motor is stopped and the reverse current flows through the diode, and limit a rotation speed of the electric motor to lower than or equal to the rotation speed limit.

An electrically operated device (10) includes an electric motor (36) with an electrical cord set (30). The cord set (30) includes an electrical connecting plug (80) for coupling with an AC electrical outlet. The device (10) further includes a detector (46). A control (42) is electrically coupled to the motor (36) and electrically coupled to the detector (46) for controlling the level of electric current drawn by the electric motor (36) from the AC electrical outlet. The detector (46) detects whether the electrical connecting plug (80) is connected to a 15 Amp electric receptacle or to a 20 Amp electric receptacle and, in response, the control (42) establishes the electric profile of the electric motor (36) to correspond to the 15 Amp electric receptacle or to the 20 Amp electric receptacle.

The disclosure discloses a method and a device for controlling cylinder switching of a compressor, a unit and an air conditioning system. The method includes: determining whether the compressor needs to perform cylinder switching; if so, adjusting current operating frequency according to a system pressure difference so that both the adjusted operating frequency and the system pressure difference meet a cylinder switching condition of the compressor; and controlling the compressor to perform cylinder switching. At the moment, the system pressure difference and the operation frequency are stable, and would not interfere the compressor's maintaining of the single-cylinder or double-cylinder operation state, which guarantees the energy efficiency of the unit where the compressor is located, and improves the use experience of a user.

The invention relates to a method for controlling a start-up of an electric vacuum pump for a vacuum system of a vehicle, wherein the start-up can occur according to at least two different start-up modes, i.e., according to a standard mode and according to at least one special mode, wherein in the standard mode the vacuum pump is connected to a supply voltage in a non-clocked manner and in the special mode the vacuum pump is connected to a supply voltage in a dynamically clocked manner.

A method for controlling a permanent magnet (PM) synchronous motor in an ESP application is provided. A load angle of the PM motor is estimated. A voltage adjustment value is determined for the PM motor based at least on the estimated load angle of the PM motor. A voltage to be applied to the PM motor is determined based on the voltage adjustment value.

A method is for surveillance of an operating state of a pumping device connected to a process chamber in order to determine a failing operating state of the pumping device. The pumping device includes at least one rough-vacuum pump including a motor for driving the rough-vacuum pump and a variable speed drive to control the rotation speed of the motor, to receive a first input parameter corresponding to a set point frequency and a second input parameter corresponding to a motor current, and to deliver to the motor an output parameter corresponding to a control frequency. A failing operating state is determined when in steady-state operation the difference between the first input parameter and the output parameter is equal to or exceeds 10% of the first input parameter for a predetermined time greater than 3 seconds. The method can be implemented in a pumping device and an installation.