Abstract: An apparatus and method for controlling the maximum stroke of a linear compressor is provided. The shorting of the normal supply voltage of a compressor to ground is used to detect overstroking. A plurality of transistors are electrically coupled to the control circuit that is electrically coupled to a linear compressor. When the compressor's stroke exceeds it maximum stroke marked by the refrigerant barrel of the compressor making physical contact with the armature, a signal is received by the control circuit. The control circuit processes this signal and sequences the transistors to return the extended stroke of the compressor to its maximum stroke.

Abstract: An apparatus and method for controlling the maximum stroke of a linear compressor is provided. The shorting of the normal supply voltage of a compressor to ground is used to detect overstroking. A plurality of transistors are electrically coupled to the control circuit that is electrically coupled to a linear compressor. When the compressor's stroke exceeds it maximum stroke marked by the refrigerant barrel of the compressor making physical contact with the armature, a signal is received by the control circuit. The control circuit processes this signal and sequences the transistors to return the extended stroke of the compressor to its maximum stroke.

Abstract: An electrical driver (10) for a linear electrical motor which drives a linear refrigerant compressor (11) that has a resonant frequency includes a sensor (22) for measuring the magnitude and polarity of the back EMF of the electrical motor at the beginning and/or end of the stroke of the compressor (11). A control circuit (12) analyses the measured back EMF to determine whether the driver frequency is higher or lower than the frequency of the compressor (11) and then adjusts the frequency of the driver (10) to or closer to the resonant frequency of the compressor (11).

Abstract: A high efficiency power conversion at high frequencies with zero voltage switching is obtained by using magnetizing current of a transformer or parallel inductance to charge the switch adjunct capacitance and other capacitance during the dead time. A transformer is prevented from being loaded during the dead time. Loading of the transformer during the dead time is prevented by directing the output inertial current to a capacitor instead of through the rectifiers to the secondary of the transformer. This can also be achieved by using synchronized rectification that provides pulse width modulated regulation on the output and ensures that the transformer secondary is separated from the inertial current of the output during the dead time. Voltage and current stresses on the switching devices and rectifiers are minimized. Zero voltage switching may be applied to inverters where the load is resistive.