Vehicle or environment-controlled unit having a multiphase alternator with a protected high-voltage bus

Patent metadata

Field	Value
Publication number	US-9431820-B2
Application number	US-201514922841-A
Country	US
Kind code	B2
Filing date	Oct 26, 2015
Priority date	Mar 30, 2012
Publication date	Aug 30, 2016
Grant date	Aug 30, 2016

Abstract

A mobile environment-controlled unit, such as an over-the-road compartment trailer, having an environmental-control system, such as a refrigeration unit, powered by an alternator and having a high-voltage alternating current (AC) bus. The unit incorporates a high resistance ground scheme and can incorporate a solid-state input module to detect phase-chassis faults. This combination provides an improvement in protection for mobile applications that cannot have a voltage reference (or neutral point) solidly connected to earth ground.

First claim

What is claimed is:

1. A mobile environment-controlled unit comprising:
a chassis;
a compartment supported by the chassis; and
an environmental-control system supported by the chassis and in environmental communication with the compartment, the environmental-control system being configured to control an environmental parameter of the compartment, the environmental-control system including
a multiphase alternator powered by an internal combustion engine and to supply electrical power for the environmental-control system, the alternator having phase windings and a neutral point for the phase windings; and
a high-resistance resistor electrically coupling the neutral point for the phase windings to the chassis.

2. The mobile environment-controlled unit of claim 1 , wherein the environmental-control system further includes
a solid-state module electrically coupling the neutral point for the phase windings to the chassis, the module being configured to monitor a voltage from the neutral point to the system chassis, and to provide an output when the monitored voltage indicates a possible phase-to-structure fault.

3. The mobile environment-controlled unit of claim 1 , wherein the environmental-control system further includes
a controller configured to control the environmental-control system for affecting the environment of the compartment.

4. The mobile environment-controlled unit of claim 1 , wherein the high-resistance resistor has a value in a range sufficient to limit current in a possible phase-to-chassis fault and to dissipate parasitic current during a possible intermittent phase-to-chassis fault.

5. The mobile environment-controlled unit of claim 1 , wherein the high-resistance resistor has a value between 1 kΩ and 1 MΩ.

6. The mobile environment-controlled unit of claim 1 , wherein the high-resistance resistor has a value between 10 kΩ and 100 kΩ.

7. The mobile environment-controlled unit of claim 1 , wherein the high-resistance resistor has a value between 30 kΩ and 70 kΩ.

8. The mobile environment-controlled unit of claim 1 , wherein the alternator is a three-phase alternator with the phase windings configured in a wye arrangement, and wherein the neutral point is the center of the wye arrangement.

9. A vehicle comprising:
a chassis;
a multiphase alternator powered by an internal combustion engine and to supply electrical power for the environmental-control system, the alternator having phase windings and a neutral point for the phase windings; and
a high-resistance resistor electrically coupling the neutral point for the phase windings to the chassis.

10. The vehicle of claim 9 , and further comprising:
a solid-state module electrically coupling the neutral point for the phase windings to the chassis, the module being configured to monitor a voltage related to the neutral point for the phase windings and the system chassis, and to provide an output when the monitored voltage indicates a possible phase-to-structure fault.

11. The vehicle of claim 9 , and further comprising:
a controller configured to control the environmental-control system for affecting the environment of the compartment.

12. The vehicle of claim 9 , wherein the high-resistance resistor has a value in a range sufficient to limit current in a possible phase-to-chassis fault and to dissipate parasitic current during a possible intermittent phase-to-chassis fault.

13. The vehicle of claim 9 , wherein the range of the high-resistance resistor is between 30 kΩ and 70 kΩ.

14. The vehicle of claim 9 , wherein the alternator is a three-phase alternator with the phase windings configured in a wye arrangement, and wherein the neutral point is the center of the wye arrangement.

15. A mobile environment-controlled unit comprising:
a chassis;
a compartment supported by the chassis;
an environmental-control system supported by the chassis and in environmental communication with the compartment, the environmental-control system being configured to control an environmental parameter of the compartment, the environmental-control system including
an internal combustion engine;
a three-phase alternator to be powered by the internal combustion engine and to supply electrical power to the environmental-control system, the alternator having phase windings in a wye arrangement and a neutral point for the phase windings;
a high-resistance resistor electrically coupling the neutral point for the phase windings to the chassis, the high-resistance resistor having a value in a range sufficient to limit current in a possible phase-to-chassis fault and to dissipate parasitic current during a possible intermittent phase-to-chassis fault;
a solid-state module electrically coupling the neutral point for the phase windings to the chassis, the module being configured to monitor a voltage from the neutral point for the phase windings to the system chassis, and to provide an output when the monitored voltage indicates a possible phase-to-structure fault.

16. The mobile environment-controlled unit of claim 15 , wherein the environmental-control system further includes
a controller configured to control the environmental-control system for affecting the environment of the compartment, to receive the output from the solid-state module, and to control the environment-control system based on the output.

17. The mobile environment-controlled unit of claim 15 , wherein the range of the high-resistance resistor is between 30 kΩ and 70 kΩ.

Assignees

• Thermo King Corp

Inventors

• Neddermeyer Iii Robert N
• Truckenbrod Gregory R
• Nelson Matthew S
• Muralidhar Ashok
• Henze Christopher P

Classifications

• B60H1/3232

  particularly adapted for load transporting vehicles (B60H1/3226 takes precedence) · CPC title

• H02H9/08

  Limitation or suppression of earth fault currents, e.g. Petersen coil · CPC title

• B60P3/20 Primary

  Refrigerated goods vehicles (air treatment of goods space B60H; {air-conditioning means for freight cars, isothermic wagons B61D27/0027; superstructures for refrigerated goods vehicles B62D33/048}) · CPC title

• H02H9/02 Primary

  responsive to excess current {(current limitation for voltage regulators G05F1/573; disconnection after limiting H02H3/025)} · CPC title

• B60H1/00978

  Control systems or circuits characterised by failure of detection or safety means; Diagnostic methods · CPC title