초록 ▼

An electromechanical power transfer system that transfers power between a direct current (DC) electrical power system and a prime mover, comprises: a permanent magnet machine (PMM) comprising a permanent magnet (PM) rotor that rotates a drive shaft of the prime mover, a stator and a control coil; th

An electromechanical power transfer system that transfers power between a direct current (DC) electrical power system and a prime mover, comprises: a permanent magnet machine (PMM) comprising a permanent magnet (PM) rotor that rotates a drive shaft of the prime mover, a stator and a control coil; that an inverter/rectifier system for converting DC power from the DC power system to multiphase alternating current (AC) power on an AC bus; a control coil current regulator system for regulating current through the control coil; wherein the inverter/rectifier system responds to a position reference signal, a current load feedback signal and a current load reference signal to regulate acceleration of the PMM; wherein the control coil current regulator system responds to a control coil current reference signal and a control coil current feedback signal to regulate current in the PMM; and wherein the power transfer system starts in an open loop mode, and the first and second speed switches respond to a closed loop enable mode to switch from their open loop mode to their closed loop mode.

대표청구항 ▼

The claimed invention is: 1. An electromechanical power transfer system that transfers power between a direct current (DC) electrical power system and a prime mover, comprising: a permanent magnet machine (PMM) comprising a permanent magnet (PM) rotor that rotates a drive shaft of the prime mover,

The claimed invention is: 1. An electromechanical power transfer system that transfers power between a direct current (DC) electrical power system and a prime mover, comprising: a permanent magnet machine (PMM) comprising a permanent magnet (PM) rotor that rotates a drive shaft of the prime mover, a stator with a multiphase alternating current (AC) winding coupled to the AC bus for developing a rotating magnetic field with a magnetic flux path that causes rotation of the PM rotor and a control coil with a winding that has a configuration to generate a magnetic field with flux that varies the reactance of the stator winding upon the application of current through the control coil; a plurality of AC current sensors for sensing the current in each phase of the multi-phase AC bus and generating respective AC bus current signals that represent the current level of each phase; an average current detector that receives the AC bus current signals and generates a respective current load feedback signal; a back electromotive force (emf) detector coupled to the AC bus that detects back emf generated by the stator in response to the application of AC power to the stator and generates a back emf signal representative of the detected level of back emf; a rotor position/speed estimator that receives the back emf signal and generates an estimated rotor position signal that is representative of the position of the rotor, an estimated rotor speed signal that is representative of the speed of the rotor and a closed loop enable signal that indicates a speed for the electrical starting system to switch from an open loop mode of operation to a closed loop mode of operation; a control coil current sensor for generating a control coil current signal in a control coil current feedback loop that is representative of the level of electrical current in the control coil; a first speed switch that switches between an open loop position reference signal that represents a desired position of the rotor in an open loop mode and the estimated rotor position signal that represents the position of the rotor in a closed loop mode to provide a position reference signal; a second speed switch that switches between an open loop current reference signal that represents a desired control coil current level in the open loop mode and a closed loop current reference signal that represents a desired control coil current level in the closed loop mode to provide a control coil current reference signal; an inverter/rectifier system for converting DC power from the DC power system to multiphase alternating current (AC) power on an AC bus; a control coil current regulator system for regulating current through the control coil; wherein the inverter/rectifier system responds to the position reference signal, the current load feedback signal and a current load reference signal to regulate acceleration of the PMM; wherein the control coil current regulator system responds to the control coil current reference signal and the control coil current feedback signal to regulate current in the PMM; and wherein the power transfer system starts in the open loop mode, the rotor position/speed estimator generates the closed loop enable signal that indicates a speed for the electrical starting system to switch from the open loop mode of operation to the closed loop mode of operation at a predetermined rotor speed, and the first and second speed switches respond to the closed loop enable mode to switch from their open loop mode to their closed loop mode. 2. The power transfer system of claim 1, wherein the inverter/rectifier system comprises: a multiphase inverter/rectifier circuit that provides multiphase AC power to the AC bus; a commutation look-up table that receives the position reference signal and generates a corresponding sector position signal; an inverter circuit comparator for comparing the current load feedback signal with a current load reference signal and generating an AC bus current error signal that is representative of the difference between the current load feedback signal and the current load reference signal; an inverter circuit proportional integral (PI) controller for receiving the AC bus current error signal and generating a corresponding inverter duty cycle signal; and an inverter circuit modulator for receiving the sector position signal and the inverter duty cycle signal to generate a corresponding plurality of inverter circuit modulator signals that control the frequency and duty cycle of the inverter/rectifier circuit. 3. The power transfer system of claim 1, wherein the control coil current regulator system comprises: a control coil current error comparator for comparing the control coil current signal with the reference control coil current signal and generating a control coil current error signal representative of the difference between the control coil current signal and the reference control coil current signal; a control coil current error PI controller for receiving the control coil current error signal and generating a corresponding control coil current modulator drive signal; a control coil circuit modulator for receiving the control current modulator drive signal and generating a corresponding plurality of control coil circuit modulator signals; and a control coil current regulator circuit that receives the control coil circuit modulator signals and supplies the control coil with current that has a level that varies in response to the control coil circuit modulator signals. 4. The power transfer system of claim 1, further comprising a control coil circuit look-up table that receives the estimated rotor speed signal and generates a corresponding value for the closed loop current reference signal. 5. The power transfer system of claim 1, further comprising: a 1/S integration function for receiving an open loop acceleration reference signal that represents desired open loop rate of acceleration for the rotor in the open loop mode and generating a corresponding open loop speed reference signal; and a 1/S mod2n integral function for receiving the open loop speed reference signal and generating the open loop position reference signal. 6. The power transfer system of claim 1, further comprising: a 1/Kt reciprocal torque function that receives a torque reference signal and generates the current load reference signal. 7. The power transfer system of claim 2, further comprising: an inverter circuit gates drive module for receiving the inverter circuit modulator signals and generating a corresponding plurality of inverter circuit gates drive signals that operate the inverter/rectifier circuit. 8. The power transfer system of claim 3, further comprising: a control coil circuit gates drive module for receiving the control circuit modulator signals and generating a corresponding plurality of control circuit gates drive signals that operate the control coil current regulator circuit. 9. The power transfer system of claim 2, wherein the inverter circuit modulator comprises a pulse width modulator (PWM). 10. The power transfer system of claim 3, wherein the control circuit modulator comprises a pulse width modulator (PWM). 11. The power transfer system of claim 1, wherein the power transfer system comprises an electrical starting system for the prime mover. 12. The power transfer system of claim 11, wherein the power transfer system comprises an electrical generating system powered by the prime mover. 13. An electromechanical power transfer system that transfers power between a direct current (DC) electrical power system and a prime mover, comprising: a permanent magnet machine (PMM) comprising a permanent magnet (PM) rotor that rotates a drive shaft of the prime mover, a stator with a multiphase alternating current (AC) winding coupled to the AC bus for developing a rotating magnetic field with a magnetic flux path that causes rotation of the PM rotor and a control coil with a winding that is capable of generating a magnetic field with flux that varies the reactance of the stator winding upon the application of current through the control coil; a plurality of AC current sensors for sensing the current in each phase of the multi-phase AC bus and generating respective AC bus current signals that represent the current level of each phase; an average current detector that receives the AC bus current signals and generates a respective current load feedback signal; a back electromotive force (emf) detector coupled to the AC bus that detects back emf generated by the stator in response to the application of AC power to the stator and generates a back emf signal representative of the detected level of back emf; a rotor position/speed estimator that receives the back emf signal and generates an estimated rotor position signal that is representative of the position of the rotor, an estimated rotor speed signal that is representative of the speed of the rotor and a closed loop enable signal that indicates a speed for the electrical starting system to switch from an open loop mode of operation to a closed loop mode of operation; a control coil current sensor for generating a control coil current signal in a control coil current feedback loop that is representative of the level of electrical current in the control coil; a first speed switch that switches between an open loop position reference signal that represents a desired position of the rotor in an open loop mode and the estimated rotor position signal that represents the position of the rotor in a closed loop mode to provide a position reference signal; a second speed switch that switches between an open loop current reference signal that represents a desired control coil current level in the open loop mode and a closed loop current reference signal that represents a desired control coil current level in the closed loop mode to provide a control coil current reference signal; a multiphase inverter/rectifier circuit that provides multiphase AC power to the AC bus; a commutation look-up table that receives the position reference signal and generates a corresponding sector position signal; an inverter circuit comparator for comparing the current load feedback signal with a current load reference signal and generating an AC bus current error signal that is representative of the difference between the current load feedback signal and the current load reference signal; an inverter circuit proportional integral (PI) controller for receiving the AC bus current error signal and generating a corresponding inverter duty cycle signal; and an inverter circuit modulator for receiving the sector position signal and the inverter duty cycle signal to generate a corresponding plurality of inverter circuit modulator signals that control the frequency and duty cycle of the inverter/rectifier circuit; a control coil current error comparator for comparing the control coil current signal with the reference control coil current signal and generating a control coil current error signal representative of the difference between the control coil current signal and the reference control coil current signal; a control coil current error PI controller for receiving the control coil current error signal and generating a corresponding control coil current modulator drive signal; a control coil circuit modulator for receiving the control current modulator drive signal and generating a corresponding plurality of control coil circuit modulator signals; and a control coil current regulator circuit that receives the control coil circuit modulator signals and supplies the control coil with current that has a level that varies in response to the control coil circuit modulator signals; wherein the inverter/rectifier circuit responds to the position reference signal, the current load feedback signal and a current load reference signal to regulate acceleration of the PMM; wherein the control coil current regulator circuit responds to the control coil current reference signal and the control coil current feedback signal to regulate current in the PMM; and wherein the power transfer system starts in the open loop mode, the rotor position/speed estimator generates the closed loop enable signal that indicates a speed for the electrical starting system to switch from the open loop mode of operation to the closed loop mode of operation at a predetermined rotor speed, and the first and second speed switches respond to the closed loop enable mode to switch from their open loop mode to their closed loop mode. 14. The power transfer system of claim 13, further comprising a control coil circuit look-up table that receives the estimated rotor speed signal and generates a corresponding value for the closed loop current reference signal. 15. The power transfer system of claim 13, further comprising: a 1/S integration function for receiving an open loop acceleration reference signal that represents desired open loop rate of acceleration for the rotor in the open loop mode and generating a corresponding open loop speed reference signal; and a 1/S mod2n integral function for receiving the open loop speed reference signal and generating the open loop position reference signal. 16. The power transfer system of claim 13, further comprising: a 1/Kt reciprocal torque function that receives a torque reference signal and generates the current load reference signal. 17. The power transfer system of claim 13, further comprising: an inverter circuit gates drive module for receiving the inverter circuit modulator signals and generating a corresponding plurality of inverter circuit gates drive signals that operate the inverter/rectifier circuit. 18. The power transfer system of claim 13, further comprising: a control coil circuit gates drive module for receiving the control circuit modulator signals and generating a corresponding plurality of control circuit gates drive signals that operate the control coil current regulator circuit. 19. The power transfer system of claim 13, wherein the inverter circuit modulator comprises a pulse width modulator (PWM). 20. The power transfer system of claim 13, wherein the control circuit modulator comprises a pulse width modulator (PWM). 21. The power transfer system of claim 13, wherein the power transfer system comprises an electrical starting system for the prime mover. 22. The power transfer system of claim 21, wherein the power transfer system comprises an electrical generating system powered by the prime mover. 23. A method of transferring power between a direct current (DC) electrical power system that comprises an inverter/rectifier system coupled between an alternating current (AC) bus and a DC bus and a prime mover by means of a permanent magnet machine (PMM) that has a PM rotor coupled to the prime mover and a stator with a multiphase AC winding coupled to the AC bus, comprising the steps of: generating a magnetic field with flux that varies the reactance of the stator winding upon the application of current through the control coil; generating AC bus current signals for each phase of the AC bus that represent the current level of each phase; generating a current load feedback signal that represents the average current of the AC bus current signals; generating a back emf signal that is representative of the level of back emf that the stator generates in response to the application of AC power; generating an estimated rotor position signal that is representative of the position of the rotor, an estimated rotor speed signal that is representative of the speed of the rotor and a closed loop enable signal that indicates a speed for the electrical starting system to switch from an open loop mode of operation to a closed loop mode of operation; generating a control coil current signal in a control coil current feedback loop that is representative of the level of electrical current in the control coil; a first switching process to switch between an open loop position reference signal that represents a desired position of the rotor in an open loop mode and the estimated rotor position signal that represents the position of the rotor in a closed loop mode to provide a position reference signal; a second switching process to switch between an open loop current reference signal that represents a desired control coil current level in the open loop mode and a closed loop current reference signal that represents a desired control coil current level in the closed loop mode to provide a control coil current reference signal; an inverter/rectifier system for converting DC power from the DC power system to multiphase alternating current (AC) power on an AC bus; a control coil current regulator system for regulating current through the control coil; wherein the inverter/rectifier system responds to the position reference signal, the current load feedback signal and a current load reference signal to regulate acceleration of the PMM; wherein the control coil current regulator system responds to the control coil current reference signal and the control coil current feedback signal to adjust control coil current that regulates current level in the PMM; and wherein the power transfer process starts in the open loop mode by generating the closed loop enable signal that indicates a speed for the power transfer process to switch from the open loop mode of operation to the closed loop mode of operation at a predetermined rotor speed, and the first and second switching processes respond to the closed loop enable mode to switch from their open loop mode to their closed loop mode. 24. The power transfer process of claim 23, wherein the power transfer process comprises a process for starting the prime mover. 25. The power transfer process of claim 23, wherein the power transfer process further comprises the transfer of power from the prime mover to the electrical power system.