Disclosed is a method and apparatus for real-time estimation of full parameters of a permanent magnet synchronous motor. According to this method and apparatus, it is possible to estimate in real time all four parameters of a permanent magnet synchronous motor without additional signal injection.

In addition to the state equation, the “stator current ripple model” is additionally used to fundamentally solve the rank deficiency problem in the state equation without injecting additional signals. All four parameters of a permanent magnet synchronous motor can be estimated in real time.

Disclosed is a method and apparatus for real-time estimation of full parameters of a permanent magnet synchronous motor. According to this method and apparatus, it is possible to estimate in real time all four parameters of a permanent magnet synchronous motor without additional signal injection.

In addition to the state equation, the “stator current ripple model” is additionally used to fundamentally solve the rank deficiency problem in the state equation without injecting additional signals. All four parameters of a permanent magnet synchronous motor can be estimated in real time.

A method of monitoring electrical loads is disclosed. In an embodiment the method includes generating a first voltage signal and a second voltage signal, the second voltage signal in quadrature to the first voltage signal, injecting one of the first voltage signal or the second voltage signal into a signal propagation path towards an electrical load, sensing a current signal flowing through the electrical load as a result of the one of the first voltage signal or the second voltage signal injected into the signal propagation path and processing the first voltage signal, the second voltage signal and the sensed current signal.

A fault protection arrangement. The fault protection arrangement may include a neutral grounding resistor including a first non-ground end, connected to a neutralizing point, and a second non-ground end. The fault protection arrangement may include a neutral grounding resistance monitor assembly, directly coupled to the second non-ground end of the neutral grounding resistor. The neutral grounding resistance monitor assembly may include comprising a signal source coupled to the neutralizing-point; a first current sense circuit coupled between the signal source and the neutralizing-point; a first voltage sense circuit coupled between the signal source and the neutralizing-point; a second current sense circuit, comprising a current sensor, coupled between the second non-ground end of the neutral grounding resistor and a protective earth connection.

The present invention relates to a method for estimating individual phase resistance of a motor by means of an adjustable speed drive (ASD) while the motor controlled by the ASD is running and/or is at standstill. The motor is an asynchronous motor or a synchronous motor. The invention also relates to an adjustable speed drive for executing a corresponding method.

Methods and systems for compensating display panel operations providing a current from power circuitry over a first path between a display panel and the power circuitry are provided. A sensing current may be injected into the first path via a second path between the power circuitry and the first path. An equivalent series resistance (ESR) of the first path may be calculated using a third path and the sensing current. A processor may compensate for electrical fluctuations from the power circuitry to the display panel based at least in part on the measured ESR.

Methods and systems for compensating display panel operations providing a current from power circuitry over a first path between a display panel and the power circuitry are provided. A sensing current may be injected into the first path via a second path between the power circuitry and the first path. An equivalent series resistance (ESR) of the first path may be calculated using a third path and the sensing current. A processor may compensate for electrical fluctuations from the power circuitry to the display panel based at least in part on the measured ESR.

An insulation resistance measurement apparatus includes a first resistance unit having one end connected to an anode of a battery and the other end connected to ground, and variably having a first resistance value or a second resistance value greater than the first resistance; a second resistance unit having one end connected to a cathode of the battery and the other end connected to ground, and variably having a third resistance value or a fourth resistance value greater than the third resistance value according to control; a voltage measurement unit configured to measure a voltage across the first or second resistance unit; and an insulation resistance calculation unit configured to calculate a first insulation resistance value between the anode of the battery and ground and a second insulation resistance value between the cathode of the battery and ground by using the first to fourth resistance values and the measured voltage.

An insulation resistance measurement apparatus includes a first resistance unit having one end connected to an anode of a battery and the other end connected to ground, and variably having a first resistance value or a second resistance value greater than the first resistance; a second resistance unit having one end connected to a cathode of the battery and the other end connected to ground, and variably having a third resistance value or a fourth resistance value greater than the third resistance value according to control; a voltage measurement unit configured to measure a voltage across the first or second resistance unit; and an insulation resistance calculation unit configured to calculate a first insulation resistance value between the anode of the battery and ground and a second insulation resistance value between the cathode of the battery and ground by using the first to fourth resistance values and the measured voltage.

In various embodiments, a graphical plotter can create a transformation circle. An identification component can identify a center point, a radius from the center point, and a circular outer point set extended from the center point by the radius. A creation component can create a plot based, at least in part, on the center point, the radius, and the circular outer point set. An output component can cause the plot to be outputted, where the circular outer point set is dependent on trigonometry of an angle set from an x-axis pertaining to the center point and the radius.