FIELD OF THE INVENTION
The present invention relates to Lamp Control device to improve efficiency of power utilization in two / three Wheelers and in General purpose Engines.
BACKGROUND OF THE INVENTION AND PRIOR ART
Permanent Magnet Generators ( also called Magneto or AC Generator ) are widely used in Two / Three Wheelers and in General purpose Engines for generation of electricity for powering constant loads (Head Lamp, Tail Lamp, Meter Lamp, etc) & Intermittent loads ( Brake Lamp, Horn, Indicator etc usually connected across a Battery) & other constant loads used for Ignition or other purposes.
The generator is used with the associated Regulator, as in most applications the speed of the engine vary with in a specified range and since the generator produces higher output at higher speeds, the regulator is used to control the output. There are two possible types of regulator depending on how the load is connected to the generator as described below.
A) Series type regulator - Here the control element ( usually a Silicon Controlled Rectifier (SCR), Metal Oxide Semiconductor Field Effect Transistor (MOSFET) ) is connected in series with the load. The current drawn from the source is equal to the current drawn by the load. Hence the Power (Current * Voltage) is drawn form the source to the extent of the load.
B) Shunt type regulator - Here the control element ( usually a Silicon Controlled Rectifier (SCR), Metal Oxide Semiconductor Field Effect Transistor (MOSFET) ) is connected in parallel to the load. The current drawn from the source irrespective of whether the load draws current or not. Hence the Power is always drawn from the source whether it is utilized by the load or not. This makes shunt type of connection is less efficient compared to series type connection.
Even though many configurations are possible which can be classified based on the connections made between the Generator and the Regulator, the performance

characteristic, efficiency & the cost of the system, for the purpose of explaining the current invention, following three configurations are considered.
Configuration A. - DC System - Series regulation.
Here, the output from the generator is rectified and used for charging the battery through a series regulator. All the loads (constant & intermittent lamp loads & other DC loads) are connected across the battery.
Configuration B. - AC/DC System. - AC - Shunt regulation, DC - Series Regulation Here, there are two outputs from the generator which are connected to the regulator. A series DC regulator is used for battery charging for catering to intermittent loads & other constant DC loads & a AC shunt type regulator is used for constant lamp loads.
Configuration C. - AC/DC System. - AC - Series regulation, DC - Series Regulation Here, the output from the generator is connected to the regulator. A series DC regulator is used for battery charging for catering to intermittent loads & other DC loads and a AC series type regulator is used for constant lamp loads.
Wherein the type A configuration has better efficiency and cost of the generator is high, hence compromise in cost is required.
Type B configuration low efficiency and cost of the generator also low, hence compromise in efficiency is not avoidable.
Type C configuration has better efficiency and cost of the generator is high for alternative 1 where as cost of the generator is low for alternative 2. Hence compromise in cost for alternative 1 and compromise in performance is desired for alternative 2.
Thus, present invention provides better efficient device with generator cost less than A and C (Alternative 1) without compromising in cost, performance and efficiency.


OBJECTS OF THE INVENTION
The primary object of the present invention is to provide lamp control device to improve efficiency of power utilization.
Yet another object of the present invention is to provide a controlling apparatus to control power utilization of constant load lamp through pulse width modulation (PWM).
Still another object of the present invention is to provide a methodology perform the above said objects efficiently.
Still another object of the present invention is to provide efficient device with generator cost less than aforesaid configurations A and C (Alternative 1) without compromising in cost, performance and efficiency.
STATEMENT OF THE INVENTION
The present invention relates to a controlling apparatus to control constant load lamp through pulse width modulation (PWM), said apparatus comprising signal conditioning circuit to generate status of generator speed; and a microcontroller to generate PWM based on the status of battery and speed of the generator; a device to control load lamp for efficient power utilization, said device comprising a control unit regulated by a PWM signal to connect constant load lamp with a battery and also a method to control load lamp for efficient power utilization by sensing battery to determine PWM duty and cycle-

time by existing means; obtaining RPM on the basis of determined duty and time; comparing RPM of step (b) with the pre-determined minimal requisite RPM; and starting the PWM to make corresponding changes in the duty, if RPM of step (b) is less than the requisite RPM to provide efficient power utilization.
BREIF DESCRIPTION OF ACCOMPANAYING DRAWINGS
Figure 1 shows configuration Type A, B, C and D connection diagram along with
performance of each configuration.
Figure 2 shows controller circuit for present invention.
Figure 3 shows flow chart to implement control logic.
Figure 4 shows implementation through the controller used for ignition purpose.
DETAILED DESCRIPTION OF THE INVENTION
The primary embodiment of the present invention is a controlling apparatus to control constant load lamp through pulse width modulation (PWM), said apparatus comprising signal conditioning circuit to generate status of generator speed; and a microcontroller to generate PWM based on the status of battery and speed of the generator.
In yet another embodiment of the present invention is output of the signal conditioning circuit is directly connected to the microcontroller.
In still another embodiment of the present invention is the apparatus is connected to the constant load lamp through switching device such as metal oxide semiconductor field effect transistor (MOSFET).
In still another embodiment of the present invention is status of the battery is either battery voltage or battery current.
In still another embodiment of the present invention is device to control load lamp for efficient power utilization, said device comprising a control unit regulated by a PWM signal to connect constant load lamp with a battery.

In still another embodiment of the present invention is control to the control unit is provided by considering the battery voltage and speed of the generator.
In still another embodiment of the present invention is the control unit consists of signal conditioning circuit to generate status of generator speed; and a microcontroller to generate PWM based on the status of battery voltage and speed of the generator.
In still another embodiment of the present invention is status of the battery is either battery voltage or battery current
In still another embodiment of the present invention is output of the signal conditioning circuit is directly connected to the microcontroller.
In still another embodiment of the present invention is a method to control load lamp for efficient power utilization, said method comprising steps of sensing battery to determine PWM duty and cycle-time by existing means; obtaining RPM on the basis of determined duty and time; comparing RPM of step (b) with the pre-determined minimal requisite RPM; and starting the PWM to make corresponding changes in the duty, if RPM of step (b) is less than the requisite RPM to provide efficient power utilization.
In still another embodiment of the present invention is the PWM is disabled and the lamp
load is enabled, if obtained RPM is more than the pre-determined minimal requisite
RPM.
In still another embodiment of the present invention is the determined duty cycle is set as
present duty cycle, if determined cycle is not equal to present cycle.
In still another embodiment of the present invention is the conventional microcontroller
which is used to ignition controller can be used along with control logic method
mentioned above as regulator.
Permanent Magnet Generators ( also called Magneto or AC Generator ) are widely used in Two / Three Wheelers and in General purpose Engines for generation of electricity for powering constant loads (Head Lamp, Tail Lamp, Meter Lamp, etc) & Intermittent loads

( Brake Lamp, Horn, Indicator etc usually connected across a Battery) & other constant loads used for Ignition or other purposes.
The generator is used with the associated Regulator, as in most applications the speed of the engine vary with in a specified range and since the generator produces higher output at higher speeds, the regulator is used to control the output. There are two possible types of regulator depending on how the load is connected to the generator as described below.
A) Series type regulator - Here the control element (usually a Silicon Controlled
Rectifier (SCR), Metal Oxide Semiconductor Field Effect Transistor (MOSFET)) is
connected in series with the load. The current drawn from the source is equal to the
current drawn by the load. Hence the Power (Current * Voltage) is drawn form the source
to the extent of the load.
B) Shunt type regulator - Here the control element (usually a Silicon Controlled Rectifier
(SCR), Metal Oxide Semiconductor Field Effect Transistor (MOSFET)) is connected in
parallel to the load. The current drawn from the source irrespective of whether the load
draws current or not. Hence the Power is always drawn from the source whether it is
utilized by the load or not. This makes shunt type of connection is less efficient compared
to series type connection.
Even though many configurations are possible which can be classified based on the connections made between the Generator and the Regulator, the performance characteristic, efficiency & the cost of the system, for the purpose of explaining the current invention, following three configurations are considered.
Configuration A. - DC System - Series regulation.
Here as shown in figure 1, the output from the generator is rectified and used for charging the battery through a series regulator. All the loads (constant & intermittent lamp loads & other DC loads) are connected across the battery.

Configuration B - AC/DC System - AC - Shunt regulation, DC - Series Regulation Here as shown in figure 1, there are two outputs from the generator which are connected to the regulator. A series DC regulator is used for battery charging for catering to intermittent loads & other constant DC loads & a AC shunt type regulator is used for constant lamp loads.
Configuration C - AC/DC System - AC - Series regulation, DC - Series Regulation Here as shown in figure 1, the output from the generator is connected to the regulator. A series DC regulator is used for battery charging for catering to intermittent loads & other DC loads and a AC series type regulator is used for constant lamp loads.
New Configuration D - DC System - Series regulation.
Here as shown in figure 1, the output from the generator is rectified and used for charging
the battery through a series regulator and the intermittent loads are connected across the
battery as in the conventional DC System - configuration A. But, the constant lamp loads
are connected to the battery through a new series regulator. The control to the regulator is
provided by considering the battery status (voltage or current) and the speed of the
Generator.
The characteristic in terms of Performance, Cost and Efficiency of the above systems are described below.
Configuration A:
The output throughout the speed range is constant for the constant & the intermittent
loads & other DC loads as it is supplied from the battery throughout the speed range.
Here the generator should be capable of catering to constant & intermittent loads & other DC loads from an optimum speed depending on the capacity of the battery. In practical applications, the cost of the generator goes up compared to configuration B. Being a series type regulation, the efficiency of the system is better than configuration B.

Configuration B:
The output to the constant lamp load is low until a particular speed which is decided based on application and the output to the intermittent loads & other DC loads are constant throughout the speed as it is supplied from the battery.
Here the generator output is optimized as the generator caters to the full requirement of the constant lamp loads only beyond a predetermined speed. Until this speed, the output is low.
Being a shunt type regulation for the constant lamp loads, the efficiency of the system is worse compared to configuration A.
Configuration C:
The output to the constant lamp load is low until an optimum speed and the output to the intermittent loads & other DC loads are constant throughout the speed as it is supplied from the battery. Since only half wave of AC is supplied to the constant lamp loads, the output requirement of the generator should be higher than the configuration B to give the same output as in configuration B. Hence the cost of the generator for giving an equal performance as configuration B is higher compared to the generator for the configuration B. Alternatively, if the output of the generator is same as in configuration B, then the performance output of constant lamp load will be lower than in configuration B.
Being a series type regulation for both the constant & intermittent loads, the efficiency of the system is better compared to configuration B.
New Configuration D:
The output to the intermittent loads & other DC loads are constant throughout the speed as it is supplied from the battery. The output to the constant lamp load is supplied through a series regulator which is controlled by a PWM (pulse width modulation) signal whose

duty cycle depends on the battery status (voltage or Current) and speed of the generator. The output voltage can be programmed to be same as the output in configuration B.
Being a series type regulation for both the constant & intermittent loads, the efficiency of the system is better compared to configuration B.
As the generator output is same as in configuration B, the cost of the generator is not increased nor there is a compromise in the efficiency or output performance as in configuration A and C respectively.
The configurations & characteristics of the systems are consolidated in Table 1 and in figure 1 also.

The new controller for the constant loads will be explained now. The controller circuit is as shown in Fig 2. It consists of a MOSFET driven by a control signal. The control signal is generated by implementing the control logic as per flow chart in Fig 2.
In practice, there is no requirement for a separate controller as in most vehicles microcontrollers are used for Ignition (for gasoline powered vehicles), display or other purposes which already have speed and battery as inputs. The control logic as described in Fig 3 can be implemented through one of these microcontrollers without need for a separate microcontroller for lamp control purpose.

The implementation through the controller used for ignition purpose is explained with the help of Fig 4 where in battery voltage & generator speed are considered for control. For the purpose of understanding, system as per configuration A is explained which shows a typical connection of electrical system employed in gasoline powered two/three wheeler. The AC Generator, the regulator, Battery are as per configuration A. The ignition controller is used to generate Ignition output through Ignition coil (not shown). The controller has speed input and battery input for its operation. The control logic as described in Fig 3 is implemented by using this microcontroller to generate the control signal for the constant lamp loads without need for a separate microcontroller exclusively for constant lamp loads control. This brings down the cost of implementation of the new controller for Constant load lamp control.
The new constant lamp load controller when implemented with the control logic improves the efficiency of the electrical system without need to sacrifice efficiency or increase in cost of generator.

We claim,
1. A controlling apparatus to control constant load lamp through pulse width
modulation (PWM), said apparatus comprising
a. signal conditioning circuit to generate status of generator speed; and
b. a microcontroller to generate PWM based on the status of battery and
speed of the generator.
2. The apparatus as claimed in claim 1, wherein the output of the signal conditioning circuit is directly connected to the microcontroller.
3. The apparatus as claimed in claim 1, wherein the apparatus is connected to the constant load lamp through switching device such as metal oxide semiconductor field effect transistor (MOSFET) or Transistor.
4. The apparatus as claimed in claim 1, wherein status of the battery is either battery voltage or battery current.
5. A device to control load lamp for efficient power utilization, said device comprising a control unit regulated by a PWM signal to connect constant load lamp with a battery.
6. The device as claimed in claim 5, wherein control to the control unit is provided by considering the status of battery and speed of the generator.
7. The device as claimed in claim 5, wherein the control unit consists of signal conditioning circuit to generate status of generator speed; and a microcontroller to generate PWM based on the status of battery and speed of the generator.

8. The device as claimed in claim 7, wherein status of the battery is either battery
voltage or battery current.
9. The device as claimed in claim 7, wherein output of the signal conditioning circuit
is directly connected to the microcontroller.
10. A method to control load lamp for efficient power utilization, said method
comprising steps of
a. sensing battery to determine PWM duty and cycle-time by existing means;
b. obtaining RPM on the basis of determined duty and time;
c. comparing RPM of step (b) with the pre-determined minimal requisite
RPM; and
d. starting the PWM to make corresponding changes in the duty, if RPM of
step (b) is less than the requisite RPM to provide efficient power
utilization.
11. The method as claimed in claim 10, wherein the PWM is disabled and the lamp
load is enabled, if obtained RPM is more than the pre-determined minimal
requisite RPM.
12. The method as claimed in claim 10, wherein the determined duty cycle is set as
present duty cycle, if determined cycle is not equal to present cycle.