Electric vehicle control apparatus

Claim 2

An electric vehicle control apparatus comprising an electric motor (8) which drives an electric vehicle, a motor controller (7) which controls said motor (8), a filter capacitor (6) connected between said motor controller (7) and a power source, a dynamic braking resistor (12) and a dynamic braking chopper (14) in serial connection connected in parallel to said filter capacitor (6), and means (15) for detecting the voltage of said filter capacitor, characterized in that said apparatus further comprises means of controlling said dynamic braking chopper at electric braking in chopping control mode if the detect voltage value is equal to or greater than a first setup value which is higher than the average voltage of said power source, or in full conduction control mode if the detect voltage value is equal to or greater than a second setup value which is greater than said first setup value.

Claim 3

An electric vehicle control apparatus according to claim 2, characterized in that the means for controlling said dynamic braking chopper at electric braking in full conduction control mode thereafter control it in chopping control mode in case the detected voltage value falls to a value which is equal to or smaller than a third setup value which is equal to or greater than said first setup value and smaller than said second setup value.

Claim 4

An electric vehicle control apparatus according to claim 1, characterized in that the motor controller (7) is an inverter and the electric motor (8) is an induction motor.

Claim 5

An electric vehicle control apparatus comprising an induction motor (8) which drives an electric vehicle, an inverter (7) which controls said induction motor (8), a filter capacitor (6) connected between said inverter (7) and a d.c. power source, a dynamic braking resistor (12) and a dynamic braking chopper (14) in serial connection connected in parallel to said filter capacitor (6), and means (15) for detecting the voltage of said filter capacitor (6), characterized in that said apparatus further comprises means of controlling said dynamic braking chopper in chopping control mode if the detected voltage value is equal to or greater than a first setup value which is higher than the average voltage of said d.c. power source, or in full conduction control mode if the detect voltage value is equal to or greater than a second setup value which is greater than said first setup value, and means of halting the operation of said inverter if a detected voltage value is equal to or greater than said second setup value.

Claim 6

An electric vehicle control apparatus according to one of the claims 1 to 5, characterized in that the chopping control of said dynamic braking chopper is implemented in terms of the conduction ratio in accordance with the detected voltage value.

Claim 7

An electric vehicle control apparatus according to one of the claims 1 to 6, characterized in that the operation of said motor controller (7) is halted in the full conduction control mode.

Claim 8

An electric vehicle control apparatus comprising an induction motor (8) which drives an electric vehicle, an inverter (7) which controls said induction motor (8), a filter capacitor (6) connected between said inverter (7) and a d.c. power source, a dynamic braking resistor (12) and a dynamic braking chopper (14) in serial connection connected in parallel to said filter capacitor (6), and means (15) of detecting the voltage of said filter capacitor (6), characterized in that said apparatus further comprises means of creating a demand of conduction ratio of said dynamic braking chopper if the detected voltage value is equal to or greater than a first setup value which is higher than the average voltage of said d.c. power source, means of creating a demand of full conduction of said dynamic braking chopper during a period after the detected voltage value has become equal to or greater than a second setup value which is greater than said first setup value until the detected voltage value becomes a third value which is equal to or greater than said first setup value and smaller than said second setup value, means of halting the operation of said inverter (7) during the active period of the full conduction demand, and means of opening a line breaker which electrically disconnects said electric vehicle control apparatus from the caterary thereby to activate the air brake of said electric vehicle.

Claim 9

An electric vehicle control apparatus comprising an electric motor (8) which drives an electric vehicle, a motor controller (7) which controls said motor (8), a filter capacitor (6) connected between said motor controller (7) and a power source, a dynamic braking resistor (12) and a dynamic braking chopper (14) in serial connection connected in parallel to said filter capacitor (6), and means (15) of detecting the voltage of said filter capacitor (6), characterized in that said apparatus further comprises means of controlling said dynamic braking chopper at electric braking in at least three divided modes of stopping control, chopping control and full conduction control in correspondence to detected voltage values, said dynamic braking chopper (14) being controlled continuously in transition among said control modes.

Claim 10

An electric vehicle control method, the vehicle comprising an electric motor (8) which drives an electric vehicle, a motor controller (7) which controls said motor (8), a filter capacitor (6) connected between said motor controller (7) and a power source, a dynamic braking resistor (12) and a dynamic braking chopper (14) in serial connection connected in parallel to said filter capacitor (6), and means (15) for detecting the voltage of said filter capacitor (6), characterized by controlling said dynamic braking chopper (14) at electric braking in at least three divided modes of stopping control, chopping control and full conduction control in correspondence to detected voltage values.