An electromobile includes a motor; an output torque cutting commanding circuit for commanding the cutting of the output torque of the motor responsive to detection of a predetermined condition; and output torque command calculator for calculating an output torque command corresponding to the speed and accelerator opening of the electromobile and changing its output torque command to a value for stopping the motor in response to a command from the output torque cutting commanding circuit. A motor driving circuit feeds a motor current to the motor in accordance with the output torque command which is calculated by the output torque command calculator; and an output torque cutting circuit, packaged in the motor driving circuit for cutting the output torque of the motor in direct response to the command of the torque cutting commanding circuit.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to an electromobile (electric car) in which 
an internal combustion engine is replaced by an electric motor to reduce 
noises and eliminate emission of the engine exhaust gases. 
2. Description of the Prior Art 
The electromobile is run by the output torque produced by an electric motor 
to which a motor current is fed from a battery. 
In a brushless motor composed of a rotor made of a permanent magnet and a 
stator coil, three-phase sinusoidal waves are generated corresponding to 
the-positions of the magnetic poles of the rotor. A current command is 
superposed on the sinusoidal waves by a motor controller to produce a PWM 
signal, which is converted into a sinusoidal phase current, i.e. a motor 
current, by an inverter circuit and is fed to the motor. 
FIG. 2 is a block diagram showing an electromobile of the prior art. In 
FIG. 2 reference numeral 21 designates a shift switch for detecting the 
range position selected by the driver's manipulation of a shift lever 
(not-shown), i.e. the position of the shift lever. Numeral 22 represents a 
CPU equipped with RAM, ROM and the like for controlling the electromobile 
in its entirety; numeral 23 a motor controller for producing three-phase 
sinusoidal waves corresponding to the magnetic pole positions of the rotor 
to produce the PWM signal by superposing a current command upon the 
sinusoidal waves; and numeral 24 an inverter circuit composed of a 
plurality of power transistors for converting the PWM signal produced by 
the motor controller 23 into a motor current having the sinusoidal waves 
and fed to a motor 25. Numeral 26 designates a battery. 
In the electromobile thus constructed, the output torque of the motor 25 is 
controlled by changing the current command also referred to as the output 
torque command. Moreover, the motor current is fed back to match the 
current command. 
If neutral (N) or parking (P) is selected in the electromobile of this 
kind, the CPU 22 outputs a torque command to set the output torque to O. 
In the electromobile in which the wheel axle and the motor 25 are directly 
connected, there is no means for disconnecting the axle from the motor 25. 
Thus, it is decided by the CPU 22 whether or not the drive wheels are to 
be rotated. 
FIG. 3 is a schematic diagram showing an electromobile of the prior art, in 
which the axle and the motor are directly connected. In FIG. 3 reference 
numeral 21 designates a shift switch; numeral 22 a CPU numeral 23 a motor 
controller; numeral 24 an inverter circuit (INV); numeral 25 a motor; and 
numeral 27 drive wheels. The inverter circuit 24 converts the PWM signal 
produced by the motor controller 23 into the motor current and feeds the 
motor current to the motor 25. In this case, the CPU 22 outputs the drive 
signal to the inverter circuit 24 so that the motor 25 is energized to 
drive the drive wheels 27 when the drive signal is ON. 
In the electromobile of the prior art described above, however, the CPU 22 
calculates the output torque command and produces the drive signal. In 
case of a malfunction in the motor controller 23, in the switching 
elements of the inverter circuit 4 or in the CPU 22, therefore, it may be 
impossible to sufficiently control the motor current fed to the motor 25 
or to set the output torque command to O. 
SUMMARY OF THE INVENTION 
An object of the present invention is to solve the aforementioned problems 
concomitant with the electromobile of the prior art and to provide an 
electromobile which can properly control the motor current fed to the 
motor. 
In order to achieve the above-specified object, according to one aspect of 
the present invention, there is provided an electromobile including a 
motor; output torque cut commanding means for commanding the cutting of 
the output torque of the motor under a predetermined condition; output 
torque command calculating means for calculating an output torque command 
corresponding to the speed and accelerator opening of the electromobile 
and changing its output torque command to a value for stopping the motor 
in response to a command from the output torque cut commanding means; and 
a motor driving circuit for feeding a motor current to the motor in 
response to the output torque command which is calculated by the output 
torque command calculating means. Output torque cutting means is packaged 
in the motor driving circuit for cutting the output torque of the motor in 
direct response to the command of the torque cut commanding means. 
In a normal state, therefore, the output torque command is calculated 
according to the vehicle speed and accelerator opening of the 
electromobile and is fed to the motor driving circuit to drive the motor. 
If the predetermined condition is satisfied by selection of the neutral 
range or the parking range, the output torque cut commanding means 
commands the output torque command calculating means to cut the output 
torque of the motor. In response to the command of the output torque cut 
commanding means, the output torque command calculating means sets the 
output torque command to O, for example, to stop the motor. 
The motor driving circuit is packaged in the output torque cutting means. 
In response to the command of the output torque cut commanding means, this 
output torque cutting means cuts the out-put torque of the motor. In this 
case, the command of the output torque cut commanding means is fed 
directly, i.e., not through the output torque command calculating means or 
the like, to the output torque cutting means so that the motor can be 
stopped even if the switching elements or the CPU malfunction. 
According to another aspect of the present invention, there is provided an 
electromobile which includes a motor; a shift switch for detecting a range 
selected by a driver; a CPU for calculating an output torque command 
corresponding to the vehicle speed and the accelerator opening of the 
electromobile; a motor controller for outputting a signal for controlling 
the motor in response to the signal coming from the CPU; an inverter 
circuit for converting the signal of the motor controller into a motor 
current output to the motor; and torque cutting means connected between 
the shift switch and the inverter circuit for outputting a motor stopping 
signal directly to the inverter circuit in response to a torque cutting 
signal from the shift switch. 
According to still another aspect of the present invention, the torque 
cutting means is replaced by a drive signal interrupting circuit connected 
between the motor controller and the inverter circuit for outputting a 
motor stopping signal directly to the inverter circuit in response to a 
torque cutting signal from the shift switch or the CPU.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Several preferred embodiments of the present invention will be described in 
detail with reference to the accompanying drawings. 
In FIG. 1, reference numeral 25 designates a motor connected to drive 
wheels (not-shown), and numeral 32 designates output torque cut commanding 
means for commanding the cutting of output torque generated by the motor 
25. The output torque cut commanding means 32 is exemplified by a neutral 
switch or a parking switch to be turned ON or OFF by manipulating a shift 
lever (not-shown), or a manual switch to be turned ON or OFF by hand 
manipulation. 
Reference numeral 15 designates a output torque command calculating means 
which is packaged in a CPU 22 (as shown in FIG. 2) and which responds to 
vehicle speed and accelerator opening detected by a vehicle speed sensor 
and an accelerator sensor (not shown), for calculating an output torque 
command according to those values. Numeral 34 designates a motor driving 
circuit for generating and feeding a motor current to the motor 25; 
numeral 35 a signal delay circuit; and numeral 36 a current interrupting 
mechanism acting as output torque cutting means, which is disposed in the 
motor driving circuit 34 for cutting output torque in response to the 
output torque cutting command signal a of the output torque cut commanding 
means 32. 
In the motor drive control circuit thus constructed, the output torque 
command calculating means 15 calculates the output torque command from the 
detected vehicle speed and the detected accelerator opening and outputs an 
output torque command signal c to the motor driving circuit 34. The motor 
driving circuit 34 drives the motor 25 responsive to the output torque 
command. 
If the driver manipulates the shift lever or the manual switch directly, to 
select the neutral or parking range and to command the cutting of the 
output torque, the output torque cut commanding means 32 outputs the 
output torque cutting command signal a. In response to this output torque 
cutting command signal a, the output torque command calculating means 15 
sets the output torque command to a value such as 0 to stop the motor 25. 
In response to the output torque command, the motor driving circuit 34 
interrupts the feed of the motor current to the motor 25. 
On the other hand, the output torque cut commanding means 32 is connected 
through the signal delay circuit 35 with the current interrupting 
mechanism 36 in the motor driving circuit 34 so that it outputs the output 
torque cutting command signal a directly to the current interrupting 
mechanism 36, not through the CPU 22. As a result, the motor 25 can be 
stopped without fail by the output torque cutting command signal a even if 
the output torque command calculating means 15 or the motor driving 
circuit 34 should malfunction. 
In the present invention, if the motor current is interrupted, the cutting 
of the output torque were to be commanded instantly during the running of 
the electromobile, so that the output torque is abruptly cut, a shock 
would result. Therefore, between the output torque cut commanding means 32 
and the current interrupting mechanism 36, is connected a hardware signal 
delay circuit 35, by which the output torque cutting command signal a is 
delayed by a delay time t to produce a motor current output signal b, so 
that this motor current output signal b is input to the current 
interrupting mechanism 36. 
Moreover, the output torque cut commanding means 32 is further connected 
with the output torque command calculating means 15 so that the output 
torque cutting command signal a is also input to the output torque command 
calculating means 15. This output torque command calculating means 15 
ordinarily calculates the output torque command from the vehicle speed or 
the accelerator opening and outputs the calculated command to the motor 
driving circuit 34. In response to the output torque cutting command 
signal a, however, the output torque command calculating means 15 
decreases the output torque command gradually by its software to set the 
output torque command to 0 over the aforementioned delay time t. 
As a result, the motor driving circuit 34 feeds the motor 25 with a motor 
current corresponding to the output torque command so that the abrupt 
fluctuation of the output torque can be eliminated to prevent any shock. 
As illustrated in FIG. 5 motor drive control is effected by the motor 
driving circuit 34 as follows: 
Step S11: 
The routine is initialized. 
Step S12: 
Signals of the vehicle speed, the accelerator opening and the like are 
inputted. 
Step S13: 
The output torque control executed, and the routine returned to Step S12. 
In FIG. 6: reference letter R designates a resistor; letter C a capacitor; 
letter D a diode; and letters IC an amplifier. In this case, when the 
output torque cutting command signal a is inputted, a delay signal a.sub.d 
is generated between the resistor R and the amplifier IC so that the motor 
current output signal b is output from the output terminal of the 
amplifier IC. By slicing the delay signal a.sub.d at a predetermined 
level, moreover, it is possible to obtain the delay time t, as shown in 
FIG. 7. This delay time t may be set to a larger value than the time for 
decreasing the output torque command gradually from maximum to 0, as shown 
in FIG. 8. Here, the delay time t is expressed by the following formula: 
EQU t=-R.multidot.C.multidot.log (1-V.sub.ICON /V.sub.CC), 
V.sub.ICON : Input voltage when the amplifier IC is at the high level; and 
V.sub.CC : Voltage when the output torque cutting command signal a is at 
the high level. 
Here will be described a transient torque control for decreasing the output 
torque command gradually in the first embodiment of the present invention. 
It is assumed that the output torque command calculated from the detected 
vehicle speed and the detected accelerator opening, i.e., the target 
torque is designated T.sub.1, the output torque command of the previous 
time (hereinafter "previous command") is designated T.sub.0, and the 
output torque command to be actually issued at this time (hereinafter 
"present command") is designated T.sub.out. Then, the difference between 
the previous command T.sub.0 and the target torque T.sub.1, i.e., the 
command difference .DELTA. T is expressed by: 
EQU .DELTA.T=T.sub.1 -T.sub.0. 
Moreover, the target torque T.sub.1 is used as is as the present command 
T.sub.out if the command difference .DELTA. T is within a predetermined 
range, but the change in the output torque command is reduced if the range 
is exceeded. This control flow is illustrated in FIG. 9 as follows: 
Step S21: 
It is decided whether or not the selected range is in the neutral range or 
the parking range. The routine advances to Step S22, if the answer is YES, 
but otherwise to Step S23. 
Step S22: 
The target torque T.sub.1 is set to 0. 
Step S23: 
The target torque T.sub.1 is calculated from the vehicle speed and the 
accelerator opening. 
Step S24: 
The absolute value of the command difference .DELTA. T between the previous 
command T.sub.0 and the target torque T.sub.1 is compared with the 
absolute value .DELTA. T.sub.max of the command difference .DELTA. T. 
The routine advances to Step S25, if 
EQU .vertline.T.sub.0 -T.sub.1 
.vertline.=.vertline..DELTA.T.vertline.&lt;.DELTA.T.sub.max. 
The routine advances to Step S26, if 
EQU .vertline.T.sub.0 -T.sub.1 
.vertline.=.vertline..DELTA.T.vertline..gtoreq..DELTA.T.sub.max, 
and if 
EQU .DELTA.T&gt;. 
The routine advances to Step S27, if 
EQU .vertline.T.sub.0 -T.sub.1 
.vertline.=.vertline..DELTA.T.vertline..gtoreq.T.sub.max, 
and if 
EQU .DELTA.T&lt;0. 
Step S25: 
The present command T.sub.out is set to target torque T.sub.1, i.e., the 
addition of the command difference .DELTA. T to the previous command 
T.sub.0 Step 
Step S26: The present command T.sub.out is set to the sum of the maximum 
.DELTA. T.sub.max of the command difference .DELTA. T and the previous 
command T.sub.0. 
Step S27: The previous command T.sub.out is set by subtraction of the 
maximum .DELTA. T.sub.max of the command difference .DELTA. T from the 
previous command T.sub.0. 
In another transient torque control, on the other hand, the abrupt 
fluctuation of the output torque can be further reduced to prevent shock 
by satisfying the following formulas: 
EQU D=T.sub.1 -T.sub.0 =.DELTA. T; 
and 
EQU T.sub.out =T.sub.0 +D/4. 
However, if the target torque T.sub.1 has an extremely high changing rate, 
the upper limit of the value D is set to 10/32 [ms]. In this manner, it is 
possible to accomplish the transient torque control shown in FIG. 10. 
A second embodiment of the present invention will now be described with 
reference to FIG. 11. In FIG. 11 reference numeral 21 designates a shift 
switch; numeral 22 a CPU; numeral 23 a motor controller; numeral 24 an 
inverter circuit; numeral 25 a motor; numeral 26 a battery; and numeral 28 
a drive signal interrupting circuit acting as output torque cutting means 
connected between the motor controller 23 and the inverter circuit 24. 
In this case, the PWM signal generated by the motor controller 23 is output 
to the inverter circuit 24 so that it may be changed into a sinusoidal 
wave motor current. When the output torque cut command signal a is output 
from the CPU 22, the drive signal interrupting circuit 28, if connected 
between the controller 23 and the inverter circuit 24, interrupts the 
output of the PWM signal. Then, the output torque cutting command signal a 
is output directly to the drive signal interrupting circuit 28, not 
through the motor controller 23. As a result, the motor 25 can be stopped 
without fail by the output torque cut command signal a even if the motor 
controller 23 malfunctions. 
A third embodiment of the present invention will now be described with 
reference to FIG. 12. In FIG. 12 reference numeral 21 designates a shift 
switch; numeral 22 a CPU; numeral 23 a motor controller; numeral 24 an 
inverter circuit; numeral 25 a motor; numeral 26 a battery; and numeral 29 
a current interrupting mechanism, acting as the output torque cutting 
means, connected between the battery 26 and the inverter circuit 24. 
In this case, the PWM signal generated by the motor controller 23 is output 
to the inverter circuit 24 so that it may be changed into a sinusoidal 
wave motor current. If the output torque cut command signal a is output 
from the CPU 22, the current interrupting mechanism 29, if connected 
between the battery 26 and the inverter circuit 24, interrupts the current 
feed from the battery 26. Then, the output torque cutting command signal a 
is output directly to the current interrupting mechanism 29, not through 
the motor controller 23. As a result, the motor 25 can be stopped without 
fail by the output torque cut command signal a even if the motor 
controller 23 malfunctions. 
A fourth embodiment of the present invention will now be described with 
reference to FIG. 13. In FIG. 13 reference numeral 21 designates a shift 
switch; numeral 22 a CPU; numeral 23 a motor controller; numeral 24 an 
inverter circuit; numeral 25 a motor; numeral 26 a battery; and numeral 28 
a drive signal interrupting circuit, acting as output torque cutting 
means, connected between the motor controller 23 and the inverter circuit 
24. 
In this case, the PWM signal generated by the motor controller 23 is output 
to the inverter circuit 24 so that it may be changed into a sinusoidal 
wave motor current. If a first output torque cut command signal a.sub.1 is 
output from the CPU 22 and if a second output torque cut command signal 
a.sub.2 is output from the shift switch 21, the drive signal interrupting 
circuit 28, if connected between the controller 23 and the inverter 
circuit 24, interrupts the output of the PWM signal. Then, the first 
output torque cutting command signal a.sub.1 is output directly to the 
drive signal interrupting circuit 28, not through the motor controller 23. 
As a result, the motor 25 can be stopped without fail by the first output 
torque cut command signal a.sub.1 even if the motor controller 23 
malfunctions. On the other hand, the second output torque cut command 
signal a.sub.2 is output directly to the drive signal interrupting circuit 
28, not through the CPU 22 and the motor controller 23. As a result, even 
if the switching circuit of the CPU 22 or the inverter malfunctions, the 
motor 25 can be stopped without fail by the second output torque cutting 
command signal a.sub.2 if the driver moves the shift lever to a non-drive 
range such as the N-range or the P-range. 
A fifth embodiment of the present invention will now be described with 
reference to FIG. 14. In FIG. 14 reference numeral 21 designates a shift 
switch; numeral 22 a CPU; numeral 23 a motor controller; numeral 24 an 
inverter circuit; numeral 25 a motor; and numeral 27 drive wheels. The 
inverter circuit 24 converts the PWM signal generated by the motor 
controller 23 into the motor current and feeds the motor current to the 
motor 25 to rotate the drive wheels 27. In this case, the first output 
torque cut command signal a.sub.1 and the second output torque cut command 
signal a.sub.2 are respectively output from the CPU 22 and the shift 
switch 21 to an OR gate 51 so that the output torque cut command signal a 
is output from the OR gate 51 to the inverter circuit 24. In response to 
the output torque cut command signal a, the inverter circuit 24 interrupts 
the feed of the motor current to the motor 25. 
Moreover, the first output torque cut command signal a.sub.1 is output 
directly to the inverter circuit 24, not through the motor controller 23. 
As a result, the motor 25 can be stopped without fail by the output torque 
cut command signal a even if the motor controller 23 malfunctions. On the 
other hand, the second output torque cut command signal a.sub.2 is output 
directly to the inverter circuit 24, not through the CPU 22 and the motor 
controller 23. As a result, the motor 25 can be stopped without fail by 
the output torque cutting command signal a even if the CPU 22 
malfunctions. 
A sixth embodiment of the present invention will now be described with 
reference to FIG. 15. In FIG. 15 reference numeral 21 designates a shift 
switch; numeral 22 a CPU; numeral 23 a motor controller; numeral 24 an 
inverter circuit; numeral 25 a motor; numeral 26 a battery; and numeral 28 
a drive signal interrupting circuit, acting as output torque cutting 
means, connected between the motor controller 23 and the inverter circuit 
24. In this case, the PWM signal generated by the motor controller 23 is 
output to the inverter circuit 24 so that it may be changed into a 
sinusoidal wave motor current. When a first output torque out command 
signal a.sub.1 is output from the CPU 22 and if a second output torque cut 
command signal a.sub.2 is output from the shift switch 21, the drive 
signal interrupting circuit 28, if connected between the controller 23 and 
the inverter circuit 24, interrupts the output of the PWM signal. Then, 
the first output torque cut command signal a.sub.1 is output directly to 
the drive signal interrupting circuit 28, not through the motor controller 
23. As a result, the motor 25 can be stopped without fail by the first 
output torque cut command signal a.sub.1 even if the motor controller 23 
malfunctions. On the other hand, the second output torque cut command 
signal a.sub.2 is output directly to the drive signal interrupting circuit 
28, not through the CPU 22 and the motor controller 23. As a result, even 
if the CPU 22 malfunctions, the motor 25 can be stopped without fail by 
the second output torque cut command signal a.sub.2. 
In the foregoing embodiments, if the second output torque cut command 
signal a.sub.1 of the shift switch 21 were to be instantly input to the 
drive signal interrupting circuit 28 to cut the output torque, the output 
torque would abruptly stop producing shock. Between the shift switch 21 
and the drive signal interrupting circuit 28, therefore, there is 
connected signal delay circuit 35 for delaying the second output torque 
cut command signal a.sub.2 by a delay time t to produce and input a third 
output torque cut command signal a.sub.3 to the drive signal interrupting 
circuit 28. 
In the foregoing embodiments, the vehicle speed and the accelerator opening 
are detected and used to calculate the output torque command. An output 
torque command for an accelerator opening of 100% is calculated with 
reference to an output torque command map and by multiplying the value for 
the accelerator opening of 100% by a torque output factor which is 
determined by referring to a torque output factor map. 
The output torque command map and the torque output factor map are prepared 
by taking into consideration the power performance and the electric energy 
consumption efficiency of the electromobile, but the electric energy 
consumption efficiency cannot be increased with the power performance also 
being increased. Thus, both the power performance and the electric energy 
consumption efficiency are set to compromise points so that the 
electromobile cannot be driven completely according to the driver's taste. 
Therefore, in the electromobile of the present invention the output torque 
command map and the torque output factor map can be switched to suit the 
driver's taste. 
In FIG. 16 reference numeral 11 designates an output control unit composed 
of a CPU, RAM, ROM and the like, although not shown; numeral 12 represents 
vehicle speed detecting means such as a r.p.m. sensor for detecting the 
speed of the electromobile, for example, in terms of the r.p.m. of the 
output shaft of the motor 25. Numeral 13 is an accelerator opening 
detecting means such as a acceleration sensor for detecting the 
accelerator opening in terms of the depression of an accelerator pedal 
(not shown). Numeral 21 designates a shift switch for detecting the range, 
which is selected by the driver's manipulation of a shift lever, i.e. 
shift lever position or range position. Numeral 18 designates power 
performance switching means for detecting the switching of the power 
performance such as a power mode or an economy mode, which is effected by 
the manipulation of a power/economy mode switch (not shown). 
Numeral 12a designates vehicle speed calculating means for calculating the 
vehicle speed from the r.p.m. signal of the vehicle speed detecting means 
12; numeral 13a accelerator opening calculating means for calculating the 
accelerator opening from the signal representative of the accelerator 
pedal depression of the accelerator opening detecting means 13; numeral 
21a range deciding means for deciding a selected range from the signal of 
the range position of the shift switch 21; and numeral 18a power 
performance switching deciding means for deciding the switching of the 
power performance from the switching signal of the power performance 
switching means 18. 
Numeral 15 designates output torque command calculating means for 
calculating the output torque command in response to the signal for the 
vehicle speed calculated by the vehicle speed calculating means 12a, the 
signal for the accelerator opening calculated by the accelerator opening 
calculating means 13a, the signal for range decided by the range deciding 
means 21a and the signal for the power performance decided by the power 
performance switching deciding means 18a. Numeral 16 designates an output 
torque map which is referred to when the output torque command calculating 
means 15 calculates the output torque command. Each map is composed of at 
least two power performance plots corresponding to the individual power 
performances. In this case, each of the output torque command map of FIG. 
17 and the torque output factor map of FIG. 18 has both a power mode plot 
and an economy mode plot. In FIGS. 17 and 18, solid curves indicate the 
power mode plots, and broken curves indicate the economy mode plots. 
Numeral 17 designates output torque command output means for outputting the 
output torque command, which is calculated by the output torque command 
calculating means 1, to the motor 25. In response to the output torque 
command from the output torque command output means 17, the motor 25 is 
driven to generate an output torque corresponding to the motor current. 
In an electromobile thus constructed, when the driver depresses the 
accelerator pedal while holding the shift lever in the forward range 
(i.e., D-range), for example, the output torque command calculating means 
15 receives the signal for vehicle speed calculated by the vehicle speed 
calculating means 12a and the signal for accelerator opening calculated by 
the accelerator opening calculating means 13a, to calculate the output 
torque command with reference to the output torque map 16, i.e., the 
output torque command map of FIG. 17 and the torque output factor map of 
FIG. 18. 
If the driver then switches to the power mode, the economy mode or the like 
by operation of the power/economy mode switch or the like, the power 
performance switching means 18 detects that switching to produce a 
switching signal, which is received by the power performance switching 
deciding means 18a to decide the power performance. 
In response to the power performance signal of the power performance 
switching deciding means 18a, the output torque command calculating means 
15 selects one of the plots in the output torque map 16 and calculates the 
output torque command with reference to the selected plot. 
In accordance with the vehicle speed signal of the vehicle speed 
calculating means 12a, more specifically, the output torque command 
calculating means 15 refers to one of the power performance plots (e.g., 
the power mode plot or the economy mode plot) in the output torque command 
map of FIG. 17 and calculates the maximum output torque command for the 
accelerator opening of 100[%]. Next, the accelerator opening calculating 
means 13a calculates the accelerator opening from the signal 
representative of the accelerator pedal depression. 
Subsequently, the output torque command calculating means 15 refers to one 
of the power performance plots (e.g., the power mode plot or the economy 
mode plot) in the torque output factor map of FIG. 18 in accordance with 
the accelerator opening signal and calculates the torque output factor for 
the accelerator opening at that instant and the output torque command at 
this instant is calculated by multiplying the maximum output torque 
command by the torque output factor. 
The power/economy mode switch is used here as the power performance 
switching means 18. If this power performance switching means 18 is a 
variable resistor, the values of the maximum output torque command set 
according to the output torque command map and the torque output factor 
set according to the torque output factor map can be continuously changed 
to provide a drive more desirable to the driver. 
On the other hand, the maps can be automatically switched according to the 
speed of depression of the accelerator pedal. In this case, the economy 
mode of the electromobile can be automatically switched to the power mode 
even during running if the accelerator pedal is abruptly depressed. 
Incidentally, in the electromobile using no transmission, the regenerative 
braking forces for the equal depressions of the accelerator pedal are 
equal. This makes it impossible to set a braking torque, in contrast to 
engine braking in a gasoline-powered automobile. Moreover, if the 
regenerative braking force for each range position is fixed, a high load 
is applied to the battery 26 (as shown in FIG. 11) in high-speed running, 
i.e., at a high voltage so that the battery power is more quickly 
depleted. 
Therefore, output torque command maps are prepared for the forward range, 
the low (L) range and reverse (R) range so that different braking torques 
may be set in the output torque command maps for the forward range and the 
low range. 
These braking torques can be changed according to the vehicle speed so that 
no high load is applied to the battery during the high-speed running, 
thereby improving the range (distance of travel ) allowed by the battery 
before recharging is required. 
In FIGS. 20 and 21, the output torque command map for the forward range and 
the low range, respectively, have first quadrants indicating the state in 
which the motor 25 (as shown in FIG. 1) is driven in forward running, 
second quadrants indicating backing in the forward range, e.g. slipping 
downhill backward with the vehicle in forward, third quadrants indicating 
reverse running, and fourth quadrants indicating regenerative braking in 
forward running. As a result, the braking torque is determined by the 
minimum T.sub.min of the output torque command of the third quadrant. 
In FIG. 22, on the other hand, the output torque command map for the 
reverse range has its first quadrant indicating the state in which the 
motor (of FIG. 1) is driven in reverse running, its second quadrant 
indicating the accelerating state at the start, its third quadrant 
indicating forward running, and its fourth quadrant indicating 
regenerative braking in reverse running. As a result, the braking torque 
is determined by the minimum T.sub.min of the output torque command of the 
third quadrant. Incidentally, this output torque command map for the 
reverse range provides that the output torque command is set to 0 when the 
vehicle speed reaches 30 [Km/h] in the first quadrant. Thus, safety is 
retained by avoiding excessive speed in reverse running. 
Step S31: 
The routine is initialized. 
Step S32: 
It is decided whether or not the ignition is OFF. The routine advances to 
Step S33, if the ignition is OFF, but to Step S34 if ON. 
Step S33: 
The routine is terminated. 
Step S34: 
The accelerator opening is calculated from the signal for depression of the 
accelerator pedal by the accelerator opening calculating means 13a (as 
shown in FIG. 16). 
Step S35: 
The vehicle speed is calculated from the r.p.m. signal by the vehicle speed 
calculating means 12a. 
Step S36: 
The selected range is decided from the signal of the range position by the 
range deciding means 21a. 
Step S37: 
It is decided whether or not the range decided by the range deciding means 
21a is the neutral range. The routine advances to Step S38, if the answer 
is YES, but to Step S39 if NO. 
Step S38: 
The maximum T.sub.max and the minimum T.sub.min of the output torque 
command are set to 0. 
Step S39: 
It is decided whether or not the range decided by the range deciding means 
21a is forward. The routine advances to Step S40, if the answer is YES, 
but to Step S41 if 
Step S40: 
The maximum T.sub.max and the minimum T.sub.min of the output torque 
command are read with reference to the output torque command map for the 
forward range of FIG. 20. 
Step S41: 
It is decided whether or not the range decided by the range deciding means 
21a is the low range. The routine advances to Step S42, if the answer is 
YES, but to Step S43 if NO. 
Step S42: 
The maximum T.sub.max and the minimum T.sub.min of the output torque 
command are read with reference to the output torque command map for the 
low range of FIG. 21. 
Step S43: 
It is decided whether or not the range decided by the range deciding means 
21a is the reverse range. The routine advances to 
Step S44, if the answer is YES, but to 
Step S45 if NO. 
Step S44: 
The maximum T.sub.max and the minimum T.sub.min of the output torque 
command are read with reference to the output torque command map for the 
reverse range of FIG. 22. 
Step S45: 
The maximum T.sub.max and the minimum T.sub.min of the output torque 
command are set to 0 if the range decided by the range deciding means 21a 
does not belong to any range (R, D, L and N), for example, in the case 
where the decided range is parking (P) and in the case of a malfunction of 
the range deciding means 21a. 
Step S46: 
The output torque command of each range is calculated by the output torque 
command calculating means 15. The output torque commands is expressed, if 
designated as T, as follows: 
EQU T=C(T.sub.max -T.sub.min)-T.sub.min 
wherein C: Accelerator Opening. 
Step S47: 
The output torque command T is output to the motor 25 by the output torque 
command output means 17, and the routine is returned to Step S32. 
The present invention should not be limited to the foregoing embodiments 
but can be modified in various manners without departing from the gist 
thereof, and these modifications should not be excluded from the scope of 
the present invention.