Comparative study of adjustable-speed drives for heat pumps. Final report

Technical Report · Fri Aug 01 04:00:00 EDT 1986

OSTI ID:5477542

Mohan, N; Ramsey, J W

This study evaluates the feasibility of modulating heat pump capaciy by compressor-motor speed variation. Six adjustable speed ac motor drive methods are addressed for unitary reciprocating and rotary compressors for residential and light commercial applications. The six techniques include: square wave, voltage source inverters (VSI); square wave, current source inverters (CSI); pulse-width-modulated, voltage source inverters (PWM); electronically-commutated synchronous motors with a permanent magnet field (ECM); high-frequency, high speed motors using low-loss magnetic materials (HFM) and; pole-amplitude-modulation in induction motors (PAM). These techniques are compared with sinle-speed (single-phase, permanent phase-split-capacitor motors and three-phase motors) and two-speed compressor motors. The VSI and the PWM inverter-driven induction motor drives appear to be attractive for continuous speed adjustments in a six-to-one range. Each of these inverters were built in the laboratory and their performance characteristics are obtained in terms of the harmonics injected into the utility grid and the power factor of operation. Based on a bin-type energy analysis, continuously adjustable-speed heat pumps show a reasonable payback period in cooling dominated locations with relatively high electric costs, such as Dallas and Phoenix.

• Research Organization: Minnesota Univ., Minneapolis (USA)
• OSTI ID: 5477542
• Report Number(s): EPRI-EM-4704; ON: TI86920442
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
320100* -- Energy Conservation
Consumption
& Utilization-- Buildings
AIR CONDITIONING
COMPARATIVE EVALUATIONS
ELECTRIC MOTORS
ELECTRICAL EQUIPMENT
EQUIPMENT
HEAT PUMPS
HEATING
INVERTERS
MOTORS
SPACE HEATING