Claims:I/We claim:

1. A series regulator and rectifier unit (200) in an automotive generator comprising:
a rectification and Positive half cycle regulator Silicon Controlled Rectifier (220);
a negative half cycle lamp regulator Silicon Controlled Rectifier (204);
a lamp control circuit (215) that controls the Negative cycle Silicon Controlled Rectifier (204);
a series regulator and rectifier unit control circuit (200) that controls a Positive cycle Silicon Controlled Rectifier for charging a battery;
the battery (112);
a set of DC loads (125); and
characterized in that,
a split ground terminal (210) that selectively switches the lamp control circuit (215) and the battery charging rectifier control circuit (220) between a commonly grounded configuration and separately grounded configuration.

2. The series regulator and rectifier unit (200) as claimed in claim 1, wherein a means of an implementation of the split ground terminal (210) comprises a terminal block (300) for an electrical termination.

3. The series regulator and rectifier unit (200) as claimed in claim 1, wherein the lamp control circuit (215) and charge rectifier control circuit (220) are switched to a separate grounding configuration during an open ground testing using the means.

4. A split terminal (310) comprising two conducting terminals (312, 314), wherein said conducting terminals are separated by an insulator (316). , Description:TECHNICAL FIELD
[0001] The present subject matter relates, in general, alternator control unit in two-wheeled vehicles and more particularly a series regulator and rectifier unit in an automotive generator provided with a ground terminal that is used to connect the metal parts of a vehicle to a common potential, and the ground terminal is also used when testing a regulator.
BACKGROUND
[0002] Conventionally, in a series half-wave regulator cum rectifier, an input is connected to a three-phase low voltage AC generator which generates an AC voltage. The AC generator is of a configuration of a star connected winding on three phases, and a star point, as known to practitioners of art, is connected to a chassis of a vehicle to which the AC generator is fitted, forming a ground reference to a complete electrical system including a battery which is charged by the AC generator through a rectifier part of the series half-wave regulator cum rectifier. An AC side of the series half-wave regulator cum rectifier and an DC side share a same ground path in a control circuit. A problem that is unsolved is that during a ground open condition, current from an AC generator flows simultaneously into the DC side as well as common ground path, which in turn triggers an AC side SCR (Silicon Controlled Rectifier), leading to voltage regulation failure and fusing of a headlamp and other parts of electrical loads.
SUMMARY
[0003] The description in this disclosure provides a series regulator and rectifier unit in an automotive generator. The series regulator and rectifier unit including a rectification and Positive half cycle regulator Silicon Controlled Rectifier, a negative half cycle lamp regulator Silicon Controlled Rectifier, a lamp control circuit, a battery, a set of DC loads and a split ground terminal.
[0004] The lamp control circuit controls the Negative cycle Silicon Controlled Rectifier. The series regulator and rectifier unit control circuit controls a Positive cycle Silicon Controlled Rectifier for charging a battery. The split ground terminal that selectively switches the lamp control circuit and the battery charging rectifier control circuit between a commonly grounded configuration and separately grounded configuration.
[0005] In some embodiments, a means of an implementation of the split ground terminal comprises a terminal block for an electrical termination.
[0006] In some embodiments, the lamp control circuit and charge rectifier control circuit are switched to a separate grounding configuration during an open ground testing using the means.
[0007] In another aspect, a split terminal including two conducting terminals. The conducting terminals are separated by an insulator.
[0008] A configuration where the above problem is overcome by having a separate ground path for both AC and DC side using a split type terminal design. The present subject matter provides a technique to have a separate ground path for both AC and DC side using split type ground terminal design. Since the headlamp side SCR is using a separate ground path, there is no possibility of current flow during ground open. Hence lamp side SCR remaining at OFF condition will not affect the system parts during ground open. This description shows an implementation of the system with a single-phase AC generator. The principles and implementation schemes in this description are valid for three-phase alternators use also.

BRIEF DESCRIPTION OF DRAWINGS
[0009] The features, aspects, and advantages of the present subject matter will be better understood with regard to the following description and accompanying figures. The use of the same reference number in different figures indicates similar or identical features and components.
[0010] Fig.1 illustrates a prior art schematic diagram of a conventional series half-wave regulator using two SCR in accordance with an embodiment of the present subject matter;
[0011] Fig.2 illustrates a schematic diagram of a series regulator in accordance with an embodiment of the present subject matter;
[0012] Fig. 3 illustrates an electrical terminal assembly box of the series regulator of FIG. 2 in accordance with an embodiment of the present subject matter; and
[0013] Fig. 4A and Fig. 4B illustrate an implementation of a split terminal to solve ground open condition issues in accordance with an embodiment of the present subject matter.

DETAILED DESCRIPTION
[0014] The present subject matter provides a technique of utilizing both AC and DC side control circuit without affecting other system parts during the ground open condition.
[0015] Fig.1 illustrates a prior art schematic diagram of a conventional series half-wave regulator using two SCR in accordance with an embodiment of the present subject matter. The conventional series half-wave regulator and the electrical system, including the battery that is charged as 100. The Regulation and Rectifier unit 110 contains, in principle, the electrical and electronic components to handle power to a various electrical system parts of a vehicle and also charge the battery 112. The Regulation and Rectifier unit 110 receives input from a single-phase AC generator 101 which generates an AC voltage. The AC voltage thus generated includes a positive half and a negative half-cycle, and one end of the AC generator 101 winding is connected to the metal parts of the vehicle, including the chassis as the point of grounding. The construction of the Regulation and Rectification unit 110 is such that the positive half cycle of the single-phase voltage provides power to charge the battery, and the negative half cycle provides power to the headlamp 103 through the appropriate triggering of the first SCR 104 by the control circuit 105 powering the lamp.
[0016] The second SCR 106 is for full-wave rectification of the AC generator for battery charging. In both these half cycle control systems, the reference ground is the ground point 107.
[0017] The DC loads 115 of the vehicle are powered by the battery 112, and so the load voltage is never more than the voltage of the battery 112. The battery ground point is the chassis 122 at any point near the battery in the vehicle, and the DC loads 115 are grounded to the chassis near to each of them physically in the vehicle. FI (Fuel injection system) is also) powered by the generator output.
[0018] The disadvantage in the conventional series half-wave regulator is that the common ground path is shared between AC and DC side control circuit, which further affects the system parts during an open ground condition, represented as 107 and 130. During the ground open condition, ACG (AC Generator) current flowing through DC side control circuit and common ground path potentially cause triggering of the AC side SCRs leading to loss of voltage regulation resulting in a high voltage causing failure of one or more parts of the electrical system including the fusing of the headlamp.
[0019] The ground terminal 107 is the power ground reference to the Regulator and Rectifier unit 110. Since this ground terminal 107 is also connected to the battery ground terminal through the common ground point 130, the common potential of these three points ensures that the regulator and the battery see the same ground reference potential as the AC load lamp and the AC generator.
[0020] The ground reference 130 for the SCR 104 switching the headlamp is independent of the ground reference to SCR 104 control circuit for negative half cycle rectification and the control circuit of the Regulator and Rectification unit 110 through the SCR 135. Further, the ground points 107 and 130 are also independent.
[0021] While the ground terminals of the battery and the DC loads, as well as the Fuel Injection units, are distributed in the vehicle, the chassis being common and metallic in nature, provides a common reference to all these ground points. The ground point for the Regulation and Rectification Unit 107 is at a distinctly separate location, and disconnection of this ground 107 leads to an anomalous situation where the battery regulatory effect is lost when the link between the chassis ground point 130 and 107 is lost. The regulatory SCR 135 and its control circuit 140 have a common ground termination being internally connected to the lamp control SCR’s 104 control unit 105 in the Regulator and Rectifier unit, and this combined ground is brought out as a ground terminal 107 which is a disadvantage when testing the Regulation and Rectifier unit prior to fitting it into an automotive vehicle.
[0022] Fig. 2 illustrates a schematic diagram of a series regulator in accordance with an embodiment of the present subject matter. The disadvantage of during testing and allowing spurious signals into the system during testing disclosed in FIG. 1 is overcome by having a separate ground path for both AC and DC side by having separate ground terminal using split type terminal design. Essentially internal connections of the regulatory SCR 135 in the Regulation and Rectification unit and its control circuit 140 as shown in the FIG-1 having the common ground termination which is internally connected to the ground terminal of the rectifier SCR 106 and the control unit 105 of the rectifier SCR 106 in the Regulator and Rectifier unit and brought out as a ground terminal 107 is separated into a split terminal 210. In some embodiments, the series regulator implementation of FIG. 2 separates the ground terminal 107 from a split arrangement 107.
[0023] FIG. 3 shows an electrical terminal assembly box 300 the series regulator of FIG. 2 in accordance with an embodiment of the present subject matter., In some embodiments, the electrical terminal assembly box 300, known in the art, with the split terminal and how a split terminal (310) is split mechanically by splitting the single terminal into two to be used for both the lamp and battery side ground separately. In such a case, there is no need for any electronic circuit internally in the Regulator Rectifier unit to avoid failure during a ground open condition. The split terminal 310 contains two parts 312 and 314, with each part of the split terminal 310 insulated from the other for electrical insulation using a suitable insulator part 316. The grounding connection wires in a typical use scenario terminates at the end of a split terminal 320 with a clip containing crimped wires.
[0024] The spurious triggering of the lamp side SCR 104 through a common ground path is now avoided, with the ground terminal being separated by using a split type terminal design 210. In some embodiments, as both positive and negative control circuit may share a separate ground path for their operation.
[0025] Fig. 4A and Fig. 4B illustrate an implementation of a split terminal to solve ground open condition issues in accordance with an embodiment of the present subject matter. In some embodiments, a circulating current path 410 as shown in FIG. 4A is implemented without the split terminal 210. The two control circuits 420 controlling a Silicon controlled rectifier (SCR) lamp control rectifier 405 controlling a Regulator Rectifier unit silicon-controlled rectifier (SCR) respectively are internally connected in the R/R unit. During a Ground open test, the R/R unit is tested without a ground connection, and the requirement is no output or malfunction is acceptable throughout the operating speed. In some embodiments, to avoid the malfunction, as described in this illustration, using the split terminal design by reducing chances of the electronic circuit to operate the R/R unit under the open ground condition. During the open ground test without a split terminal, a circulating current 410 potentially flows through a negative side control circuit, causing and is a sum of a capacitor current 403 and a control circuit current 430. The capacitor current 403 and the control circuit current 430 potentially trigger a gate of the negative or lamp side control circuit Silicon Controlled Rectifier since the Silicon controlled rectifier circuit has lost its ground connection that was established by a ground connection 440. In some embodiments, as shown in Fig. 4A, both the lamp and circuit driving the currents labelled 403 and 405 that share the same common ground path. During the open ground condition, a false trigger can occur on the lamp silicon control rectifier circuit 420.
[0026] During the ground open test, the current flow is arrested to the negative side control circuit and flows only through the positive side control circuit by using the split type terminal design. The split terminal 210 ensures that the R/R ground and the Lamp silicon controlled rectifier control systems 215 and 220 respectively are independently grounded.