Resolver | Drives

Summit drive implements a flexible strategy for reading resolvers that supports multiple transformation ratios without the modification of the electronics.

A basic set of parameters allows to adapt the signal generation to most the resolvers options

Name	Key / address	NVM	Access	Data type	Data range	Units
Resolver pair poles	0x368	yes	Read-write	UINT16	full data type range	pair poles
Resolver max. speed	0x369	yes	Read-write	FLOAT32	from 0 to max. resolver speed	Hz
Resolver excitation amplitude	0x36A	yes	Read-write	UINT32	0 to 100000	% * 1000
Resolver Polarity	0x36E	yes	Read-write	UINT16	Standard or reversed	-
See this link for accessing to this register through CANopen and EtherCAT

These parameters are the minimum information need by the driver to obtain valid resolver readings:

Pair poles. Indicates the number of pair poles of the resolver.

If the resolver is composed of one pair pole, then it can be used as reference feedback, and forced alignment methods are not required. See Commutation section for further information.
Maximum speed. Indicates the maximum reachable speed of the resolver rotation in rev/s.

This parameter must be set as near as possible to the real maximum speed of the system. The smaller it is, the smother will be the resolver readings.
Excitation amplitude. Indicates the % of maximum voltage (product dependent) to be applied to the excitation signal sent to the resolver. Modifying this parameter different transformation ratios are supported.

Excitation frequency is fixed to 10 kHz
Polarity. Allows to configure the positive and negative direction of the resolver readings. 0 value applies standard polarity (read directly from the feedback) and a value different than 0 reverses the polarity

In case that the resolver doesn't work properly with the parameter mentioned above, a deeper configuration might be done. Summit products implement an observer to keep tracking a proper read of the resolver signals. The parameters above belongs to this observer and might be modified if the resolver readings are too noisy or the dynamic response is not the expected one.

Name	Key / address	NVM	Access	Data type	Data range	Units
Resolver error filter corner	0x36B	yes	Read-write	FLOAT32	From 0 to Max. resolver speed	Hz
Resolver PI zero frequency	0x36C	yes	Read-write	FLOAT32	full data type range	Hz
Resolver PI proportional	0x36D	yes	Read-write	FLOAT32	full data type range	-
See this link for accessing to this register through CANopen and EtherCAT

Deeper details about how this observer works is available on this white paper.

In order to validate the resolver configuration, there are parameters for monitoring purpose

Name	Key / address	NVM	Access	Data type	Data range	Units
Resolver angle	0x044	no	Read	FLOAT32	0.0 to 1.0	degrees / 360
Resolver velocity	0x045	no	Read	FLOAT32	- max. resolver speed to max. resolver speed	Hz
Resolver status	0x046	no	Read	UINT16	See below	-
Resolver sine	0x047	no	Read	FLOAT32	-1.0 to 1.0	1.0 / Measuring range
Resolver cosine	0x048	no	Read	FLOAT32	-1.0 to 1.0	1.0 / Measuring range
See this link for accessing to this register through CANopen and EtherCAT

Angle. Contains the angle measured from the resolver.
Velocity. Measure the speed of the resolver in rev / s. Resolver pair poles are taking into account for the velocity measurement, so the result is mechanical speed.
Status. It is a boolean mask that indicates the status of the resolver readings:

Bit 15 .. 3	Bit 2	Bit 1	Bit 0
Reserved	Loss of Tracking (LOT)	Loss Of Signal (LOS)	Degradation Of Signal (DOS)

Sine and cosine. Contains the value of the Sin and Cos signals from the resolver.