Motor drive apparatus and air conditioner
First Claim
Patent Images
1. A motor drive apparatus driving a motor, comprising:
- a plurality of inverter modules equivalent in number to phases of the motor, the inverter modules each including a plurality of switching element pairs connected in parallel, each of the switching element pairs including two switching elements connected in series, the switching element pairs define upper and lower arms including an upper arm and a lower arm, the upper arm being defined by switching elements each being one of the two switching elements, the lower arm being defined by switching elements each being the other of the two switching elements;
a control unit generating a PWM signal used to drive each of the inverter modules with PWM; and
a drive control unit connected to the control unit for replicating the PWM signal to provide a plurality of PWM signals for driving the switching elements of each of the upper and lower arms of a corresponding one of the inverter modules,whereinthe drive control unit changes pulse widths of the plurality of PWM signals by amounts based on a difference in values of currents flowing through the switching elements of each of the upper and lower arms of the corresponding inverter module.
1 Assignment
0 Petitions
Accused Products
Abstract
A motor drive apparatus driving a motor as a three-phase motor converting direct current into three-phase alternating current, includes: inverter modules and equivalent in number to phases of the motor; and a control unit generating PWM signals used to drive the inverter modules with PWM. The inverter modules each include a plurality of switching element pairs connected in parallel, each of the switching element pairs including two switching elements connected in series.
27 Citations
16 Claims
-
1. A motor drive apparatus driving a motor, comprising:
-
a plurality of inverter modules equivalent in number to phases of the motor, the inverter modules each including a plurality of switching element pairs connected in parallel, each of the switching element pairs including two switching elements connected in series, the switching element pairs define upper and lower arms including an upper arm and a lower arm, the upper arm being defined by switching elements each being one of the two switching elements, the lower arm being defined by switching elements each being the other of the two switching elements; a control unit generating a PWM signal used to drive each of the inverter modules with PWM; and a drive control unit connected to the control unit for replicating the PWM signal to provide a plurality of PWM signals for driving the switching elements of each of the upper and lower arms of a corresponding one of the inverter modules, wherein the drive control unit changes pulse widths of the plurality of PWM signals by amounts based on a difference in values of currents flowing through the switching elements of each of the upper and lower arms of the corresponding inverter module. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
-
-
14. A motor drive apparatus driving a motor, comprising:
-
a plurality of inverter modules equivalent in number to phases of the motor, the inverter modules each including a plurality of switching element pairs connected in parallel, each of the switching element pairs including first and second switching elements connected in series, the first switching elements of the respective switching element pairs defining an upper arm, the second switching elements of the respective switching element pairs defining a lower arm; a current measurement unit connected to the switching elements of each of the upper and lower arms of a corresponding one of the inverter modules for measuring currents flowing through the switching elements of each arm; a control unit generating a PWM signal used to drive the inverter modules with PWM; and a drive control unit connected to the control unit for replicating plural PWM signals from the generated PWM signal, the replicated PWM signals turning on or off the switching elements of one of the upper and lower arms of a corresponding one of the inverter modules, wherein when the measured current flowing through a first one of the switching elements of one of the upper and lower arms is larger than the measured currents flowing through the remaining switching elements of the one arm, the drive control unit decreases a pulse width of the replicated PWM signal for turning on or off the first switching element and increases a pulse width of the replicated PWM signal for turning on or off at least one of the remaining switching elements, the amount of the decrease in the pulse width and the amount of the increase in the pulse width being based on a difference between the measured current flowing through the first switching element and the measured current flowing through the at least one of the remaining switching elements. - View Dependent Claims (15, 16)
-
Specification